zope.viewlet-3.7.2/ 0000755 0001750 0001750 00000000000 11376754277 014105 5 ustar tseaver tseaver zope.viewlet-3.7.2/buildout.cfg 0000644 0001750 0001750 00000000145 11376754171 016406 0 ustar tseaver tseaver [buildout]
develop = .
parts = test
[test]
recipe = zc.recipe.testrunner
eggs = zope.viewlet [test]
zope.viewlet-3.7.2/COPYRIGHT.txt 0000644 0001750 0001750 00000000040 11376754171 016201 0 ustar tseaver tseaver Zope Foundation and Contributors zope.viewlet-3.7.2/CHANGES.txt 0000644 0001750 0001750 00000003211 11376754171 015704 0 ustar tseaver tseaver =======
CHANGES
=======
3.7.2 (2010-05-25)
------------------
- Fixed unit tests broken under Python 2.4 by the switch to the standard
library ``doctest`` module.
3.7.1 (2010-04-30)
------------------
- Removed use of 'zope.testing.doctest' in favor of stdlib's 'doctest.
- Fixed dubious quoting in metadirectives.py. Closes
https://bugs.launchpad.net/zope2/+bug/143774.
3.7.0 (2009-12-22)
------------------
- Depend on zope.browserpage in favor of zope.app.pagetemplate.
3.6.1 (2009-08-29)
------------------
- Fixed unit tests in README.txt.
3.6.0 (2009-08-02)
------------------
- Optimize the the script tag for the JS viewlet. This makes YSlow happy.
- Remove ZCML slugs and old zpkg-related files.
- Drop all testing dependncies except ``zope.testing``.
3.5.0 (2009-01-26)
------------------
- Removed the dependency on `zope.app.publisher` by moving four simple helper
functions into this package and making the interface for describing the
ZCML content provider directive explicit.
- Typo fix in CSSViewlet docstring.
3.4.2 (2008-01-24)
------------------
- Re-release of 3.4.1 because of brown bag release.
3.4.1 (2008-01-21)
------------------
- bugfix, implemented missing __contains__ method in IViewletManager
- implemented additional viewlet managers offering weight ordered sorting
- implemented additional viewlet managers offering conditional filtering
3.4.1a (2007-4-22)
------------------
- bugfix, added a missing ',' behind zope.i18nmessageid.
- recreated the README.txt removing everything except for the overview.
3.4.0 (2007-10-10)
------------------
- Initial release independent of the main Zope tree.
zope.viewlet-3.7.2/setup.cfg 0000644 0001750 0001750 00000000073 11376754277 015726 0 ustar tseaver tseaver [egg_info]
tag_build =
tag_date = 0
tag_svn_revision = 0
zope.viewlet-3.7.2/README.txt 0000644 0001750 0001750 00000000115 11376754171 015571 0 ustar tseaver tseaver Viewlets provide a generic framework for building pluggable user interfaces.
zope.viewlet-3.7.2/PKG-INFO 0000644 0001750 0001750 00000176672 11376754277 015225 0 ustar tseaver tseaver Metadata-Version: 1.0
Name: zope.viewlet
Version: 3.7.2
Summary: Zope Viewlets
Home-page: http://pypi.python.org/pypi/zope.viewlet
Author: Zope Foundation and Contributors
Author-email: zope-dev@zope.org
License: ZPL 2.1
Description: Viewlets provide a generic framework for building pluggable user interfaces.
Detailed Documentation
**********************
=============================
Viewlets and Viewlet Managers
=============================
Let's start with some motivation. Using content providers allows us to insert
one piece of HTML content. In most Web development, however, you are often
interested in defining some sort of region and then allow developers to
register content for those regions.
>>> from zope.viewlet import interfaces
Design Notes
------------
As mentioned above, besides inserting snippets of HTML at places, we more
frequently want to define a region in our page and allow specialized content
providers to be inserted based on configuration. Those specialized content
providers are known as viewlets and are only available inside viewlet
managers, which are just a more complex example of content providers.
Unfortunately, the Java world does not implement this layer separately. The
viewlet manager is most similar to a Java "channel", but we decided against
using this name, since it is very generic and not very meaningful. The viewlet
has no Java counterpart, since Java does not implement content providers using
a component architecture and thus does not register content providers
specifically for viewlet managers, which I believe makes the Java
implementation less useful as a generic concept. In fact, the main design
goal in the Java world is the implementation of reusable and sharable
portlets. The scope for Zope 3 is larger, since we want to provide a generic
framework for building pluggable user interfaces.
The Viewlet Manager
-------------------
In this implementation of viewlets, those regions are just content providers
called viewlet managers that manage a special type of content providers known
as viewlets. Every viewlet manager handles the viewlets registered for it:
>>> class ILeftColumn(interfaces.IViewletManager):
... """Viewlet manager located in the left column."""
You can then create a viewlet manager using this interface now:
>>> from zope.viewlet import manager
>>> LeftColumn = manager.ViewletManager('left', ILeftColumn)
Now we have to instantiate it:
>>> import zope.interface
>>> class Content(object):
... zope.interface.implements(zope.interface.Interface)
>>> content = Content()
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> from zope.publisher.interfaces.browser import IBrowserView
>>> class View(object):
... zope.interface.implements(IBrowserView)
... def __init__(self, context, request):
... pass
>>> view = View(content, request)
>>> leftColumn = LeftColumn(content, request, view)
So initially nothing gets rendered:
>>> leftColumn.update()
>>> leftColumn.render()
u''
But now we register some viewlets for the manager
>>> import zope.component
>>> from zope.publisher.interfaces.browser import IDefaultBrowserLayer
>>> class WeatherBox(object):
... zope.interface.implements(interfaces.IViewlet)
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
...
... def update(self):
... pass
...
... def render(self):
... return u'
'
>>> defineChecker(SportBox, viewletChecker)
>>> zope.component.provideAdapter(
... SportBox,
... (zope.interface.Interface, IDefaultBrowserLayer,
... IBrowserView, ILeftColumn),
... interfaces.IViewlet, name='sport')
and thus the left column is filled. Note that also events get fired
before viewlets are updated. We register a simple handler to
demonstrate this behaviour.
>>> from zope.contentprovider.interfaces import IBeforeUpdateEvent
>>> events = []
>>> def handler(ev):
... events.append(ev)
>>> zope.component.provideHandler(handler, (IBeforeUpdateEvent,))
>>> leftColumn.update()
>>> [(ev, ev.object.__class__.__name__) for ev in events]
[(, 'SportBox'),
(, 'WeatherBox')]
>>> print leftColumn.render()
Patriots (23) : Steelers (7)
It is sunny today!
But this is of course pretty lame, since there is no way of specifying how the
viewlets are put together. But we have a solution. The second argument of the
``ViewletManager()`` function is a template in which we can specify how the
viewlets are put together:
>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> leftColTemplate = os.path.join(temp_dir, 'leftCol.pt')
>>> open(leftColTemplate, 'w').write('''
...
...
...
... ''')
>>> LeftColumn = manager.ViewletManager('left', ILeftColumn,
... template=leftColTemplate)
>>> leftColumn = LeftColumn(content, request, view)
TODO: Fix this silly thing; viewlets should be directly available.
As you can see, the viewlet manager provides a global ``options/viewlets``
variable that is an iterable of all the available viewlets in the correct
order:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
It is sunny today!
If a viewlet provides ILocation the ``__name__`` attribute of the
viewlet is set to the name under which the viewlet is registered.
>>> [getattr(viewlet, '__name__', None) for viewlet in leftColumn.viewlets]
[u'sport', None]
You can also lookup the viewlets directly for management purposes:
>>> leftColumn['weather']
>>> leftColumn.get('weather')
The viewlet manager also provides the __contains__ method defined in
IReadMapping:
>>> 'weather' in leftColumn
True
>>> 'unknown' in leftColumn
False
If the viewlet is not found, then the expected behavior is provided:
>>> leftColumn['stock']
Traceback (most recent call last):
...
ComponentLookupError: No provider with name `stock` found.
>>> leftColumn.get('stock') is None
True
Customizing the default Viewlet Manager
---------------------------------------
One important feature of any viewlet manager is to be able to filter and sort
the viewlets it is displaying. The default viewlet manager that we have been
using in the tests above, supports filtering by access availability and
sorting via the viewlet's ``__cmp__()`` method (default). You can easily
override this default policy by providing a base viewlet manager class.
In our case we will manage the viewlets using a global list:
>>> shown = ['weather', 'sport']
The viewlet manager base class now uses this list:
>>> class ListViewletManager(object):
...
... def filter(self, viewlets):
... viewlets = super(ListViewletManager, self).filter(viewlets)
... return [(name, viewlet)
... for name, viewlet in viewlets
... if name in shown]
...
... def sort(self, viewlets):
... viewlets = dict(viewlets)
... return [(name, viewlets[name]) for name in shown]
Let's now create a new viewlet manager:
>>> LeftColumn = manager.ViewletManager(
... 'left', ILeftColumn, bases=(ListViewletManager,),
... template=leftColTemplate)
>>> leftColumn = LeftColumn(content, request, view)
So we get the weather box first and the sport box second:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
It is sunny today!
Patriots (23) : Steelers (7)
Now let's change the order...
>>> shown.reverse()
and the order should switch as well:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
It is sunny today!
Of course, we also can remove a shown viewlet:
>>> weather = shown.pop()
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
WeightOrderedViewletManager
---------------------------
The weight ordered viewlet manager offers ordering viewlets by a additional
weight argument. Viewlets which doesn't provide a weight attribute will get
a weight of 0 (zero).
Let's define a new column:
>>> class IWeightedColumn(interfaces.IViewletManager):
... """Column with weighted viewlet manager."""
First register a template for the weight ordered viewlet manager:
>>> weightedColTemplate = os.path.join(temp_dir, 'weightedColTemplate.pt')
>>> open(weightedColTemplate, 'w').write('''
...
...
...
... ''')
And create a new weight ordered viewlet manager:
>>> from zope.viewlet.manager import WeightOrderedViewletManager
>>> WeightedColumn = manager.ViewletManager(
... 'left', IWeightedColumn, bases=(WeightOrderedViewletManager,),
... template=weightedColTemplate)
>>> weightedColumn = WeightedColumn(content, request, view)
Let's create some viewlets:
>>> from zope.viewlet import viewlet
>>> class FirstViewlet(viewlet.ViewletBase):
...
... weight = 1
...
... def render(self):
... return u'
ConditionalViewletManager
-------------------------
The conditional ordered viewlet manager offers ordering viewlets by a
additional weight argument and filters by the available attribute if a
supported by the viewlet. Viewlets which doesn't provide a available attribute
will not get skipped. The default weight value for viewlets which doesn't
provide a weight attribute is 0 (zero).
Let's define a new column:
>>> class IConditionalColumn(interfaces.IViewletManager):
... """Column with weighted viewlet manager."""
First register a template for the weight ordered viewlet manager:
>>> conditionalColTemplate = os.path.join(temp_dir,
... 'conditionalColTemplate.pt')
>>> open(conditionalColTemplate, 'w').write('''
...
...
...
... ''')
And create a new conditional viewlet manager:
>>> from zope.viewlet.manager import ConditionalViewletManager
>>> ConditionalColumn = manager.ViewletManager(
... 'left', IConditionalColumn, bases=(ConditionalViewletManager,),
... template=conditionalColTemplate)
>>> conditionalColumn = ConditionalColumn(content, request, view)
Let's create some viewlets. We also use the previous viewlets supporting no
weight and or no available attribute:
>>> from zope.viewlet import viewlet
>>> class AvailableViewlet(viewlet.ViewletBase):
...
... weight = 4
...
... available = True
...
... def render(self):
... return u'
Viewlet Base Classes
--------------------
To make the creation of viewlets simpler, a set of useful base classes and
helper functions are provided.
The first class is a base class that simply defines the constructor:
>>> base = viewlet.ViewletBase('context', 'request', 'view', 'manager')
>>> base.context
'context'
>>> base.request
'request'
>>> base.__parent__
'view'
>>> base.manager
'manager'
But a default ``render()`` method implementation is not provided:
>>> base.render()
Traceback (most recent call last):
...
NotImplementedError: `render` method must be implemented by subclass.
If you have already an existing class that produces the HTML content in some
method, then the ``SimpleAttributeViewlet`` might be for you, since it can be
used to convert any class quickly into a viewlet:
>>> class FooViewlet(viewlet.SimpleAttributeViewlet):
... __page_attribute__ = 'foo'
...
... def foo(self):
... return 'output'
The `__page_attribute__` attribute provides the name of the function to call for
rendering.
>>> foo = FooViewlet('context', 'request', 'view', 'manager')
>>> foo.foo()
'output'
>>> foo.render()
'output'
If you specify `render` as the attribute an error is raised to prevent
infinite recursion:
>>> foo.__page_attribute__ = 'render'
>>> foo.render()
Traceback (most recent call last):
...
AttributeError: render
The same is true if the specified attribute does not exist:
>>> foo.__page_attribute__ = 'bar'
>>> foo.render()
Traceback (most recent call last):
...
AttributeError: 'FooViewlet' object has no attribute 'bar'
To create simple template-based viewlets you can use the
``SimpleViewletClass()`` function. This function is very similar to its view
equivalent and is used by the ZCML directives to create viewlets. The result
of this function call will be a fully functional viewlet class. Let's start by
simply specifying a template only:
>>> template = os.path.join(temp_dir, 'demoTemplate.pt')
>>> open(template, 'w').write('''
Now let's additionally specify a class that can provide additional features:
>>> class MyViewlet(object):
... myAttribute = 8
>>> Demo = viewlet.SimpleViewletClass(template, bases=(MyViewlet,))
>>> MyViewlet in Demo.__bases__
True
>>> Demo(content, request, view, manager).myAttribute
8
The final important feature is the ability to pass in further attributes to
the class:
>>> Demo = viewlet.SimpleViewletClass(
... template, attributes={'here': 'now', 'lucky': 3})
>>> demo = Demo(content, request, view, manager)
>>> demo.here
'now'
>>> demo.lucky
3
As for all views, they must provide a name that can also be passed to the
function:
>>> Demo = viewlet.SimpleViewletClass(template, name='demoViewlet')
>>> demo = Demo(content, request, view, manager)
>>> demo.__name__
'demoViewlet'
In addition to the the generic viewlet code above, the package comes with two
viewlet base classes and helper functions for inserting CSS and Javascript
links into HTML headers, since those two are so very common. I am only going
to demonstrate the helper functions here, since those demonstrations will
fully demonstrate the functionality of the base classes as well.
The viewlet will look up the resource it was given and tries to produce the
absolute URL for it:
>>> class JSResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/resource.js'
>>> zope.component.provideAdapter(
... JSResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='resource.js')
>>> JSViewlet = viewlet.JavaScriptViewlet('resource.js')
>>> print JSViewlet(content, request, view, manager).render().strip()
There is also a javascript viewlet base class which knows how to render more
then one javascript resource file:
>>> class JSSecondResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/second-resource.js'
>>> zope.component.provideAdapter(
... JSSecondResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='second-resource.js')
>>> JSBundleViewlet = viewlet.JavaScriptBundleViewlet(('resource.js',
... 'second-resource.js'))
>>> print JSBundleViewlet(content, request, view, manager).render().strip()
The same works for the CSS resource viewlet:
>>> class CSSResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/resource.css'
>>> zope.component.provideAdapter(
... CSSResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='resource.css')
>>> CSSViewlet = viewlet.CSSViewlet('resource.css')
>>> print CSSViewlet(content, request, view, manager).render().strip()
You can also change the media type and the rel attribute:
>>> CSSViewlet = viewlet.CSSViewlet('resource.css', media='print', rel='css')
>>> print CSSViewlet(content, request, view, manager).render().strip()
There is also a bundle viewlet for CSS links:
>>> class CSSPrintResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/print-resource.css'
>>> zope.component.provideAdapter(
... CSSPrintResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='print-resource.css')
>>> items = []
>>> items.append({'path':'resource.css', 'rel':'stylesheet', 'media':'all'})
>>> items.append({'path':'print-resource.css', 'media':'print'})
>>> CSSBundleViewlet = viewlet.CSSBundleViewlet(items)
>>> print CSSBundleViewlet(content, request, view, manager).render().strip()
A Complex Example
-----------------
The Data
~~~~~~~~
So far we have only demonstrated simple (maybe overly trivial) use cases of
the viewlet system. In the following example, we are going to develop a
generic contents view for files. The step is to create a file component:
>>> class IFile(zope.interface.Interface):
... data = zope.interface.Attribute('Data of file.')
>>> class File(object):
... zope.interface.implements(IFile)
... def __init__(self, data=''):
... self.__name__ = ''
... self.data = data
Since we want to also provide the size of a file, here a simple implementation
of the ``ISized`` interface:
>>> from zope import size
>>> class FileSized(object):
... zope.interface.implements(size.interfaces.ISized)
... zope.component.adapts(IFile)
...
... def __init__(self, file):
... self.file = file
...
... def sizeForSorting(self):
... return 'byte', len(self.file.data)
...
... def sizeForDisplay(self):
... return '%i bytes' %len(self.file.data)
>>> zope.component.provideAdapter(FileSized)
We also need a container to which we can add files:
>>> class Container(dict):
... def __setitem__(self, name, value):
... value.__name__ = name
... super(Container, self).__setitem__(name, value)
Here is some sample data:
>>> container = Container()
>>> container['test.txt'] = File('Hello World!')
>>> container['mypage.html'] = File('Hello World!')
>>> container['data.xml'] = File('Hello World!')
The View
~~~~~~~~
The contents view of the container should iterate through the container and
represent the files in a table:
>>> contentsTemplate = os.path.join(temp_dir, 'contents.pt')
>>> open(contentsTemplate, 'w').write('''
...
...
...
Contents
...
...
...
... ''')
>>> from zope.browserpage.simpleviewclass import SimpleViewClass
>>> Contents = SimpleViewClass(contentsTemplate, name='contents.html')
The Viewlet Manager
~~~~~~~~~~~~~~~~~~~
Now we have to write our own viewlet manager. In this case we cannot use the
default implementation, since the viewlets will be looked up for each
different item:
>>> shownColumns = []
>>> class ContentsViewletManager(object):
... zope.interface.implements(interfaces.IViewletManager)
... index = None
...
... def __init__(self, context, request, view):
... self.context = context
... self.request = request
... self.__parent__ = view
...
... def update(self):
... rows = []
... for name, value in self.context.items():
... rows.append(
... [zope.component.getMultiAdapter(
... (value, self.request, self.__parent__, self),
... interfaces.IViewlet, name=colname)
... for colname in shownColumns])
... [entry.update() for entry in rows[-1]]
... self.rows = rows
...
... def render(self, *args, **kw):
... return self.index(*args, **kw)
Now we need a template to produce the contents table:
>>> tableTemplate = os.path.join(temp_dir, 'table.pt')
>>> open(tableTemplate, 'w').write('''
...
...
...
...
...
...
...
... ''')
From the two pieces above, we can generate the final viewlet manager class and
register it (it's a bit tedious, I know):
>>> from zope.browserpage import ViewPageTemplateFile
>>> ContentsViewletManager = type(
... 'ContentsViewletManager', (ContentsViewletManager,),
... {'index': ViewPageTemplateFile(tableTemplate)})
>>> zope.component.provideAdapter(
... ContentsViewletManager,
... (Container, IDefaultBrowserLayer, zope.interface.Interface),
... interfaces.IViewletManager, name='contents')
Since we have not defined any viewlets yet, the table is totally empty:
>>> contents = Contents(container, request)
>>> print contents().strip()
Contents
The Viewlets and the Final Result
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Now let's create a first viewlet for the manager...
>>> class NameViewlet(object):
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
... self.context = context
...
... def update(self):
... pass
...
... def render(self):
... return self.context.__name__
and register it:
>>> zope.component.provideAdapter(
... NameViewlet,
... (IFile, IDefaultBrowserLayer,
... zope.interface.Interface, interfaces.IViewletManager),
... interfaces.IViewlet, name='name')
Note how you register the viewlet on ``IFile`` and not on the container. Now
we should be able to see the name for each file in the container:
>>> print contents().strip()
Contents
Waaa, nothing there! What happened? Well, we have to tell our user preferences
that we want to see the name as a column in the table:
>>> shownColumns = ['name']
>>> print contents().strip()
Contents
mypage.html
data.xml
test.txt
Let's now write a second viewlet that will display the size of the object for
us:
>>> class SizeViewlet(object):
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
... self.context = context
...
... def update(self):
... pass
...
... def render(self):
... return size.interfaces.ISized(self.context).sizeForDisplay()
>>> zope.component.provideAdapter(
... SizeViewlet,
... (IFile, IDefaultBrowserLayer,
... zope.interface.Interface, interfaces.IViewletManager),
... interfaces.IViewlet, name='size')
After we added it to the list of shown columns,
>>> shownColumns = ['name', 'size']
we can see an entry for it:
>>> print contents().strip()
Contents
mypage.html
38 bytes
data.xml
31 bytes
test.txt
12 bytes
If we switch the two columns around,
>>> shownColumns = ['size', 'name']
the result will be
>>> print contents().strip()
Contents
38 bytes
mypage.html
31 bytes
data.xml
12 bytes
test.txt
Supporting Sorting
~~~~~~~~~~~~~~~~~~
Oftentimes you also want to batch and sort the entries in a table. Since those
two features are not part of the view logic, they should be treated with
independent components. In this example, we are going to only implement
sorting using a simple utility:
>>> class ISorter(zope.interface.Interface):
...
... def sort(values):
... """Sort the values."""
>>> class SortByName(object):
... zope.interface.implements(ISorter)
...
... def sort(self, values):
... return sorted(values, lambda x, y: cmp(x.__name__, y.__name__))
>>> zope.component.provideUtility(SortByName(), name='name')
>>> class SortBySize(object):
... zope.interface.implements(ISorter)
...
... def sort(self, values):
... return sorted(
... values,
... lambda x, y: cmp(size.interfaces.ISized(x).sizeForSorting(),
... size.interfaces.ISized(y).sizeForSorting()))
>>> zope.component.provideUtility(SortBySize(), name='size')
Note that we decided to give the sorter utilities the same name as the
corresponding viewlet. This convention will make our implementation of the
viewlet manager much simpler:
>>> sortByColumn = ''
>>> class SortedContentsViewletManager(object):
... zope.interface.implements(interfaces.IViewletManager)
... index = None
...
... def __init__(self, context, request, view):
... self.context = context
... self.request = request
... self.__parent__ = view
...
... def update(self):
... values = self.context.values()
...
... if sortByColumn:
... sorter = zope.component.queryUtility(ISorter, sortByColumn)
... if sorter:
... values = sorter.sort(values)
...
... rows = []
... for value in values:
... rows.append(
... [zope.component.getMultiAdapter(
... (value, self.request, self.__parent__, self),
... interfaces.IViewlet, name=colname)
... for colname in shownColumns])
... [entry.update() for entry in rows[-1]]
... self.rows = rows
...
... def render(self, *args, **kw):
... return self.index(*args, **kw)
As you can see, the concern of sorting is cleanly separated from generating
the view code. In MVC terms that means that the controller (sort) is logically
separated from the view (viewlets). Let's now do the registration dance for
the new viewlet manager. We simply override the existing registration:
>>> SortedContentsViewletManager = type(
... 'SortedContentsViewletManager', (SortedContentsViewletManager,),
... {'index': ViewPageTemplateFile(tableTemplate)})
>>> zope.component.provideAdapter(
... SortedContentsViewletManager,
... (Container, IDefaultBrowserLayer, zope.interface.Interface),
... interfaces.IViewletManager, name='contents')
Finally we sort the contents by name:
>>> shownColumns = ['name', 'size']
>>> sortByColumn = 'name'
>>> print contents().strip()
Contents
data.xml
31 bytes
mypage.html
38 bytes
test.txt
12 bytes
Now let's sort by size:
>>> sortByColumn = 'size'
>>> print contents().strip()
Contents
test.txt
12 bytes
data.xml
31 bytes
mypage.html
38 bytes
That's it! As you can see, in a few steps we have built a pretty flexible
contents view with selectable columns and sorting. However, there is a lot of
room for extending this example:
- Table Header: The table header cell for each column should be a different
type of viewlet, but registered under the same name. The column header
viewlet also adapts the container not the item. The header column should
also be able to control the sorting.
- Batching: A simple implementation of batching should work very similar to
the sorting feature. Of course, efficient implementations should somehow
combine batching and sorting more effectively.
- Sorting in ascending and descending order: Currently, you can only sort from
the smallest to the highest value; however, this limitation is almost
superficial and can easily be removed by making the sorters a bit more
flexible.
- Further Columns: For a real application, you would want to implement other
columns, of course. You would also probably want some sort of fallback for
the case that a viewlet is not found for a particular container item and
column.
Cleanup
-------
>>> import shutil
>>> shutil.rmtree(temp_dir)
================================
The ``viewletManager`` Directive
================================
The ``viewletManager`` directive allows you to quickly register a new viewlet
manager without worrying about the details of the ``adapter``
directive. Before we can use the directives, we have to register their
handlers by executing the package's meta configuration:
>>> from zope.configuration import xmlconfig
>>> context = xmlconfig.string('''
...
...
...
... ''')
Now we can register a viewlet manager:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Let's make sure the directive has really issued a sensible adapter
registration; to do that, we create some dummy content, request and view
objects:
>>> import zope.interface
>>> class Content(object):
... zope.interface.implements(zope.interface.Interface)
>>> content = Content()
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> from zope.publisher.browser import BrowserView
>>> view = BrowserView(content, request)
Now let's lookup the manager. This particular registration is pretty boring:
>>> import zope.component
>>> from zope.viewlet import interfaces
>>> manager = zope.component.getMultiAdapter(
... (content, request, view),
... interfaces.IViewletManager, name='defaultmanager')
>>> manager
object ...>
>>> interfaces.IViewletManager.providedBy(manager)
True
>>> manager.template is None
True
>>> manager.update()
>>> manager.render()
u''
However, this registration is not very useful, since we did specify a specific
viewlet manager interface, a specific content interface, specific view or
specific layer. This means that all viewlets registered will be found.
The first step to effectively using the viewlet manager directive is to define
a special viewlet manager interface:
>>> class ILeftColumn(interfaces.IViewletManager):
... """Left column of my page."""
Now we can register register a manager providing this interface:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> manager = zope.component.getMultiAdapter(
... (content, request, view), ILeftColumn, name='leftcolumn')
>>> manager
object ...>
>>> ILeftColumn.providedBy(manager)
True
>>> manager.template is None
True
>>> manager.update()
>>> manager.render()
u''
Next let's see what happens, if we specify a template for the viewlet manager:
>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> leftColumnTemplate = os.path.join(temp_dir, 'leftcolumn.pt')
>>> open(leftColumnTemplate, 'w').write('''
...
Additionally you can specify a class that will serve as a base to the default
viewlet manager or be a viewlet manager in its own right. In our case we will
provide a custom implementation of the ``sort()`` method, which will sort by a
weight attribute in the viewlet:
>>> class WeightBasedSorting(object):
... def sort(self, viewlets):
... return sorted(viewlets,
... lambda x, y: cmp(x[1].weight, y[1].weight))
>>> context = xmlconfig.string('''
...
...
...
... ''' %leftColumnTemplate, context=context)
>>> manager = zope.component.getMultiAdapter(
... (content, request, view), ILeftColumn, name='leftcolumn')
>>> manager
object ...>
>>> manager.__class__.__bases__
(,
)
>>> ILeftColumn.providedBy(manager)
True
>>> manager.template
...>>
>>> manager.update()
>>> print manager.render().strip()
Finally, if a non-existent template is specified, an error is raised:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-7.8
ConfigurationError: ('No such file', '...foo.pt')
=========================
The ``viewlet`` Directive
=========================
Now that we have a viewlet manager, we have to register some viewlets for
it. The ``viewlet`` directive is similar to the ``viewletManager`` directive,
except that the viewlet is also registered for a particular manager interface,
as seen below:
>>> weatherTemplate = os.path.join(temp_dir, 'weather.pt')
>>> open(weatherTemplate, 'w').write('''
...
sunny
... ''')
>>> context = xmlconfig.string('''
...
...
...
... ''' % weatherTemplate, context=context)
If we look into the adapter registry, we will find the viewlet:
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='weather')
>>> viewlet.render().strip()
u'
sunny
'
>>> viewlet.extra_string_attributes
u'can be specified'
The manager now also gives us the output of the one and only viewlet:
>>> manager.update()
>>> print manager.render().strip()
sunny
Let's now ensure that we can also specify a viewlet class:
>>> class Weather(object):
... weight = 0
>>> context = xmlconfig.string('''
...
...
...
... ''' % weatherTemplate, context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='weather2')
>>> viewlet().strip()
u'
sunny
'
Okay, so the template-driven cases work. But just specifying a class should
also work:
>>> class Sport(object):
... weight = 0
... def __call__(self):
... return u'Red Sox vs. White Sox'
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet, name='sport')
>>> viewlet()
u'Red Sox vs. White Sox'
It should also be possible to specify an alternative attribute of the class to
be rendered upon calling the viewlet:
>>> class Stock(object):
... weight = 0
... def getStockTicker(self):
... return u'SRC $5.19'
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='stock')
>>> viewlet.render()
u'SRC $5.19'
A final feature the ``viewlet`` directive is that it supports the
specification of any number of keyword arguments:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='stock2')
>>> viewlet.weight
u'8'
Error Scenarios
---------------
Neither the class or template have been specified:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-7.8
ConfigurationError: Must specify a class or template
The specified attribute is not ``__call__``, but also a template has been
specified:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-9.8
ConfigurationError: Attribute and template cannot be used together.
Now, we are not specifying a template, but a class that does not have the
specified attribute:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-9.8
ConfigurationError: The provided class doesn't have the specified attribute
Cleanup
-------
>>> import shutil
>>> shutil.rmtree(temp_dir)
=======
CHANGES
=======
3.7.2 (2010-05-25)
------------------
- Fixed unit tests broken under Python 2.4 by the switch to the standard
library ``doctest`` module.
3.7.1 (2010-04-30)
------------------
- Removed use of 'zope.testing.doctest' in favor of stdlib's 'doctest.
- Fixed dubious quoting in metadirectives.py. Closes
https://bugs.launchpad.net/zope2/+bug/143774.
3.7.0 (2009-12-22)
------------------
- Depend on zope.browserpage in favor of zope.app.pagetemplate.
3.6.1 (2009-08-29)
------------------
- Fixed unit tests in README.txt.
3.6.0 (2009-08-02)
------------------
- Optimize the the script tag for the JS viewlet. This makes YSlow happy.
- Remove ZCML slugs and old zpkg-related files.
- Drop all testing dependncies except ``zope.testing``.
3.5.0 (2009-01-26)
------------------
- Removed the dependency on `zope.app.publisher` by moving four simple helper
functions into this package and making the interface for describing the
ZCML content provider directive explicit.
- Typo fix in CSSViewlet docstring.
3.4.2 (2008-01-24)
------------------
- Re-release of 3.4.1 because of brown bag release.
3.4.1 (2008-01-21)
------------------
- bugfix, implemented missing __contains__ method in IViewletManager
- implemented additional viewlet managers offering weight ordered sorting
- implemented additional viewlet managers offering conditional filtering
3.4.1a (2007-4-22)
------------------
- bugfix, added a missing ',' behind zope.i18nmessageid.
- recreated the README.txt removing everything except for the overview.
3.4.0 (2007-10-10)
------------------
- Initial release independent of the main Zope tree.
Keywords: zope web html ui viewlet pattern
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Environment :: Web Environment
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Zope Public License
Classifier: Programming Language :: Python
Classifier: Natural Language :: English
Classifier: Operating System :: OS Independent
Classifier: Topic :: Internet :: WWW/HTTP
Classifier: Framework :: Zope3
zope.viewlet-3.7.2/bootstrap.py 0000644 0001750 0001750 00000007422 11376754171 016472 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2006 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Bootstrap a buildout-based project
Simply run this script in a directory containing a buildout.cfg.
The script accepts buildout command-line options, so you can
use the -c option to specify an alternate configuration file.
$Id: bootstrap.py 111805 2010-04-30 22:21:55Z hannosch $
"""
import os, shutil, sys, tempfile, urllib2
from optparse import OptionParser
tmpeggs = tempfile.mkdtemp()
is_jython = sys.platform.startswith('java')
# parsing arguments
parser = OptionParser()
parser.add_option("-v", "--version", dest="version",
help="use a specific zc.buildout version")
parser.add_option("-d", "--distribute",
action="store_true", dest="distribute", default=False,
help="Use Disribute rather than Setuptools.")
parser.add_option("-c", None, action="store", dest="config_file",
help=("Specify the path to the buildout configuration "
"file to be used."))
options, args = parser.parse_args()
# if -c was provided, we push it back into args for buildout' main function
if options.config_file is not None:
args += ['-c', options.config_file]
if options.version is not None:
VERSION = '==%s' % options.version
else:
VERSION = ''
USE_DISTRIBUTE = options.distribute
args = args + ['bootstrap']
to_reload = False
try:
import pkg_resources
if not hasattr(pkg_resources, '_distribute'):
to_reload = True
raise ImportError
except ImportError:
ez = {}
if USE_DISTRIBUTE:
exec urllib2.urlopen('http://python-distribute.org/distribute_setup.py'
).read() in ez
ez['use_setuptools'](to_dir=tmpeggs, download_delay=0, no_fake=True)
else:
exec urllib2.urlopen('http://peak.telecommunity.com/dist/ez_setup.py'
).read() in ez
ez['use_setuptools'](to_dir=tmpeggs, download_delay=0)
if to_reload:
reload(pkg_resources)
else:
import pkg_resources
if sys.platform == 'win32':
def quote(c):
if ' ' in c:
return '"%s"' % c # work around spawn lamosity on windows
else:
return c
else:
def quote (c):
return c
cmd = 'from setuptools.command.easy_install import main; main()'
ws = pkg_resources.working_set
if USE_DISTRIBUTE:
requirement = 'distribute'
else:
requirement = 'setuptools'
if is_jython:
import subprocess
assert subprocess.Popen([sys.executable] + ['-c', quote(cmd), '-mqNxd',
quote(tmpeggs), 'zc.buildout' + VERSION],
env=dict(os.environ,
PYTHONPATH=
ws.find(pkg_resources.Requirement.parse(requirement)).location
),
).wait() == 0
else:
assert os.spawnle(
os.P_WAIT, sys.executable, quote (sys.executable),
'-c', quote (cmd), '-mqNxd', quote (tmpeggs), 'zc.buildout' + VERSION,
dict(os.environ,
PYTHONPATH=
ws.find(pkg_resources.Requirement.parse(requirement)).location
),
) == 0
ws.add_entry(tmpeggs)
ws.require('zc.buildout' + VERSION)
import zc.buildout.buildout
zc.buildout.buildout.main(args)
shutil.rmtree(tmpeggs)
zope.viewlet-3.7.2/setup.py 0000644 0001750 0001750 00000005711 11376754171 015614 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2006 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
# This package is developed by the Zope Toolkit project, documented here:
# http://docs.zope.org/zopetoolkit
# When developing and releasing this package, please follow the documented
# Zope Toolkit policies as described by this documentation.
##############################################################################
"""Setup for zope.viewlet package
$Id: setup.py 112690 2010-05-25 14:02:00Z tseaver $
"""
import os
from setuptools import setup, find_packages
def read(*rnames):
return open(os.path.join(os.path.dirname(__file__), *rnames)).read()
setup(name='zope.viewlet',
version = '3.7.2',
author='Zope Foundation and Contributors',
author_email='zope-dev@zope.org',
description='Zope Viewlets',
long_description=(
read('README.txt')
+ '\n\n' +
'Detailed Documentation\n' +
'**********************\n\n'
+ '\n\n' +
read('src', 'zope', 'viewlet', 'README.txt')
+ '\n\n' +
read('src', 'zope', 'viewlet', 'directives.txt')
+ '\n\n' +
read('CHANGES.txt')
),
keywords = "zope web html ui viewlet pattern",
classifiers = [
'Development Status :: 5 - Production/Stable',
'Environment :: Web Environment',
'Intended Audience :: Developers',
'License :: OSI Approved :: Zope Public License',
'Programming Language :: Python',
'Natural Language :: English',
'Operating System :: OS Independent',
'Topic :: Internet :: WWW/HTTP',
'Framework :: Zope3'],
url='http://pypi.python.org/pypi/zope.viewlet',
license='ZPL 2.1',
packages=find_packages('src'),
package_dir = {'': 'src'},
namespace_packages=['zope'],
extras_require = dict(
test=[
'zope.testing',
'zope.size',
]),
install_requires=[
'setuptools',
'zope.browserpage>=3.10.1',
'zope.component',
'zope.configuration',
'zope.contentprovider',
'zope.event',
'zope.i18nmessageid',
'zope.interface',
'zope.location',
'zope.publisher',
'zope.schema',
'zope.security',
'zope.traversing',
],
include_package_data = True,
zip_safe = False,
)
zope.viewlet-3.7.2/src/ 0000755 0001750 0001750 00000000000 11376754277 014674 5 ustar tseaver tseaver zope.viewlet-3.7.2/src/zope.viewlet.egg-info/ 0000755 0001750 0001750 00000000000 11376754277 021021 5 ustar tseaver tseaver zope.viewlet-3.7.2/src/zope.viewlet.egg-info/SOURCES.txt 0000644 0001750 0001750 00000001631 11376754277 022706 0 ustar tseaver tseaver CHANGES.txt
COPYRIGHT.txt
LICENSE.txt
README.txt
bootstrap.py
buildout.cfg
setup.py
src/zope/__init__.py
src/zope.viewlet.egg-info/PKG-INFO
src/zope.viewlet.egg-info/SOURCES.txt
src/zope.viewlet.egg-info/dependency_links.txt
src/zope.viewlet.egg-info/namespace_packages.txt
src/zope.viewlet.egg-info/not-zip-safe
src/zope.viewlet.egg-info/requires.txt
src/zope.viewlet.egg-info/top_level.txt
src/zope/viewlet/README.txt
src/zope/viewlet/__init__.py
src/zope/viewlet/communicating-viewlets.txt
src/zope/viewlet/configure.zcml
src/zope/viewlet/css_bundle_viewlet.pt
src/zope/viewlet/css_viewlet.pt
src/zope/viewlet/directives.txt
src/zope/viewlet/interfaces.py
src/zope/viewlet/javascript_bundle_viewlet.pt
src/zope/viewlet/javascript_viewlet.pt
src/zope/viewlet/manager.py
src/zope/viewlet/meta.zcml
src/zope/viewlet/metaconfigure.py
src/zope/viewlet/metadirectives.py
src/zope/viewlet/tests.py
src/zope/viewlet/viewlet.py zope.viewlet-3.7.2/src/zope.viewlet.egg-info/dependency_links.txt 0000644 0001750 0001750 00000000001 11376754276 025066 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope.viewlet.egg-info/top_level.txt 0000644 0001750 0001750 00000000005 11376754276 023545 0 ustar tseaver tseaver zope
zope.viewlet-3.7.2/src/zope.viewlet.egg-info/namespace_packages.txt 0000644 0001750 0001750 00000000005 11376754276 025346 0 ustar tseaver tseaver zope
zope.viewlet-3.7.2/src/zope.viewlet.egg-info/requires.txt 0000644 0001750 0001750 00000000355 11376754276 023423 0 ustar tseaver tseaver setuptools
zope.browserpage>=3.10.1
zope.component
zope.configuration
zope.contentprovider
zope.event
zope.i18nmessageid
zope.interface
zope.location
zope.publisher
zope.schema
zope.security
zope.traversing
[test]
zope.testing
zope.size zope.viewlet-3.7.2/src/zope.viewlet.egg-info/PKG-INFO 0000644 0001750 0001750 00000176672 11376754276 022140 0 ustar tseaver tseaver Metadata-Version: 1.0
Name: zope.viewlet
Version: 3.7.2
Summary: Zope Viewlets
Home-page: http://pypi.python.org/pypi/zope.viewlet
Author: Zope Foundation and Contributors
Author-email: zope-dev@zope.org
License: ZPL 2.1
Description: Viewlets provide a generic framework for building pluggable user interfaces.
Detailed Documentation
**********************
=============================
Viewlets and Viewlet Managers
=============================
Let's start with some motivation. Using content providers allows us to insert
one piece of HTML content. In most Web development, however, you are often
interested in defining some sort of region and then allow developers to
register content for those regions.
>>> from zope.viewlet import interfaces
Design Notes
------------
As mentioned above, besides inserting snippets of HTML at places, we more
frequently want to define a region in our page and allow specialized content
providers to be inserted based on configuration. Those specialized content
providers are known as viewlets and are only available inside viewlet
managers, which are just a more complex example of content providers.
Unfortunately, the Java world does not implement this layer separately. The
viewlet manager is most similar to a Java "channel", but we decided against
using this name, since it is very generic and not very meaningful. The viewlet
has no Java counterpart, since Java does not implement content providers using
a component architecture and thus does not register content providers
specifically for viewlet managers, which I believe makes the Java
implementation less useful as a generic concept. In fact, the main design
goal in the Java world is the implementation of reusable and sharable
portlets. The scope for Zope 3 is larger, since we want to provide a generic
framework for building pluggable user interfaces.
The Viewlet Manager
-------------------
In this implementation of viewlets, those regions are just content providers
called viewlet managers that manage a special type of content providers known
as viewlets. Every viewlet manager handles the viewlets registered for it:
>>> class ILeftColumn(interfaces.IViewletManager):
... """Viewlet manager located in the left column."""
You can then create a viewlet manager using this interface now:
>>> from zope.viewlet import manager
>>> LeftColumn = manager.ViewletManager('left', ILeftColumn)
Now we have to instantiate it:
>>> import zope.interface
>>> class Content(object):
... zope.interface.implements(zope.interface.Interface)
>>> content = Content()
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> from zope.publisher.interfaces.browser import IBrowserView
>>> class View(object):
... zope.interface.implements(IBrowserView)
... def __init__(self, context, request):
... pass
>>> view = View(content, request)
>>> leftColumn = LeftColumn(content, request, view)
So initially nothing gets rendered:
>>> leftColumn.update()
>>> leftColumn.render()
u''
But now we register some viewlets for the manager
>>> import zope.component
>>> from zope.publisher.interfaces.browser import IDefaultBrowserLayer
>>> class WeatherBox(object):
... zope.interface.implements(interfaces.IViewlet)
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
...
... def update(self):
... pass
...
... def render(self):
... return u'
'
>>> defineChecker(SportBox, viewletChecker)
>>> zope.component.provideAdapter(
... SportBox,
... (zope.interface.Interface, IDefaultBrowserLayer,
... IBrowserView, ILeftColumn),
... interfaces.IViewlet, name='sport')
and thus the left column is filled. Note that also events get fired
before viewlets are updated. We register a simple handler to
demonstrate this behaviour.
>>> from zope.contentprovider.interfaces import IBeforeUpdateEvent
>>> events = []
>>> def handler(ev):
... events.append(ev)
>>> zope.component.provideHandler(handler, (IBeforeUpdateEvent,))
>>> leftColumn.update()
>>> [(ev, ev.object.__class__.__name__) for ev in events]
[(, 'SportBox'),
(, 'WeatherBox')]
>>> print leftColumn.render()
Patriots (23) : Steelers (7)
It is sunny today!
But this is of course pretty lame, since there is no way of specifying how the
viewlets are put together. But we have a solution. The second argument of the
``ViewletManager()`` function is a template in which we can specify how the
viewlets are put together:
>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> leftColTemplate = os.path.join(temp_dir, 'leftCol.pt')
>>> open(leftColTemplate, 'w').write('''
...
...
...
... ''')
>>> LeftColumn = manager.ViewletManager('left', ILeftColumn,
... template=leftColTemplate)
>>> leftColumn = LeftColumn(content, request, view)
TODO: Fix this silly thing; viewlets should be directly available.
As you can see, the viewlet manager provides a global ``options/viewlets``
variable that is an iterable of all the available viewlets in the correct
order:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
It is sunny today!
If a viewlet provides ILocation the ``__name__`` attribute of the
viewlet is set to the name under which the viewlet is registered.
>>> [getattr(viewlet, '__name__', None) for viewlet in leftColumn.viewlets]
[u'sport', None]
You can also lookup the viewlets directly for management purposes:
>>> leftColumn['weather']
>>> leftColumn.get('weather')
The viewlet manager also provides the __contains__ method defined in
IReadMapping:
>>> 'weather' in leftColumn
True
>>> 'unknown' in leftColumn
False
If the viewlet is not found, then the expected behavior is provided:
>>> leftColumn['stock']
Traceback (most recent call last):
...
ComponentLookupError: No provider with name `stock` found.
>>> leftColumn.get('stock') is None
True
Customizing the default Viewlet Manager
---------------------------------------
One important feature of any viewlet manager is to be able to filter and sort
the viewlets it is displaying. The default viewlet manager that we have been
using in the tests above, supports filtering by access availability and
sorting via the viewlet's ``__cmp__()`` method (default). You can easily
override this default policy by providing a base viewlet manager class.
In our case we will manage the viewlets using a global list:
>>> shown = ['weather', 'sport']
The viewlet manager base class now uses this list:
>>> class ListViewletManager(object):
...
... def filter(self, viewlets):
... viewlets = super(ListViewletManager, self).filter(viewlets)
... return [(name, viewlet)
... for name, viewlet in viewlets
... if name in shown]
...
... def sort(self, viewlets):
... viewlets = dict(viewlets)
... return [(name, viewlets[name]) for name in shown]
Let's now create a new viewlet manager:
>>> LeftColumn = manager.ViewletManager(
... 'left', ILeftColumn, bases=(ListViewletManager,),
... template=leftColTemplate)
>>> leftColumn = LeftColumn(content, request, view)
So we get the weather box first and the sport box second:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
It is sunny today!
Patriots (23) : Steelers (7)
Now let's change the order...
>>> shown.reverse()
and the order should switch as well:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
It is sunny today!
Of course, we also can remove a shown viewlet:
>>> weather = shown.pop()
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
WeightOrderedViewletManager
---------------------------
The weight ordered viewlet manager offers ordering viewlets by a additional
weight argument. Viewlets which doesn't provide a weight attribute will get
a weight of 0 (zero).
Let's define a new column:
>>> class IWeightedColumn(interfaces.IViewletManager):
... """Column with weighted viewlet manager."""
First register a template for the weight ordered viewlet manager:
>>> weightedColTemplate = os.path.join(temp_dir, 'weightedColTemplate.pt')
>>> open(weightedColTemplate, 'w').write('''
...
...
...
... ''')
And create a new weight ordered viewlet manager:
>>> from zope.viewlet.manager import WeightOrderedViewletManager
>>> WeightedColumn = manager.ViewletManager(
... 'left', IWeightedColumn, bases=(WeightOrderedViewletManager,),
... template=weightedColTemplate)
>>> weightedColumn = WeightedColumn(content, request, view)
Let's create some viewlets:
>>> from zope.viewlet import viewlet
>>> class FirstViewlet(viewlet.ViewletBase):
...
... weight = 1
...
... def render(self):
... return u'
ConditionalViewletManager
-------------------------
The conditional ordered viewlet manager offers ordering viewlets by a
additional weight argument and filters by the available attribute if a
supported by the viewlet. Viewlets which doesn't provide a available attribute
will not get skipped. The default weight value for viewlets which doesn't
provide a weight attribute is 0 (zero).
Let's define a new column:
>>> class IConditionalColumn(interfaces.IViewletManager):
... """Column with weighted viewlet manager."""
First register a template for the weight ordered viewlet manager:
>>> conditionalColTemplate = os.path.join(temp_dir,
... 'conditionalColTemplate.pt')
>>> open(conditionalColTemplate, 'w').write('''
...
...
...
... ''')
And create a new conditional viewlet manager:
>>> from zope.viewlet.manager import ConditionalViewletManager
>>> ConditionalColumn = manager.ViewletManager(
... 'left', IConditionalColumn, bases=(ConditionalViewletManager,),
... template=conditionalColTemplate)
>>> conditionalColumn = ConditionalColumn(content, request, view)
Let's create some viewlets. We also use the previous viewlets supporting no
weight and or no available attribute:
>>> from zope.viewlet import viewlet
>>> class AvailableViewlet(viewlet.ViewletBase):
...
... weight = 4
...
... available = True
...
... def render(self):
... return u'
Viewlet Base Classes
--------------------
To make the creation of viewlets simpler, a set of useful base classes and
helper functions are provided.
The first class is a base class that simply defines the constructor:
>>> base = viewlet.ViewletBase('context', 'request', 'view', 'manager')
>>> base.context
'context'
>>> base.request
'request'
>>> base.__parent__
'view'
>>> base.manager
'manager'
But a default ``render()`` method implementation is not provided:
>>> base.render()
Traceback (most recent call last):
...
NotImplementedError: `render` method must be implemented by subclass.
If you have already an existing class that produces the HTML content in some
method, then the ``SimpleAttributeViewlet`` might be for you, since it can be
used to convert any class quickly into a viewlet:
>>> class FooViewlet(viewlet.SimpleAttributeViewlet):
... __page_attribute__ = 'foo'
...
... def foo(self):
... return 'output'
The `__page_attribute__` attribute provides the name of the function to call for
rendering.
>>> foo = FooViewlet('context', 'request', 'view', 'manager')
>>> foo.foo()
'output'
>>> foo.render()
'output'
If you specify `render` as the attribute an error is raised to prevent
infinite recursion:
>>> foo.__page_attribute__ = 'render'
>>> foo.render()
Traceback (most recent call last):
...
AttributeError: render
The same is true if the specified attribute does not exist:
>>> foo.__page_attribute__ = 'bar'
>>> foo.render()
Traceback (most recent call last):
...
AttributeError: 'FooViewlet' object has no attribute 'bar'
To create simple template-based viewlets you can use the
``SimpleViewletClass()`` function. This function is very similar to its view
equivalent and is used by the ZCML directives to create viewlets. The result
of this function call will be a fully functional viewlet class. Let's start by
simply specifying a template only:
>>> template = os.path.join(temp_dir, 'demoTemplate.pt')
>>> open(template, 'w').write('''
Now let's additionally specify a class that can provide additional features:
>>> class MyViewlet(object):
... myAttribute = 8
>>> Demo = viewlet.SimpleViewletClass(template, bases=(MyViewlet,))
>>> MyViewlet in Demo.__bases__
True
>>> Demo(content, request, view, manager).myAttribute
8
The final important feature is the ability to pass in further attributes to
the class:
>>> Demo = viewlet.SimpleViewletClass(
... template, attributes={'here': 'now', 'lucky': 3})
>>> demo = Demo(content, request, view, manager)
>>> demo.here
'now'
>>> demo.lucky
3
As for all views, they must provide a name that can also be passed to the
function:
>>> Demo = viewlet.SimpleViewletClass(template, name='demoViewlet')
>>> demo = Demo(content, request, view, manager)
>>> demo.__name__
'demoViewlet'
In addition to the the generic viewlet code above, the package comes with two
viewlet base classes and helper functions for inserting CSS and Javascript
links into HTML headers, since those two are so very common. I am only going
to demonstrate the helper functions here, since those demonstrations will
fully demonstrate the functionality of the base classes as well.
The viewlet will look up the resource it was given and tries to produce the
absolute URL for it:
>>> class JSResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/resource.js'
>>> zope.component.provideAdapter(
... JSResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='resource.js')
>>> JSViewlet = viewlet.JavaScriptViewlet('resource.js')
>>> print JSViewlet(content, request, view, manager).render().strip()
There is also a javascript viewlet base class which knows how to render more
then one javascript resource file:
>>> class JSSecondResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/second-resource.js'
>>> zope.component.provideAdapter(
... JSSecondResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='second-resource.js')
>>> JSBundleViewlet = viewlet.JavaScriptBundleViewlet(('resource.js',
... 'second-resource.js'))
>>> print JSBundleViewlet(content, request, view, manager).render().strip()
The same works for the CSS resource viewlet:
>>> class CSSResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/resource.css'
>>> zope.component.provideAdapter(
... CSSResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='resource.css')
>>> CSSViewlet = viewlet.CSSViewlet('resource.css')
>>> print CSSViewlet(content, request, view, manager).render().strip()
You can also change the media type and the rel attribute:
>>> CSSViewlet = viewlet.CSSViewlet('resource.css', media='print', rel='css')
>>> print CSSViewlet(content, request, view, manager).render().strip()
There is also a bundle viewlet for CSS links:
>>> class CSSPrintResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/print-resource.css'
>>> zope.component.provideAdapter(
... CSSPrintResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='print-resource.css')
>>> items = []
>>> items.append({'path':'resource.css', 'rel':'stylesheet', 'media':'all'})
>>> items.append({'path':'print-resource.css', 'media':'print'})
>>> CSSBundleViewlet = viewlet.CSSBundleViewlet(items)
>>> print CSSBundleViewlet(content, request, view, manager).render().strip()
A Complex Example
-----------------
The Data
~~~~~~~~
So far we have only demonstrated simple (maybe overly trivial) use cases of
the viewlet system. In the following example, we are going to develop a
generic contents view for files. The step is to create a file component:
>>> class IFile(zope.interface.Interface):
... data = zope.interface.Attribute('Data of file.')
>>> class File(object):
... zope.interface.implements(IFile)
... def __init__(self, data=''):
... self.__name__ = ''
... self.data = data
Since we want to also provide the size of a file, here a simple implementation
of the ``ISized`` interface:
>>> from zope import size
>>> class FileSized(object):
... zope.interface.implements(size.interfaces.ISized)
... zope.component.adapts(IFile)
...
... def __init__(self, file):
... self.file = file
...
... def sizeForSorting(self):
... return 'byte', len(self.file.data)
...
... def sizeForDisplay(self):
... return '%i bytes' %len(self.file.data)
>>> zope.component.provideAdapter(FileSized)
We also need a container to which we can add files:
>>> class Container(dict):
... def __setitem__(self, name, value):
... value.__name__ = name
... super(Container, self).__setitem__(name, value)
Here is some sample data:
>>> container = Container()
>>> container['test.txt'] = File('Hello World!')
>>> container['mypage.html'] = File('Hello World!')
>>> container['data.xml'] = File('Hello World!')
The View
~~~~~~~~
The contents view of the container should iterate through the container and
represent the files in a table:
>>> contentsTemplate = os.path.join(temp_dir, 'contents.pt')
>>> open(contentsTemplate, 'w').write('''
...
...
...
Contents
...
...
...
... ''')
>>> from zope.browserpage.simpleviewclass import SimpleViewClass
>>> Contents = SimpleViewClass(contentsTemplate, name='contents.html')
The Viewlet Manager
~~~~~~~~~~~~~~~~~~~
Now we have to write our own viewlet manager. In this case we cannot use the
default implementation, since the viewlets will be looked up for each
different item:
>>> shownColumns = []
>>> class ContentsViewletManager(object):
... zope.interface.implements(interfaces.IViewletManager)
... index = None
...
... def __init__(self, context, request, view):
... self.context = context
... self.request = request
... self.__parent__ = view
...
... def update(self):
... rows = []
... for name, value in self.context.items():
... rows.append(
... [zope.component.getMultiAdapter(
... (value, self.request, self.__parent__, self),
... interfaces.IViewlet, name=colname)
... for colname in shownColumns])
... [entry.update() for entry in rows[-1]]
... self.rows = rows
...
... def render(self, *args, **kw):
... return self.index(*args, **kw)
Now we need a template to produce the contents table:
>>> tableTemplate = os.path.join(temp_dir, 'table.pt')
>>> open(tableTemplate, 'w').write('''
...
...
...
...
...
...
...
... ''')
From the two pieces above, we can generate the final viewlet manager class and
register it (it's a bit tedious, I know):
>>> from zope.browserpage import ViewPageTemplateFile
>>> ContentsViewletManager = type(
... 'ContentsViewletManager', (ContentsViewletManager,),
... {'index': ViewPageTemplateFile(tableTemplate)})
>>> zope.component.provideAdapter(
... ContentsViewletManager,
... (Container, IDefaultBrowserLayer, zope.interface.Interface),
... interfaces.IViewletManager, name='contents')
Since we have not defined any viewlets yet, the table is totally empty:
>>> contents = Contents(container, request)
>>> print contents().strip()
Contents
The Viewlets and the Final Result
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Now let's create a first viewlet for the manager...
>>> class NameViewlet(object):
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
... self.context = context
...
... def update(self):
... pass
...
... def render(self):
... return self.context.__name__
and register it:
>>> zope.component.provideAdapter(
... NameViewlet,
... (IFile, IDefaultBrowserLayer,
... zope.interface.Interface, interfaces.IViewletManager),
... interfaces.IViewlet, name='name')
Note how you register the viewlet on ``IFile`` and not on the container. Now
we should be able to see the name for each file in the container:
>>> print contents().strip()
Contents
Waaa, nothing there! What happened? Well, we have to tell our user preferences
that we want to see the name as a column in the table:
>>> shownColumns = ['name']
>>> print contents().strip()
Contents
mypage.html
data.xml
test.txt
Let's now write a second viewlet that will display the size of the object for
us:
>>> class SizeViewlet(object):
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
... self.context = context
...
... def update(self):
... pass
...
... def render(self):
... return size.interfaces.ISized(self.context).sizeForDisplay()
>>> zope.component.provideAdapter(
... SizeViewlet,
... (IFile, IDefaultBrowserLayer,
... zope.interface.Interface, interfaces.IViewletManager),
... interfaces.IViewlet, name='size')
After we added it to the list of shown columns,
>>> shownColumns = ['name', 'size']
we can see an entry for it:
>>> print contents().strip()
Contents
mypage.html
38 bytes
data.xml
31 bytes
test.txt
12 bytes
If we switch the two columns around,
>>> shownColumns = ['size', 'name']
the result will be
>>> print contents().strip()
Contents
38 bytes
mypage.html
31 bytes
data.xml
12 bytes
test.txt
Supporting Sorting
~~~~~~~~~~~~~~~~~~
Oftentimes you also want to batch and sort the entries in a table. Since those
two features are not part of the view logic, they should be treated with
independent components. In this example, we are going to only implement
sorting using a simple utility:
>>> class ISorter(zope.interface.Interface):
...
... def sort(values):
... """Sort the values."""
>>> class SortByName(object):
... zope.interface.implements(ISorter)
...
... def sort(self, values):
... return sorted(values, lambda x, y: cmp(x.__name__, y.__name__))
>>> zope.component.provideUtility(SortByName(), name='name')
>>> class SortBySize(object):
... zope.interface.implements(ISorter)
...
... def sort(self, values):
... return sorted(
... values,
... lambda x, y: cmp(size.interfaces.ISized(x).sizeForSorting(),
... size.interfaces.ISized(y).sizeForSorting()))
>>> zope.component.provideUtility(SortBySize(), name='size')
Note that we decided to give the sorter utilities the same name as the
corresponding viewlet. This convention will make our implementation of the
viewlet manager much simpler:
>>> sortByColumn = ''
>>> class SortedContentsViewletManager(object):
... zope.interface.implements(interfaces.IViewletManager)
... index = None
...
... def __init__(self, context, request, view):
... self.context = context
... self.request = request
... self.__parent__ = view
...
... def update(self):
... values = self.context.values()
...
... if sortByColumn:
... sorter = zope.component.queryUtility(ISorter, sortByColumn)
... if sorter:
... values = sorter.sort(values)
...
... rows = []
... for value in values:
... rows.append(
... [zope.component.getMultiAdapter(
... (value, self.request, self.__parent__, self),
... interfaces.IViewlet, name=colname)
... for colname in shownColumns])
... [entry.update() for entry in rows[-1]]
... self.rows = rows
...
... def render(self, *args, **kw):
... return self.index(*args, **kw)
As you can see, the concern of sorting is cleanly separated from generating
the view code. In MVC terms that means that the controller (sort) is logically
separated from the view (viewlets). Let's now do the registration dance for
the new viewlet manager. We simply override the existing registration:
>>> SortedContentsViewletManager = type(
... 'SortedContentsViewletManager', (SortedContentsViewletManager,),
... {'index': ViewPageTemplateFile(tableTemplate)})
>>> zope.component.provideAdapter(
... SortedContentsViewletManager,
... (Container, IDefaultBrowserLayer, zope.interface.Interface),
... interfaces.IViewletManager, name='contents')
Finally we sort the contents by name:
>>> shownColumns = ['name', 'size']
>>> sortByColumn = 'name'
>>> print contents().strip()
Contents
data.xml
31 bytes
mypage.html
38 bytes
test.txt
12 bytes
Now let's sort by size:
>>> sortByColumn = 'size'
>>> print contents().strip()
Contents
test.txt
12 bytes
data.xml
31 bytes
mypage.html
38 bytes
That's it! As you can see, in a few steps we have built a pretty flexible
contents view with selectable columns and sorting. However, there is a lot of
room for extending this example:
- Table Header: The table header cell for each column should be a different
type of viewlet, but registered under the same name. The column header
viewlet also adapts the container not the item. The header column should
also be able to control the sorting.
- Batching: A simple implementation of batching should work very similar to
the sorting feature. Of course, efficient implementations should somehow
combine batching and sorting more effectively.
- Sorting in ascending and descending order: Currently, you can only sort from
the smallest to the highest value; however, this limitation is almost
superficial and can easily be removed by making the sorters a bit more
flexible.
- Further Columns: For a real application, you would want to implement other
columns, of course. You would also probably want some sort of fallback for
the case that a viewlet is not found for a particular container item and
column.
Cleanup
-------
>>> import shutil
>>> shutil.rmtree(temp_dir)
================================
The ``viewletManager`` Directive
================================
The ``viewletManager`` directive allows you to quickly register a new viewlet
manager without worrying about the details of the ``adapter``
directive. Before we can use the directives, we have to register their
handlers by executing the package's meta configuration:
>>> from zope.configuration import xmlconfig
>>> context = xmlconfig.string('''
...
...
...
... ''')
Now we can register a viewlet manager:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Let's make sure the directive has really issued a sensible adapter
registration; to do that, we create some dummy content, request and view
objects:
>>> import zope.interface
>>> class Content(object):
... zope.interface.implements(zope.interface.Interface)
>>> content = Content()
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> from zope.publisher.browser import BrowserView
>>> view = BrowserView(content, request)
Now let's lookup the manager. This particular registration is pretty boring:
>>> import zope.component
>>> from zope.viewlet import interfaces
>>> manager = zope.component.getMultiAdapter(
... (content, request, view),
... interfaces.IViewletManager, name='defaultmanager')
>>> manager
object ...>
>>> interfaces.IViewletManager.providedBy(manager)
True
>>> manager.template is None
True
>>> manager.update()
>>> manager.render()
u''
However, this registration is not very useful, since we did specify a specific
viewlet manager interface, a specific content interface, specific view or
specific layer. This means that all viewlets registered will be found.
The first step to effectively using the viewlet manager directive is to define
a special viewlet manager interface:
>>> class ILeftColumn(interfaces.IViewletManager):
... """Left column of my page."""
Now we can register register a manager providing this interface:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> manager = zope.component.getMultiAdapter(
... (content, request, view), ILeftColumn, name='leftcolumn')
>>> manager
object ...>
>>> ILeftColumn.providedBy(manager)
True
>>> manager.template is None
True
>>> manager.update()
>>> manager.render()
u''
Next let's see what happens, if we specify a template for the viewlet manager:
>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> leftColumnTemplate = os.path.join(temp_dir, 'leftcolumn.pt')
>>> open(leftColumnTemplate, 'w').write('''
...
Additionally you can specify a class that will serve as a base to the default
viewlet manager or be a viewlet manager in its own right. In our case we will
provide a custom implementation of the ``sort()`` method, which will sort by a
weight attribute in the viewlet:
>>> class WeightBasedSorting(object):
... def sort(self, viewlets):
... return sorted(viewlets,
... lambda x, y: cmp(x[1].weight, y[1].weight))
>>> context = xmlconfig.string('''
...
...
...
... ''' %leftColumnTemplate, context=context)
>>> manager = zope.component.getMultiAdapter(
... (content, request, view), ILeftColumn, name='leftcolumn')
>>> manager
object ...>
>>> manager.__class__.__bases__
(,
)
>>> ILeftColumn.providedBy(manager)
True
>>> manager.template
...>>
>>> manager.update()
>>> print manager.render().strip()
Finally, if a non-existent template is specified, an error is raised:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-7.8
ConfigurationError: ('No such file', '...foo.pt')
=========================
The ``viewlet`` Directive
=========================
Now that we have a viewlet manager, we have to register some viewlets for
it. The ``viewlet`` directive is similar to the ``viewletManager`` directive,
except that the viewlet is also registered for a particular manager interface,
as seen below:
>>> weatherTemplate = os.path.join(temp_dir, 'weather.pt')
>>> open(weatherTemplate, 'w').write('''
...
sunny
... ''')
>>> context = xmlconfig.string('''
...
...
...
... ''' % weatherTemplate, context=context)
If we look into the adapter registry, we will find the viewlet:
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='weather')
>>> viewlet.render().strip()
u'
sunny
'
>>> viewlet.extra_string_attributes
u'can be specified'
The manager now also gives us the output of the one and only viewlet:
>>> manager.update()
>>> print manager.render().strip()
sunny
Let's now ensure that we can also specify a viewlet class:
>>> class Weather(object):
... weight = 0
>>> context = xmlconfig.string('''
...
...
...
... ''' % weatherTemplate, context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='weather2')
>>> viewlet().strip()
u'
sunny
'
Okay, so the template-driven cases work. But just specifying a class should
also work:
>>> class Sport(object):
... weight = 0
... def __call__(self):
... return u'Red Sox vs. White Sox'
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet, name='sport')
>>> viewlet()
u'Red Sox vs. White Sox'
It should also be possible to specify an alternative attribute of the class to
be rendered upon calling the viewlet:
>>> class Stock(object):
... weight = 0
... def getStockTicker(self):
... return u'SRC $5.19'
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='stock')
>>> viewlet.render()
u'SRC $5.19'
A final feature the ``viewlet`` directive is that it supports the
specification of any number of keyword arguments:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='stock2')
>>> viewlet.weight
u'8'
Error Scenarios
---------------
Neither the class or template have been specified:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-7.8
ConfigurationError: Must specify a class or template
The specified attribute is not ``__call__``, but also a template has been
specified:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-9.8
ConfigurationError: Attribute and template cannot be used together.
Now, we are not specifying a template, but a class that does not have the
specified attribute:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-9.8
ConfigurationError: The provided class doesn't have the specified attribute
Cleanup
-------
>>> import shutil
>>> shutil.rmtree(temp_dir)
=======
CHANGES
=======
3.7.2 (2010-05-25)
------------------
- Fixed unit tests broken under Python 2.4 by the switch to the standard
library ``doctest`` module.
3.7.1 (2010-04-30)
------------------
- Removed use of 'zope.testing.doctest' in favor of stdlib's 'doctest.
- Fixed dubious quoting in metadirectives.py. Closes
https://bugs.launchpad.net/zope2/+bug/143774.
3.7.0 (2009-12-22)
------------------
- Depend on zope.browserpage in favor of zope.app.pagetemplate.
3.6.1 (2009-08-29)
------------------
- Fixed unit tests in README.txt.
3.6.0 (2009-08-02)
------------------
- Optimize the the script tag for the JS viewlet. This makes YSlow happy.
- Remove ZCML slugs and old zpkg-related files.
- Drop all testing dependncies except ``zope.testing``.
3.5.0 (2009-01-26)
------------------
- Removed the dependency on `zope.app.publisher` by moving four simple helper
functions into this package and making the interface for describing the
ZCML content provider directive explicit.
- Typo fix in CSSViewlet docstring.
3.4.2 (2008-01-24)
------------------
- Re-release of 3.4.1 because of brown bag release.
3.4.1 (2008-01-21)
------------------
- bugfix, implemented missing __contains__ method in IViewletManager
- implemented additional viewlet managers offering weight ordered sorting
- implemented additional viewlet managers offering conditional filtering
3.4.1a (2007-4-22)
------------------
- bugfix, added a missing ',' behind zope.i18nmessageid.
- recreated the README.txt removing everything except for the overview.
3.4.0 (2007-10-10)
------------------
- Initial release independent of the main Zope tree.
Keywords: zope web html ui viewlet pattern
Platform: UNKNOWN
Classifier: Development Status :: 5 - Production/Stable
Classifier: Environment :: Web Environment
Classifier: Intended Audience :: Developers
Classifier: License :: OSI Approved :: Zope Public License
Classifier: Programming Language :: Python
Classifier: Natural Language :: English
Classifier: Operating System :: OS Independent
Classifier: Topic :: Internet :: WWW/HTTP
Classifier: Framework :: Zope3
zope.viewlet-3.7.2/src/zope.viewlet.egg-info/not-zip-safe 0000644 0001750 0001750 00000000001 11376754212 023234 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/ 0000755 0001750 0001750 00000000000 11376754277 015651 5 ustar tseaver tseaver zope.viewlet-3.7.2/src/zope/viewlet/ 0000755 0001750 0001750 00000000000 11376754277 017330 5 ustar tseaver tseaver zope.viewlet-3.7.2/src/zope/viewlet/manager.py 0000644 0001750 0001750 00000014607 11376754171 021315 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Content Provider Manager implementation
$Id: manager.py 112059 2010-05-05 19:40:35Z tseaver $
"""
__docformat__ = 'restructuredtext'
import zope.component
import zope.interface
import zope.security
import zope.event
from zope.browserpage import ViewPageTemplateFile
from zope.viewlet import interfaces
from zope.location.interfaces import ILocation
from zope.contentprovider.interfaces import BeforeUpdateEvent
class ViewletManagerBase(object):
"""The Viewlet Manager Base
A generic manager class which can be instantiated
"""
zope.interface.implements(interfaces.IViewletManager)
template = None
def __init__(self, context, request, view):
self.__updated = False
self.__parent__ = view
self.context = context
self.request = request
def __getitem__(self, name):
"""See zope.interface.common.mapping.IReadMapping"""
# Find the viewlet
viewlet = zope.component.queryMultiAdapter(
(self.context, self.request, self.__parent__, self),
interfaces.IViewlet, name=name)
# If the viewlet was not found, then raise a lookup error
if viewlet is None:
raise zope.component.interfaces.ComponentLookupError(
'No provider with name `%s` found.' %name)
# If the viewlet cannot be accessed, then raise an
# unauthorized error
if not zope.security.canAccess(viewlet, 'render'):
raise zope.security.interfaces.Unauthorized(
'You are not authorized to access the provider '
'called `%s`.' %name)
# Return the viewlet.
return viewlet
def get(self, name, default=None):
"""See zope.interface.common.mapping.IReadMapping"""
try:
return self[name]
except (zope.component.interfaces.ComponentLookupError,
zope.security.interfaces.Unauthorized):
return default
def __contains__(self, name):
"""See zope.interface.common.mapping.IReadMapping"""
return bool(self.get(name, False))
def filter(self, viewlets):
"""Sort out all content providers
``viewlets`` is a list of tuples of the form (name, viewlet).
"""
# Only return viewlets accessible to the principal
return [(name, viewlet) for name, viewlet in viewlets
if zope.security.canAccess(viewlet, 'render')]
def sort(self, viewlets):
"""Sort the viewlets.
``viewlets`` is a list of tuples of the form (name, viewlet).
"""
# By default, use the standard Python way of doing sorting.
return sorted(viewlets, lambda x, y: cmp(x[1], y[1]))
def update(self):
"""See zope.contentprovider.interfaces.IContentProvider"""
self.__updated = True
# Find all content providers for the region
viewlets = zope.component.getAdapters(
(self.context, self.request, self.__parent__, self),
interfaces.IViewlet)
viewlets = self.filter(viewlets)
viewlets = self.sort(viewlets)
# Just use the viewlets from now on
self.viewlets=[]
for name, viewlet in viewlets:
if ILocation.providedBy(viewlet):
viewlet.__name__ = name
self.viewlets.append(viewlet)
self._updateViewlets()
def _updateViewlets(self):
"""Calls update on all viewlets and fires events"""
for viewlet in self.viewlets:
zope.event.notify(BeforeUpdateEvent(viewlet, self.request))
viewlet.update()
def render(self):
"""See zope.contentprovider.interfaces.IContentProvider"""
# Now render the view
if self.template:
return self.template(viewlets=self.viewlets)
else:
return u'\n'.join([viewlet.render() for viewlet in self.viewlets])
def ViewletManager(name, interface, template=None, bases=()):
attrDict = {'__name__' : name}
if template is not None:
attrDict['template'] = ViewPageTemplateFile(template)
if ViewletManagerBase not in bases:
# Make sure that we do not get a default viewlet manager mixin, if the
# provided base is already a full viewlet manager implementation.
if not (len(bases) == 1 and
interfaces.IViewletManager.implementedBy(bases[0])):
bases = bases + (ViewletManagerBase,)
ViewletManager = type(
'' % interface.getName(), bases, attrDict)
zope.interface.classImplements(ViewletManager, interface)
return ViewletManager
def getWeight((name, viewlet)):
try:
return int(viewlet.weight)
except AttributeError:
return 0
class WeightOrderedViewletManager(ViewletManagerBase):
"""Weight ordered viewlet managers."""
def sort(self, viewlets):
return sorted(viewlets, key=getWeight)
def render(self):
"""See zope.contentprovider.interfaces.IContentProvider"""
# do not render a manager template if no viewlets are avaiable
if not self.viewlets:
return u''
elif self.template:
return self.template(viewlets=self.viewlets)
else:
return u'\n'.join([viewlet.render() for viewlet in self.viewlets])
def isAvailable(viewlet):
try:
return zope.security.canAccess(viewlet, 'render') and viewlet.available
except AttributeError:
return True
class ConditionalViewletManager(WeightOrderedViewletManager):
"""Conditional weight ordered viewlet managers."""
def filter(self, viewlets):
"""Sort out all viewlets which are explicit not available
``viewlets`` is a list of tuples of the form (name, viewlet).
"""
return [(name, viewlet) for name, viewlet in viewlets
if isAvailable(viewlet)]
zope.viewlet-3.7.2/src/zope/viewlet/css_bundle_viewlet.pt 0000644 0001750 0001750 00000000365 11376754171 023552 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/viewlet/communicating-viewlets.txt 0000644 0001750 0001750 00000007040 11376754171 024560 0 ustar tseaver tseaver ==============================================
A technique for communication between viewlets
==============================================
Sometimes one wants viewlets to communicate with each other to supplement a
more generic viewlet's behaviour with another viewlet. One example would be a
viewlet that contains a search form created by a library such as z3c.form,
plus a second viewlet that provides a list of search results.
This is very simple to accomplish with zope.viewlet but has turned out not to
be obvious, so here is an explicit example. It is not written as a doc test
since it uses z3c.form which should not become a dependency of zope.viewlet.
The viewlets
============
For the purpose of this example, we simulate a search form. Our search results
are simply the characters of the search term and are stored on the viewlet as
an attribute:
class ISearchForm(zope.interface.Interface):
searchterm = zope.schema.TextLine(title=u"Search term")
class SearchForm(z3c.form.form.Form):
ignoreContext = True
fields = z3c.form.field.Fields(ISearchForm)
results = ""
@z3c.form.button.buttonAndHandler(u"Search")
def search(self, action):
data, errors = self.extractData()
self.results = list(data["searchterm"])
(Notice that this example is minimized to point out communication between
viewlets, and no care is taken to handle the form itself in the best way
possible. In particular, one will probably want to make sure that the actual
search is not performed more than once, which may happen with the above code.)
The result list viewlet needs to display the results stored on the search
form. Therefore, the result list viewlet needs to access that viewlet, which
is probably the only tricky part (if there is any at all) in this example:
Since viewlets know their viewlet manager which lets viewlets be looked up by
ID, it is all a matter of the result list viewlet knowing the ID of the search
form.
We'll store the search form viewlet's ID as an attribute of the result list
viewlet. Let's hard-code the ID for a start, then the result list looks like
this:
class ResultList(zope.viewlet.viewlet.ViewletBase):
searchform_id = "searchform"
def update(self):
super(ResultList, self).update()
searchform = self.manager[self.searchform_id]
searchform.update()
self.results = searchform.results
def render(self):
return "
%s
" % "\n".join(u"
%s
" % x
for x in self.results)
Registering the viewlets
========================
As long as we treat the ID of the search form as hard-coded, we have to use
the correct name when registering the two viewlets:
Making the ID of the search form more flexible now doesn't even require
changing any code: the viewlet directive may be passed arbitrary attributes
which will be available as attributes of the ResultList objects. The attribute
that holds our search form's ID is searchform_id, so we might register the
viewlets like this:
zope.viewlet-3.7.2/src/zope/viewlet/interfaces.py 0000644 0001750 0001750 00000004064 11376754171 022022 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Viewlet interfaces
$Id: interfaces.py 112059 2010-05-05 19:40:35Z tseaver $
"""
__docformat__ = 'restructuredtext'
import zope.interface
from zope.contentprovider.interfaces import IContentProvider
from zope.i18nmessageid import MessageFactory
_ = MessageFactory('zope')
class IViewlet(IContentProvider):
"""A content provider that is managed by another content provider, known
as viewlet manager.
Note that you *cannot* call viewlets directly as a provider, i.e. through
the TALES ``provider`` expression, since it always has to know its manager.
"""
manager = zope.interface.Attribute(
"""The Viewlet Manager
The viewlet manager for which the viewlet is registered. The viewlet
manager will contain any additional data that was provided by the
view, for example the TAL namespace attributes.
""")
class IViewletManager(IContentProvider,
zope.interface.common.mapping.IReadMapping):
"""A component that provides access to the content providers.
The viewlet manager's resposibilities are:
(1) Aggregation of all viewlets registered for the manager.
(2) Apply a set of filters to determine the availability of the
viewlets.
(3) Sort the viewlets based on some implemented policy.
(4) Provide an environment in which the viewlets are rendered.
(5) Render itself containing the HTML content of the viewlets.
"""
zope.viewlet-3.7.2/src/zope/viewlet/meta.zcml 0000644 0001750 0001750 00000000762 11376754171 021143 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/viewlet/metaconfigure.py 0000644 0001750 0001750 00000020444 11376754171 022527 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Viewlet metadconfigure
$Id: metaconfigure.py 112059 2010-05-05 19:40:35Z tseaver $
"""
__docformat__ = 'restructuredtext'
import os
from zope.security import checker
from zope.configuration.exceptions import ConfigurationError
from zope.interface import Interface, classImplements
from zope.publisher.interfaces.browser import IDefaultBrowserLayer
from zope.publisher.interfaces.browser import IBrowserPublisher
from zope.publisher.interfaces.browser import IBrowserView
from zope.component import zcml
from zope.component.interface import provideInterface
from zope.viewlet import viewlet, manager, interfaces
def viewletManagerDirective(
_context, name, permission,
for_=Interface, layer=IDefaultBrowserLayer, view=IBrowserView,
provides=interfaces.IViewletManager, class_=None, template=None,
allowed_interface=None, allowed_attributes=None):
# A list of attributes available under the provided permission
required = {}
# Get the permission; mainly to correctly handle CheckerPublic.
permission = _handle_permission(_context, permission)
# If class is not given we use the basic viewlet manager.
if class_ is None:
class_ = manager.ViewletManagerBase
# Make sure that the template exists and that all low-level API methods
# have the right permission.
if template:
template = os.path.abspath(str(_context.path(template)))
if not os.path.isfile(template):
raise ConfigurationError("No such file", template)
required['__getitem__'] = permission
# Create a new class based on the template and class.
new_class = manager.ViewletManager(
name, provides, template=template, bases=(class_, ))
else:
# Create a new class based on the class.
new_class = manager.ViewletManager(name, provides, bases=(class_, ))
# Register some generic attributes with the security dictionary
for attr_name in ('browserDefault', 'update', 'render', 'publishTraverse'):
required[attr_name] = permission
# Register the ``provides`` interface and register fields in the security
# dictionary
_handle_allowed_interface(
_context, (provides,), permission, required)
# Register the allowed interface and add the field's security entries
_handle_allowed_interface(
_context, allowed_interface, permission, required)
# Register single allowed attributes in the security dictionary
_handle_allowed_attributes(
_context, allowed_attributes, permission, required)
# Register interfaces
_handle_for(_context, for_)
zcml.interface(_context, view)
# Create a checker for the viewlet manager
checker.defineChecker(new_class, checker.Checker(required))
# register a viewlet manager
_context.action(
discriminator = ('viewletManager', for_, layer, view, name),
callable = zcml.handler,
args = ('registerAdapter',
new_class, (for_, layer, view), provides, name,
_context.info),)
def viewletDirective(
_context, name, permission,
for_=Interface, layer=IDefaultBrowserLayer, view=IBrowserView,
manager=interfaces.IViewletManager, class_=None, template=None,
attribute='render', allowed_interface=None, allowed_attributes=None,
**kwargs):
# Security map dictionary
required = {}
# Get the permission; mainly to correctly handle CheckerPublic.
permission = _handle_permission(_context, permission)
# Either the class or template must be specified.
if not (class_ or template):
raise ConfigurationError("Must specify a class or template")
# Make sure that all the non-default attribute specifications are correct.
if attribute != 'render':
if template:
raise ConfigurationError(
"Attribute and template cannot be used together.")
# Note: The previous logic forbids this condition to evere occur.
if not class_:
raise ConfigurationError(
"A class must be provided if attribute is used")
# Make sure that the template exists and that all low-level API methods
# have the right permission.
if template:
template = os.path.abspath(str(_context.path(template)))
if not os.path.isfile(template):
raise ConfigurationError("No such file", template)
required['__getitem__'] = permission
# Make sure the has the right form, if specified.
if class_:
if attribute != 'render':
if not hasattr(class_, attribute):
raise ConfigurationError(
"The provided class doesn't have the specified attribute "
)
if template:
# Create a new class for the viewlet template and class.
new_class = viewlet.SimpleViewletClass(
template, bases=(class_, ), attributes=kwargs, name=name)
else:
if not hasattr(class_, 'browserDefault'):
cdict = {'browserDefault':
lambda self, request: (getattr(self, attribute), ())}
else:
cdict = {}
cdict['__name__'] = name
cdict['__page_attribute__'] = attribute
cdict.update(kwargs)
new_class = type(class_.__name__,
(class_, viewlet.SimpleAttributeViewlet), cdict)
if hasattr(class_, '__implements__'):
classImplements(new_class, IBrowserPublisher)
else:
# Create a new class for the viewlet template alone.
new_class = viewlet.SimpleViewletClass(template, name=name,
attributes=kwargs)
# Set up permission mapping for various accessible attributes
_handle_allowed_interface(
_context, allowed_interface, permission, required)
_handle_allowed_attributes(
_context, allowed_attributes, permission, required)
_handle_allowed_attributes(
_context, kwargs.keys(), permission, required)
_handle_allowed_attributes(
_context,
(attribute, 'browserDefault', 'update', 'render', 'publishTraverse'),
permission, required)
# Register the interfaces.
_handle_for(_context, for_)
zcml.interface(_context, view)
# Create the security checker for the new class
checker.defineChecker(new_class, checker.Checker(required))
# register viewlet
_context.action(
discriminator = ('viewlet', for_, layer, view, manager, name),
callable = zcml.handler,
args = ('registerAdapter',
new_class, (for_, layer, view, manager), interfaces.IViewlet,
name, _context.info),)
def _handle_permission(_context, permission):
if permission == 'zope.Public':
permission = checker.CheckerPublic
return permission
def _handle_allowed_interface(_context, allowed_interface, permission,
required):
# Allow access for all names defined by named interfaces
if allowed_interface:
for i in allowed_interface:
_context.action(
discriminator = None,
callable = provideInterface,
args = (None, i)
)
for name in i:
required[name] = permission
def _handle_allowed_attributes(_context, allowed_attributes, permission,
required):
# Allow access for all named attributes
if allowed_attributes:
for name in allowed_attributes:
required[name] = permission
def _handle_for(_context, for_):
if for_ is not None:
_context.action(
discriminator = None,
callable = provideInterface,
args = ('', for_)
)
zope.viewlet-3.7.2/src/zope/viewlet/metadirectives.py 0000644 0001750 0001750 00000014211 11376754171 022702 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Viewlet metadirective
$Id: metadirectives.py 112059 2010-05-05 19:40:35Z tseaver $
"""
__docformat__ = 'restructuredtext'
import zope.configuration.fields
import zope.schema
from zope.publisher.interfaces import browser
from zope.security.zcml import Permission
from zope.i18nmessageid import MessageFactory
from zope.interface import Interface
_ = MessageFactory('zope')
from zope.viewlet import interfaces
class IContentProvider(Interface):
"""A directive to register a simple content provider.
Content providers are registered by their context (`for` attribute), the
request (`layer` attribute) and the view (`view` attribute). They also
must provide a name, so that they can be found using the TALES
``provider`` namespace. Other than that, content providers are just like
any other views.
"""
view = zope.configuration.fields.GlobalObject(
title=_("The view the content provider is registered for."),
description=_("The view can either be an interface or a class. By "
"default the provider is registered for all views, "
"the most common case."),
required=False,
default=browser.IBrowserView)
name = zope.schema.TextLine(
title=_("The name of the content provider."),
description=_("The name of the content provider is used in the TALES "
"``provider`` namespace to look up the content "
"provider."),
required=True)
for_ = zope.configuration.fields.GlobalObject(
title=u"The interface or class this view is for.",
required=False
)
permission = Permission(
title=u"Permission",
description=u"The permission needed to use the view.",
required=True
)
class_ = zope.configuration.fields.GlobalObject(
title=_("Class"),
description=_("A class that provides attributes used by the view."),
required=False,
)
layer = zope.configuration.fields.GlobalInterface(
title=_("The layer the view is in."),
description=_("""
A skin is composed of layers. It is common to put skin
specific views in a layer named after the skin. If the 'layer'
attribute is not supplied, it defaults to 'default'."""),
required=False,
)
allowed_interface = zope.configuration.fields.Tokens(
title=_("Interface that is also allowed if user has permission."),
description=_("""
By default, 'permission' only applies to viewing the view and
any possible sub views. By specifying this attribute, you can
make the permission also apply to everything described in the
supplied interface.
Multiple interfaces can be provided, separated by
whitespace."""),
required=False,
value_type=zope.configuration.fields.GlobalInterface(),
)
allowed_attributes = zope.configuration.fields.Tokens(
title=_("View attributes that are also allowed if the user"
" has permission."),
description=_("""
By default, 'permission' only applies to viewing the view and
any possible sub views. By specifying 'allowed_attributes',
you can make the permission also apply to the extra attributes
on the view object."""),
required=False,
value_type=zope.configuration.fields.PythonIdentifier(),
)
class ITemplatedContentProvider(IContentProvider):
"""A directive for registering a content provider that uses a page
template to provide its content."""
template = zope.configuration.fields.Path(
title=_("Content-generating template."),
description=_("Refers to a file containing a page template (should "
"end in extension ``.pt`` or ``.html``)."),
required=False)
class IViewletManagerDirective(ITemplatedContentProvider):
"""A directive to register a new viewlet manager.
Viewlet manager registrations are very similar to content provider
registrations, since they are just a simple extension of content
providers. However, viewlet managers commonly have a specific provided
interface, which is used to discriminate the viewlets they are providing.
"""
provides = zope.configuration.fields.GlobalInterface(
title=_("The interface this viewlet manager provides."),
description=_("A viewlet manager can provide an interface, which "
"is used to lookup its contained viewlets."),
required=False,
default=interfaces.IViewletManager,
)
class IViewletDirective(ITemplatedContentProvider):
"""A directive to register a new viewlet.
Viewlets are content providers that can only be displayed inside a viewlet
manager. Thus they are additionally discriminated by the manager. Viewlets
can rely on the specified viewlet manager interface to provide their
content.
The viewlet directive also supports an undefined set of keyword arguments
that are set as attributes on the viewlet after creation. Those attributes
can then be used to implement sorting and filtering, for example.
"""
manager = zope.configuration.fields.GlobalObject(
title=_("view"),
description=u"The interface of the view this viewlet is for. "
u"(default IBrowserView)",
required=False,
default=interfaces.IViewletManager)
# Arbitrary keys and values are allowed to be passed to the viewlet.
IViewletDirective.setTaggedValue('keyword_arguments', True)
zope.viewlet-3.7.2/src/zope/viewlet/javascript_viewlet.pt 0000644 0001750 0001750 00000000150 11376754171 023567 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/viewlet/README.txt 0000644 0001750 0001750 00000106524 11376754171 021027 0 ustar tseaver tseaver =============================
Viewlets and Viewlet Managers
=============================
Let's start with some motivation. Using content providers allows us to insert
one piece of HTML content. In most Web development, however, you are often
interested in defining some sort of region and then allow developers to
register content for those regions.
>>> from zope.viewlet import interfaces
Design Notes
------------
As mentioned above, besides inserting snippets of HTML at places, we more
frequently want to define a region in our page and allow specialized content
providers to be inserted based on configuration. Those specialized content
providers are known as viewlets and are only available inside viewlet
managers, which are just a more complex example of content providers.
Unfortunately, the Java world does not implement this layer separately. The
viewlet manager is most similar to a Java "channel", but we decided against
using this name, since it is very generic and not very meaningful. The viewlet
has no Java counterpart, since Java does not implement content providers using
a component architecture and thus does not register content providers
specifically for viewlet managers, which I believe makes the Java
implementation less useful as a generic concept. In fact, the main design
goal in the Java world is the implementation of reusable and sharable
portlets. The scope for Zope 3 is larger, since we want to provide a generic
framework for building pluggable user interfaces.
The Viewlet Manager
-------------------
In this implementation of viewlets, those regions are just content providers
called viewlet managers that manage a special type of content providers known
as viewlets. Every viewlet manager handles the viewlets registered for it:
>>> class ILeftColumn(interfaces.IViewletManager):
... """Viewlet manager located in the left column."""
You can then create a viewlet manager using this interface now:
>>> from zope.viewlet import manager
>>> LeftColumn = manager.ViewletManager('left', ILeftColumn)
Now we have to instantiate it:
>>> import zope.interface
>>> class Content(object):
... zope.interface.implements(zope.interface.Interface)
>>> content = Content()
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> from zope.publisher.interfaces.browser import IBrowserView
>>> class View(object):
... zope.interface.implements(IBrowserView)
... def __init__(self, context, request):
... pass
>>> view = View(content, request)
>>> leftColumn = LeftColumn(content, request, view)
So initially nothing gets rendered:
>>> leftColumn.update()
>>> leftColumn.render()
u''
But now we register some viewlets for the manager
>>> import zope.component
>>> from zope.publisher.interfaces.browser import IDefaultBrowserLayer
>>> class WeatherBox(object):
... zope.interface.implements(interfaces.IViewlet)
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
...
... def update(self):
... pass
...
... def render(self):
... return u'
'
>>> defineChecker(SportBox, viewletChecker)
>>> zope.component.provideAdapter(
... SportBox,
... (zope.interface.Interface, IDefaultBrowserLayer,
... IBrowserView, ILeftColumn),
... interfaces.IViewlet, name='sport')
and thus the left column is filled. Note that also events get fired
before viewlets are updated. We register a simple handler to
demonstrate this behaviour.
>>> from zope.contentprovider.interfaces import IBeforeUpdateEvent
>>> events = []
>>> def handler(ev):
... events.append(ev)
>>> zope.component.provideHandler(handler, (IBeforeUpdateEvent,))
>>> leftColumn.update()
>>> [(ev, ev.object.__class__.__name__) for ev in events]
[(, 'SportBox'),
(, 'WeatherBox')]
>>> print leftColumn.render()
Patriots (23) : Steelers (7)
It is sunny today!
But this is of course pretty lame, since there is no way of specifying how the
viewlets are put together. But we have a solution. The second argument of the
``ViewletManager()`` function is a template in which we can specify how the
viewlets are put together:
>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> leftColTemplate = os.path.join(temp_dir, 'leftCol.pt')
>>> open(leftColTemplate, 'w').write('''
...
...
...
... ''')
>>> LeftColumn = manager.ViewletManager('left', ILeftColumn,
... template=leftColTemplate)
>>> leftColumn = LeftColumn(content, request, view)
TODO: Fix this silly thing; viewlets should be directly available.
As you can see, the viewlet manager provides a global ``options/viewlets``
variable that is an iterable of all the available viewlets in the correct
order:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
It is sunny today!
If a viewlet provides ILocation the ``__name__`` attribute of the
viewlet is set to the name under which the viewlet is registered.
>>> [getattr(viewlet, '__name__', None) for viewlet in leftColumn.viewlets]
[u'sport', None]
You can also lookup the viewlets directly for management purposes:
>>> leftColumn['weather']
>>> leftColumn.get('weather')
The viewlet manager also provides the __contains__ method defined in
IReadMapping:
>>> 'weather' in leftColumn
True
>>> 'unknown' in leftColumn
False
If the viewlet is not found, then the expected behavior is provided:
>>> leftColumn['stock']
Traceback (most recent call last):
...
ComponentLookupError: No provider with name `stock` found.
>>> leftColumn.get('stock') is None
True
Customizing the default Viewlet Manager
---------------------------------------
One important feature of any viewlet manager is to be able to filter and sort
the viewlets it is displaying. The default viewlet manager that we have been
using in the tests above, supports filtering by access availability and
sorting via the viewlet's ``__cmp__()`` method (default). You can easily
override this default policy by providing a base viewlet manager class.
In our case we will manage the viewlets using a global list:
>>> shown = ['weather', 'sport']
The viewlet manager base class now uses this list:
>>> class ListViewletManager(object):
...
... def filter(self, viewlets):
... viewlets = super(ListViewletManager, self).filter(viewlets)
... return [(name, viewlet)
... for name, viewlet in viewlets
... if name in shown]
...
... def sort(self, viewlets):
... viewlets = dict(viewlets)
... return [(name, viewlets[name]) for name in shown]
Let's now create a new viewlet manager:
>>> LeftColumn = manager.ViewletManager(
... 'left', ILeftColumn, bases=(ListViewletManager,),
... template=leftColTemplate)
>>> leftColumn = LeftColumn(content, request, view)
So we get the weather box first and the sport box second:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
It is sunny today!
Patriots (23) : Steelers (7)
Now let's change the order...
>>> shown.reverse()
and the order should switch as well:
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
It is sunny today!
Of course, we also can remove a shown viewlet:
>>> weather = shown.pop()
>>> leftColumn.update()
>>> print leftColumn.render().strip()
Patriots (23) : Steelers (7)
WeightOrderedViewletManager
---------------------------
The weight ordered viewlet manager offers ordering viewlets by a additional
weight argument. Viewlets which doesn't provide a weight attribute will get
a weight of 0 (zero).
Let's define a new column:
>>> class IWeightedColumn(interfaces.IViewletManager):
... """Column with weighted viewlet manager."""
First register a template for the weight ordered viewlet manager:
>>> weightedColTemplate = os.path.join(temp_dir, 'weightedColTemplate.pt')
>>> open(weightedColTemplate, 'w').write('''
...
...
...
... ''')
And create a new weight ordered viewlet manager:
>>> from zope.viewlet.manager import WeightOrderedViewletManager
>>> WeightedColumn = manager.ViewletManager(
... 'left', IWeightedColumn, bases=(WeightOrderedViewletManager,),
... template=weightedColTemplate)
>>> weightedColumn = WeightedColumn(content, request, view)
Let's create some viewlets:
>>> from zope.viewlet import viewlet
>>> class FirstViewlet(viewlet.ViewletBase):
...
... weight = 1
...
... def render(self):
... return u'
ConditionalViewletManager
-------------------------
The conditional ordered viewlet manager offers ordering viewlets by a
additional weight argument and filters by the available attribute if a
supported by the viewlet. Viewlets which doesn't provide a available attribute
will not get skipped. The default weight value for viewlets which doesn't
provide a weight attribute is 0 (zero).
Let's define a new column:
>>> class IConditionalColumn(interfaces.IViewletManager):
... """Column with weighted viewlet manager."""
First register a template for the weight ordered viewlet manager:
>>> conditionalColTemplate = os.path.join(temp_dir,
... 'conditionalColTemplate.pt')
>>> open(conditionalColTemplate, 'w').write('''
...
...
...
... ''')
And create a new conditional viewlet manager:
>>> from zope.viewlet.manager import ConditionalViewletManager
>>> ConditionalColumn = manager.ViewletManager(
... 'left', IConditionalColumn, bases=(ConditionalViewletManager,),
... template=conditionalColTemplate)
>>> conditionalColumn = ConditionalColumn(content, request, view)
Let's create some viewlets. We also use the previous viewlets supporting no
weight and or no available attribute:
>>> from zope.viewlet import viewlet
>>> class AvailableViewlet(viewlet.ViewletBase):
...
... weight = 4
...
... available = True
...
... def render(self):
... return u'
Viewlet Base Classes
--------------------
To make the creation of viewlets simpler, a set of useful base classes and
helper functions are provided.
The first class is a base class that simply defines the constructor:
>>> base = viewlet.ViewletBase('context', 'request', 'view', 'manager')
>>> base.context
'context'
>>> base.request
'request'
>>> base.__parent__
'view'
>>> base.manager
'manager'
But a default ``render()`` method implementation is not provided:
>>> base.render()
Traceback (most recent call last):
...
NotImplementedError: `render` method must be implemented by subclass.
If you have already an existing class that produces the HTML content in some
method, then the ``SimpleAttributeViewlet`` might be for you, since it can be
used to convert any class quickly into a viewlet:
>>> class FooViewlet(viewlet.SimpleAttributeViewlet):
... __page_attribute__ = 'foo'
...
... def foo(self):
... return 'output'
The `__page_attribute__` attribute provides the name of the function to call for
rendering.
>>> foo = FooViewlet('context', 'request', 'view', 'manager')
>>> foo.foo()
'output'
>>> foo.render()
'output'
If you specify `render` as the attribute an error is raised to prevent
infinite recursion:
>>> foo.__page_attribute__ = 'render'
>>> foo.render()
Traceback (most recent call last):
...
AttributeError: render
The same is true if the specified attribute does not exist:
>>> foo.__page_attribute__ = 'bar'
>>> foo.render()
Traceback (most recent call last):
...
AttributeError: 'FooViewlet' object has no attribute 'bar'
To create simple template-based viewlets you can use the
``SimpleViewletClass()`` function. This function is very similar to its view
equivalent and is used by the ZCML directives to create viewlets. The result
of this function call will be a fully functional viewlet class. Let's start by
simply specifying a template only:
>>> template = os.path.join(temp_dir, 'demoTemplate.pt')
>>> open(template, 'w').write('''
Now let's additionally specify a class that can provide additional features:
>>> class MyViewlet(object):
... myAttribute = 8
>>> Demo = viewlet.SimpleViewletClass(template, bases=(MyViewlet,))
>>> MyViewlet in Demo.__bases__
True
>>> Demo(content, request, view, manager).myAttribute
8
The final important feature is the ability to pass in further attributes to
the class:
>>> Demo = viewlet.SimpleViewletClass(
... template, attributes={'here': 'now', 'lucky': 3})
>>> demo = Demo(content, request, view, manager)
>>> demo.here
'now'
>>> demo.lucky
3
As for all views, they must provide a name that can also be passed to the
function:
>>> Demo = viewlet.SimpleViewletClass(template, name='demoViewlet')
>>> demo = Demo(content, request, view, manager)
>>> demo.__name__
'demoViewlet'
In addition to the the generic viewlet code above, the package comes with two
viewlet base classes and helper functions for inserting CSS and Javascript
links into HTML headers, since those two are so very common. I am only going
to demonstrate the helper functions here, since those demonstrations will
fully demonstrate the functionality of the base classes as well.
The viewlet will look up the resource it was given and tries to produce the
absolute URL for it:
>>> class JSResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/resource.js'
>>> zope.component.provideAdapter(
... JSResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='resource.js')
>>> JSViewlet = viewlet.JavaScriptViewlet('resource.js')
>>> print JSViewlet(content, request, view, manager).render().strip()
There is also a javascript viewlet base class which knows how to render more
then one javascript resource file:
>>> class JSSecondResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/second-resource.js'
>>> zope.component.provideAdapter(
... JSSecondResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='second-resource.js')
>>> JSBundleViewlet = viewlet.JavaScriptBundleViewlet(('resource.js',
... 'second-resource.js'))
>>> print JSBundleViewlet(content, request, view, manager).render().strip()
The same works for the CSS resource viewlet:
>>> class CSSResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/resource.css'
>>> zope.component.provideAdapter(
... CSSResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='resource.css')
>>> CSSViewlet = viewlet.CSSViewlet('resource.css')
>>> print CSSViewlet(content, request, view, manager).render().strip()
You can also change the media type and the rel attribute:
>>> CSSViewlet = viewlet.CSSViewlet('resource.css', media='print', rel='css')
>>> print CSSViewlet(content, request, view, manager).render().strip()
There is also a bundle viewlet for CSS links:
>>> class CSSPrintResource(object):
... def __init__(self, request):
... self.request = request
...
... def __call__(self):
... return '/@@/print-resource.css'
>>> zope.component.provideAdapter(
... CSSPrintResource,
... (IDefaultBrowserLayer,),
... zope.interface.Interface, name='print-resource.css')
>>> items = []
>>> items.append({'path':'resource.css', 'rel':'stylesheet', 'media':'all'})
>>> items.append({'path':'print-resource.css', 'media':'print'})
>>> CSSBundleViewlet = viewlet.CSSBundleViewlet(items)
>>> print CSSBundleViewlet(content, request, view, manager).render().strip()
A Complex Example
-----------------
The Data
~~~~~~~~
So far we have only demonstrated simple (maybe overly trivial) use cases of
the viewlet system. In the following example, we are going to develop a
generic contents view for files. The step is to create a file component:
>>> class IFile(zope.interface.Interface):
... data = zope.interface.Attribute('Data of file.')
>>> class File(object):
... zope.interface.implements(IFile)
... def __init__(self, data=''):
... self.__name__ = ''
... self.data = data
Since we want to also provide the size of a file, here a simple implementation
of the ``ISized`` interface:
>>> from zope import size
>>> class FileSized(object):
... zope.interface.implements(size.interfaces.ISized)
... zope.component.adapts(IFile)
...
... def __init__(self, file):
... self.file = file
...
... def sizeForSorting(self):
... return 'byte', len(self.file.data)
...
... def sizeForDisplay(self):
... return '%i bytes' %len(self.file.data)
>>> zope.component.provideAdapter(FileSized)
We also need a container to which we can add files:
>>> class Container(dict):
... def __setitem__(self, name, value):
... value.__name__ = name
... super(Container, self).__setitem__(name, value)
Here is some sample data:
>>> container = Container()
>>> container['test.txt'] = File('Hello World!')
>>> container['mypage.html'] = File('Hello World!')
>>> container['data.xml'] = File('Hello World!')
The View
~~~~~~~~
The contents view of the container should iterate through the container and
represent the files in a table:
>>> contentsTemplate = os.path.join(temp_dir, 'contents.pt')
>>> open(contentsTemplate, 'w').write('''
...
...
...
Contents
...
...
...
... ''')
>>> from zope.browserpage.simpleviewclass import SimpleViewClass
>>> Contents = SimpleViewClass(contentsTemplate, name='contents.html')
The Viewlet Manager
~~~~~~~~~~~~~~~~~~~
Now we have to write our own viewlet manager. In this case we cannot use the
default implementation, since the viewlets will be looked up for each
different item:
>>> shownColumns = []
>>> class ContentsViewletManager(object):
... zope.interface.implements(interfaces.IViewletManager)
... index = None
...
... def __init__(self, context, request, view):
... self.context = context
... self.request = request
... self.__parent__ = view
...
... def update(self):
... rows = []
... for name, value in self.context.items():
... rows.append(
... [zope.component.getMultiAdapter(
... (value, self.request, self.__parent__, self),
... interfaces.IViewlet, name=colname)
... for colname in shownColumns])
... [entry.update() for entry in rows[-1]]
... self.rows = rows
...
... def render(self, *args, **kw):
... return self.index(*args, **kw)
Now we need a template to produce the contents table:
>>> tableTemplate = os.path.join(temp_dir, 'table.pt')
>>> open(tableTemplate, 'w').write('''
...
...
...
...
...
...
...
... ''')
From the two pieces above, we can generate the final viewlet manager class and
register it (it's a bit tedious, I know):
>>> from zope.browserpage import ViewPageTemplateFile
>>> ContentsViewletManager = type(
... 'ContentsViewletManager', (ContentsViewletManager,),
... {'index': ViewPageTemplateFile(tableTemplate)})
>>> zope.component.provideAdapter(
... ContentsViewletManager,
... (Container, IDefaultBrowserLayer, zope.interface.Interface),
... interfaces.IViewletManager, name='contents')
Since we have not defined any viewlets yet, the table is totally empty:
>>> contents = Contents(container, request)
>>> print contents().strip()
Contents
The Viewlets and the Final Result
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Now let's create a first viewlet for the manager...
>>> class NameViewlet(object):
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
... self.context = context
...
... def update(self):
... pass
...
... def render(self):
... return self.context.__name__
and register it:
>>> zope.component.provideAdapter(
... NameViewlet,
... (IFile, IDefaultBrowserLayer,
... zope.interface.Interface, interfaces.IViewletManager),
... interfaces.IViewlet, name='name')
Note how you register the viewlet on ``IFile`` and not on the container. Now
we should be able to see the name for each file in the container:
>>> print contents().strip()
Contents
Waaa, nothing there! What happened? Well, we have to tell our user preferences
that we want to see the name as a column in the table:
>>> shownColumns = ['name']
>>> print contents().strip()
Contents
mypage.html
data.xml
test.txt
Let's now write a second viewlet that will display the size of the object for
us:
>>> class SizeViewlet(object):
...
... def __init__(self, context, request, view, manager):
... self.__parent__ = view
... self.context = context
...
... def update(self):
... pass
...
... def render(self):
... return size.interfaces.ISized(self.context).sizeForDisplay()
>>> zope.component.provideAdapter(
... SizeViewlet,
... (IFile, IDefaultBrowserLayer,
... zope.interface.Interface, interfaces.IViewletManager),
... interfaces.IViewlet, name='size')
After we added it to the list of shown columns,
>>> shownColumns = ['name', 'size']
we can see an entry for it:
>>> print contents().strip()
Contents
mypage.html
38 bytes
data.xml
31 bytes
test.txt
12 bytes
If we switch the two columns around,
>>> shownColumns = ['size', 'name']
the result will be
>>> print contents().strip()
Contents
38 bytes
mypage.html
31 bytes
data.xml
12 bytes
test.txt
Supporting Sorting
~~~~~~~~~~~~~~~~~~
Oftentimes you also want to batch and sort the entries in a table. Since those
two features are not part of the view logic, they should be treated with
independent components. In this example, we are going to only implement
sorting using a simple utility:
>>> class ISorter(zope.interface.Interface):
...
... def sort(values):
... """Sort the values."""
>>> class SortByName(object):
... zope.interface.implements(ISorter)
...
... def sort(self, values):
... return sorted(values, lambda x, y: cmp(x.__name__, y.__name__))
>>> zope.component.provideUtility(SortByName(), name='name')
>>> class SortBySize(object):
... zope.interface.implements(ISorter)
...
... def sort(self, values):
... return sorted(
... values,
... lambda x, y: cmp(size.interfaces.ISized(x).sizeForSorting(),
... size.interfaces.ISized(y).sizeForSorting()))
>>> zope.component.provideUtility(SortBySize(), name='size')
Note that we decided to give the sorter utilities the same name as the
corresponding viewlet. This convention will make our implementation of the
viewlet manager much simpler:
>>> sortByColumn = ''
>>> class SortedContentsViewletManager(object):
... zope.interface.implements(interfaces.IViewletManager)
... index = None
...
... def __init__(self, context, request, view):
... self.context = context
... self.request = request
... self.__parent__ = view
...
... def update(self):
... values = self.context.values()
...
... if sortByColumn:
... sorter = zope.component.queryUtility(ISorter, sortByColumn)
... if sorter:
... values = sorter.sort(values)
...
... rows = []
... for value in values:
... rows.append(
... [zope.component.getMultiAdapter(
... (value, self.request, self.__parent__, self),
... interfaces.IViewlet, name=colname)
... for colname in shownColumns])
... [entry.update() for entry in rows[-1]]
... self.rows = rows
...
... def render(self, *args, **kw):
... return self.index(*args, **kw)
As you can see, the concern of sorting is cleanly separated from generating
the view code. In MVC terms that means that the controller (sort) is logically
separated from the view (viewlets). Let's now do the registration dance for
the new viewlet manager. We simply override the existing registration:
>>> SortedContentsViewletManager = type(
... 'SortedContentsViewletManager', (SortedContentsViewletManager,),
... {'index': ViewPageTemplateFile(tableTemplate)})
>>> zope.component.provideAdapter(
... SortedContentsViewletManager,
... (Container, IDefaultBrowserLayer, zope.interface.Interface),
... interfaces.IViewletManager, name='contents')
Finally we sort the contents by name:
>>> shownColumns = ['name', 'size']
>>> sortByColumn = 'name'
>>> print contents().strip()
Contents
data.xml
31 bytes
mypage.html
38 bytes
test.txt
12 bytes
Now let's sort by size:
>>> sortByColumn = 'size'
>>> print contents().strip()
Contents
test.txt
12 bytes
data.xml
31 bytes
mypage.html
38 bytes
That's it! As you can see, in a few steps we have built a pretty flexible
contents view with selectable columns and sorting. However, there is a lot of
room for extending this example:
- Table Header: The table header cell for each column should be a different
type of viewlet, but registered under the same name. The column header
viewlet also adapts the container not the item. The header column should
also be able to control the sorting.
- Batching: A simple implementation of batching should work very similar to
the sorting feature. Of course, efficient implementations should somehow
combine batching and sorting more effectively.
- Sorting in ascending and descending order: Currently, you can only sort from
the smallest to the highest value; however, this limitation is almost
superficial and can easily be removed by making the sorters a bit more
flexible.
- Further Columns: For a real application, you would want to implement other
columns, of course. You would also probably want some sort of fallback for
the case that a viewlet is not found for a particular container item and
column.
Cleanup
-------
>>> import shutil
>>> shutil.rmtree(temp_dir)
zope.viewlet-3.7.2/src/zope/viewlet/javascript_bundle_viewlet.pt 0000644 0001750 0001750 00000000243 11376754171 025123 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/viewlet/configure.zcml 0000644 0001750 0001750 00000000763 11376754171 022177 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/viewlet/css_viewlet.pt 0000644 0001750 0001750 00000000305 11376754171 022213 0 ustar tseaver tseaver
zope.viewlet-3.7.2/src/zope/viewlet/directives.txt 0000644 0001750 0001750 00000030654 11376754171 022233 0 ustar tseaver tseaver ================================
The ``viewletManager`` Directive
================================
The ``viewletManager`` directive allows you to quickly register a new viewlet
manager without worrying about the details of the ``adapter``
directive. Before we can use the directives, we have to register their
handlers by executing the package's meta configuration:
>>> from zope.configuration import xmlconfig
>>> context = xmlconfig.string('''
...
...
...
... ''')
Now we can register a viewlet manager:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Let's make sure the directive has really issued a sensible adapter
registration; to do that, we create some dummy content, request and view
objects:
>>> import zope.interface
>>> class Content(object):
... zope.interface.implements(zope.interface.Interface)
>>> content = Content()
>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> from zope.publisher.browser import BrowserView
>>> view = BrowserView(content, request)
Now let's lookup the manager. This particular registration is pretty boring:
>>> import zope.component
>>> from zope.viewlet import interfaces
>>> manager = zope.component.getMultiAdapter(
... (content, request, view),
... interfaces.IViewletManager, name='defaultmanager')
>>> manager
object ...>
>>> interfaces.IViewletManager.providedBy(manager)
True
>>> manager.template is None
True
>>> manager.update()
>>> manager.render()
u''
However, this registration is not very useful, since we did specify a specific
viewlet manager interface, a specific content interface, specific view or
specific layer. This means that all viewlets registered will be found.
The first step to effectively using the viewlet manager directive is to define
a special viewlet manager interface:
>>> class ILeftColumn(interfaces.IViewletManager):
... """Left column of my page."""
Now we can register register a manager providing this interface:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> manager = zope.component.getMultiAdapter(
... (content, request, view), ILeftColumn, name='leftcolumn')
>>> manager
object ...>
>>> ILeftColumn.providedBy(manager)
True
>>> manager.template is None
True
>>> manager.update()
>>> manager.render()
u''
Next let's see what happens, if we specify a template for the viewlet manager:
>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()
>>> leftColumnTemplate = os.path.join(temp_dir, 'leftcolumn.pt')
>>> open(leftColumnTemplate, 'w').write('''
...
Additionally you can specify a class that will serve as a base to the default
viewlet manager or be a viewlet manager in its own right. In our case we will
provide a custom implementation of the ``sort()`` method, which will sort by a
weight attribute in the viewlet:
>>> class WeightBasedSorting(object):
... def sort(self, viewlets):
... return sorted(viewlets,
... lambda x, y: cmp(x[1].weight, y[1].weight))
>>> context = xmlconfig.string('''
...
...
...
... ''' %leftColumnTemplate, context=context)
>>> manager = zope.component.getMultiAdapter(
... (content, request, view), ILeftColumn, name='leftcolumn')
>>> manager
object ...>
>>> manager.__class__.__bases__
(,
)
>>> ILeftColumn.providedBy(manager)
True
>>> manager.template
...>>
>>> manager.update()
>>> print manager.render().strip()
Finally, if a non-existent template is specified, an error is raised:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-7.8
ConfigurationError: ('No such file', '...foo.pt')
=========================
The ``viewlet`` Directive
=========================
Now that we have a viewlet manager, we have to register some viewlets for
it. The ``viewlet`` directive is similar to the ``viewletManager`` directive,
except that the viewlet is also registered for a particular manager interface,
as seen below:
>>> weatherTemplate = os.path.join(temp_dir, 'weather.pt')
>>> open(weatherTemplate, 'w').write('''
...
sunny
... ''')
>>> context = xmlconfig.string('''
...
...
...
... ''' % weatherTemplate, context=context)
If we look into the adapter registry, we will find the viewlet:
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='weather')
>>> viewlet.render().strip()
u'
sunny
'
>>> viewlet.extra_string_attributes
u'can be specified'
The manager now also gives us the output of the one and only viewlet:
>>> manager.update()
>>> print manager.render().strip()
sunny
Let's now ensure that we can also specify a viewlet class:
>>> class Weather(object):
... weight = 0
>>> context = xmlconfig.string('''
...
...
...
... ''' % weatherTemplate, context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='weather2')
>>> viewlet().strip()
u'
sunny
'
Okay, so the template-driven cases work. But just specifying a class should
also work:
>>> class Sport(object):
... weight = 0
... def __call__(self):
... return u'Red Sox vs. White Sox'
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet, name='sport')
>>> viewlet()
u'Red Sox vs. White Sox'
It should also be possible to specify an alternative attribute of the class to
be rendered upon calling the viewlet:
>>> class Stock(object):
... weight = 0
... def getStockTicker(self):
... return u'SRC $5.19'
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='stock')
>>> viewlet.render()
u'SRC $5.19'
A final feature the ``viewlet`` directive is that it supports the
specification of any number of keyword arguments:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
>>> viewlet = zope.component.getMultiAdapter(
... (content, request, view, manager), interfaces.IViewlet,
... name='stock2')
>>> viewlet.weight
u'8'
Error Scenarios
---------------
Neither the class or template have been specified:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-7.8
ConfigurationError: Must specify a class or template
The specified attribute is not ``__call__``, but also a template has been
specified:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-9.8
ConfigurationError: Attribute and template cannot be used together.
Now, we are not specifying a template, but a class that does not have the
specified attribute:
>>> context = xmlconfig.string('''
...
...
...
... ''', context=context)
Traceback (most recent call last):
...
ZopeXMLConfigurationError: File "", line 3.2-9.8
ConfigurationError: The provided class doesn't have the specified attribute
Cleanup
-------
>>> import shutil
>>> shutil.rmtree(temp_dir)
zope.viewlet-3.7.2/src/zope/viewlet/viewlet.py 0000644 0001750 0001750 00000015136 11376754171 021360 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Viewlet implementation
$Id: viewlet.py 112059 2010-05-05 19:40:35Z tseaver $
"""
__docformat__ = 'restructuredtext'
import os
import sys
import zope.interface
from zope.traversing import api
from zope.publisher.browser import BrowserView
from zope.viewlet import interfaces
from zope.browserpage import simpleviewclass
from zope.browserpage import ViewPageTemplateFile
class ViewletBase(BrowserView):
"""Viewlet adapter class used in meta directive as a mixin class."""
zope.interface.implements(interfaces.IViewlet)
def __init__(self, context, request, view, manager):
super(ViewletBase, self).__init__(context, request)
self.__parent__ = view
self.context = context
self.request = request
self.manager = manager
def update(self):
pass
def render(self):
raise NotImplementedError(
'`render` method must be implemented by subclass.')
class SimpleAttributeViewlet(ViewletBase):
"""A viewlet that uses a specified method to produce its content."""
def render(self, *args, **kw):
# If a class doesn't provide it's own call, then get the attribute
# given by the browser default.
attr = self.__page_attribute__
if attr == 'render':
raise AttributeError("render")
meth = getattr(self, attr)
return meth(*args, **kw)
class simple(simpleviewclass.simple):
"""Simple viewlet class supporting the ``render()`` method."""
render = simpleviewclass.simple.__call__
def SimpleViewletClass(template, offering=None, bases=(), attributes=None,
name=u''):
"""A function that can be used to generate a viewlet from a set of
information.
"""
# Get the current frame
if offering is None:
offering = sys._getframe(1).f_globals
# Create the base class hierarchy
bases += (simple, ViewletBase)
attrs = {'index' : ViewPageTemplateFile(template, offering),
'__name__' : name}
if attributes:
attrs.update(attributes)
# Generate a derived view class.
class_ = type("SimpleViewletClass from %s" % template, bases, attrs)
return class_
class ResourceViewletBase(object):
"""A simple viewlet for inserting references to resources.
This is an abstract class that is expected to be used as a base only.
"""
_path = None
def getURL(self):
resource = api.traverse(self.context, '++resource++' + self._path,
request=self.request)
return resource()
def render(self, *args, **kw):
return self.index(*args, **kw)
def JavaScriptViewlet(path):
"""Create a viewlet that can simply insert a javascript link."""
src = os.path.join(os.path.dirname(__file__), 'javascript_viewlet.pt')
klass = type('JavaScriptViewlet',
(ResourceViewletBase, ViewletBase),
{'index': ViewPageTemplateFile(src),
'_path': path})
return klass
class CSSResourceViewletBase(ResourceViewletBase):
_media = 'all'
_rel = 'stylesheet'
def getMedia(self):
return self._media
def getRel(self):
return self._rel
def CSSViewlet(path, media="all", rel="stylesheet"):
"""Create a viewlet that can simply insert a CSS link."""
src = os.path.join(os.path.dirname(__file__), 'css_viewlet.pt')
klass = type('CSSViewlet',
(CSSResourceViewletBase, ViewletBase),
{'index': ViewPageTemplateFile(src),
'_path': path,
'_media':media,
'_rel':rel})
return klass
class ResourceBundleViewletBase(object):
"""A simple viewlet for inserting references to different resources.
This is an abstract class that is expected to be used as a base only.
"""
_paths = None
def getResources(self):
resources = []
append = resources.append
for path in self._paths:
append(api.traverse(self.context, '++resource++' + path,
request=self.request))
return resources
def render(self, *args, **kw):
return self.index(*args, **kw)
def JavaScriptBundleViewlet(paths):
"""Create a viewlet that can simply insert javascript links."""
src = os.path.join(os.path.dirname(__file__),
'javascript_bundle_viewlet.pt')
klass = type('JavaScriptBundleViewlet',
(ResourceBundleViewletBase, ViewletBase),
{'index': ViewPageTemplateFile(src),
'_paths': paths})
return klass
class CSSResourceBundleViewletBase(object):
"""A simple viewlet for inserting css references to different resources.
There is a tuple or list of dict used for the different resource
descriptions. The list of dict uses the following format:
({path:'the path', media:'all', rel:'stylesheet'},...)
The default values for media is ``all`` and the default value for rel is
``stylesheet``. The path must be set there is no default value for the
path attribute.
This is an abstract class that is expected to be used as a base only.
"""
_items = None
def getResources(self):
resources = []
append = resources.append
for item in self._items:
info = {}
info['url'] = api.traverse(self.context,
'++resource++' + item.get('path'), request=self.request)
info['media'] = item.get('media', 'all')
info['rel'] = item.get('rel', 'stylesheet')
append(info)
return resources
def render(self, *args, **kw):
return self.index(*args, **kw)
def CSSBundleViewlet(items):
"""Create a viewlet that can simply insert css links."""
src = os.path.join(os.path.dirname(__file__),
'css_bundle_viewlet.pt')
klass = type('CSSBundleViewlet',
(CSSResourceBundleViewletBase, ViewletBase),
{'index': ViewPageTemplateFile(src),
'_items': items})
return klass
zope.viewlet-3.7.2/src/zope/viewlet/tests.py 0000644 0001750 0001750 00000005571 11376754171 021045 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Viewlet tests
$Id: tests.py 112059 2010-05-05 19:40:35Z tseaver $
"""
__docformat__ = 'restructuredtext'
import os
import doctest
import sys
import unittest
import zope.component
from zope.testing import cleanup
from zope.traversing.testing import setUp as traversingSetUp
from zope.component import eventtesting
def setUp(test):
cleanup.setUp()
eventtesting.setUp()
traversingSetUp()
# resource namespace setup
from zope.traversing.interfaces import ITraversable
from zope.traversing.namespace import resource
zope.component.provideAdapter(
resource, (None,), ITraversable, name = "resource")
zope.component.provideAdapter(
resource, (None, None), ITraversable, name = "resource")
from zope.browserpage import metaconfigure
from zope.contentprovider import tales
metaconfigure.registerType('provider', tales.TALESProviderExpression)
def tearDown(test):
cleanup.tearDown()
class FakeModule(object):
"""A fake module."""
def __init__(self, dict):
self.__dict = dict
def __getattr__(self, name):
try:
return self.__dict[name]
except KeyError:
raise AttributeError(name)
def directivesSetUp(test):
setUp(test)
test.globs['__name__'] = 'zope.viewlet.directives'
sys.modules['zope.viewlet.directives'] = FakeModule(test.globs)
def directivesTearDown(test):
tearDown(test)
del sys.modules[test.globs['__name__']]
test.globs.clear()
def test_suite():
return unittest.TestSuite((
doctest.DocFileSuite('README.txt',
setUp=setUp, tearDown=tearDown,
optionflags=doctest.NORMALIZE_WHITESPACE|doctest.ELLIPSIS,
globs = {'__file__': os.path.join(
os.path.dirname(__file__), 'README.txt')}
),
doctest.DocFileSuite('directives.txt',
setUp=directivesSetUp, tearDown=directivesTearDown,
optionflags=doctest.NORMALIZE_WHITESPACE|doctest.ELLIPSIS,
globs = {'__file__': os.path.join(
os.path.dirname(__file__), 'directives.txt')}
),
))
if __name__ == '__main__':
unittest.main(defaultTest='test_suite')
zope.viewlet-3.7.2/src/zope/viewlet/__init__.py 0000644 0001750 0001750 00000001273 11376754171 021435 0 ustar tseaver tseaver ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""
$Id: __init__.py 112059 2010-05-05 19:40:35Z tseaver $
"""
zope.viewlet-3.7.2/src/zope/__init__.py 0000644 0001750 0001750 00000000070 11376754171 017750 0 ustar tseaver tseaver __import__('pkg_resources').declare_namespace(__name__)
zope.viewlet-3.7.2/LICENSE.txt 0000644 0001750 0001750 00000004026 11376754171 015723 0 ustar tseaver tseaver Zope Public License (ZPL) Version 2.1
A copyright notice accompanies this license document that identifies the
copyright holders.
This license has been certified as open source. It has also been designated as
GPL compatible by the Free Software Foundation (FSF).
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions in source code must retain the accompanying copyright
notice, this list of conditions, and the following disclaimer.
2. Redistributions in binary form must reproduce the accompanying copyright
notice, this list of conditions, and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. Names of the copyright holders must not be used to endorse or promote
products derived from this software without prior written permission from the
copyright holders.
4. The right to distribute this software or to use it for any purpose does not
give you the right to use Servicemarks (sm) or Trademarks (tm) of the
copyright
holders. Use of them is covered by separate agreement with the copyright
holders.
5. If any files are modified, you must cause the modified files to carry
prominent notices stating that you changed the files and the date of any
change.
Disclaimer
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY EXPRESSED
OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.