Package: z3c.macroviewlet
Macro viewlets are Zope 3 UI components. In particular they allow the developer
to specify viewlets based on macros instead of entire templates.ContentsMacro ProviderLayout templateMacroViewletCleanupChanges1.1.0 (2010-07-14)1.0.0 (2007-09-21)Macro ProviderThis package provides a ZCML directive which allows you to register a macro
defined in a template as a viewlet. Such a macro based viewlet acts 100% the
same as a other viewlets. It could be very handy if you want to write a layout
template in one page template and define selective parts as viewlets without
adding any additional HTML. Let me show what this will look like:The layout/master template can look like this:<!DOCTYPE ...>
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"
      i18n:domain="z3c">
<head>
<tal:block replace="structure provider:ITitle">
  <metal:block define-macro="title">
    <title>The title</title>
  </metal:block>
</tal:block>
</head>
<body tal:define="applicationURL request/getApplicationURL">
<div id="content">
  <tal:block content="structure provider:pagelet">content</tal:block>
</div>
</div>
</body>
</html>The tempalte above defines an ITitle provider which contains the definition
for a macro within itself. You have to define a viewlet manager within the
zope.viewlet ZCMl directive which provides ITitle as a viewlet manager.
After that, you can register the template above as a layout template wthin
the z3c:layout ZCML directive like this:<z3c:layout
    for="*"
    layer="z3c.skin.pagelet.IPageletBrowserSkin"
    template="template.pt"
    />Then you can register the macro viewlet for the ITitle viewlet manager
like this:<z3c:macroViewlet
    for="*"
    template="template.pt"
    macro="title"
    manager="z3c.skin.pagelet.ITitle"
    layer="z3c.skin.pagelet.IPageletBrowserSkin"
    />As you can see, the ZCML configuration directive above usestitleas the
macro attribute and uses ITitle as the viewlet manager. This will use the
following part of the template.pt:<title>Pagelet skin</title>and registers it as a viewlet. This viewlet gets rendered in the ITitle
provider. As you can see, you can use a complete layout tempalte and use it
as it is. And here it comes, you can offer an included viewlet manager
rendering the viewlet which can be overriden for other contexts or views etc.
You also can register more than one viewlet for the ITitle viewlet manager.
Which of course makes no sense in our special title tag example.Let’s show this in some tests. We’ll start by creating a content object that
is used as a view context later:>>> import zope.interface
>>> import zope.component
>>> from zope.publisher.interfaces.browser import IBrowserView
>>> from zope.publisher.interfaces.browser import IDefaultBrowserLayer
>>> class Content(object):
...     zope.interface.implements(zope.interface.Interface)

>>> content = Content()We also create a temp dir for sample templates which will be defined later
for testing:>>> import os, tempfile
>>> temp_dir = tempfile.mkdtemp()And we register a security checker for the MacroViewlet class:>>> from zope.configuration.xmlconfig import XMLConfig
>>> import zope.app.component
>>> import z3c.macroviewlet
>>> XMLConfig('meta.zcml', zope.app.component)()
>>> XMLConfig('configure.zcml', z3c.macroviewlet)()Layout templateWe define a template including a macro definition and using a provider:>>> path = os.path.join(temp_dir, 'template.pt')
>>> open(path, 'w').write('''
... <html>
... <body>
... <head>
... <tal:block replace="structure provider:ITitle">
...   <metal:block define-macro="title">
...     <title>The title</title>
...   </metal:block>
... </tal:block>
... </head>
... <body tal:define="applicationURL request/getApplicationURL">
...   content
... </body>
... </html>
... ''')Let’s register a view class using the view template:>>> import zope.interface
>>> from zope.app.pagetemplate import viewpagetemplatefile
>>> from zope.publisher.interfaces.browser import IBrowserView
>>> class View(object):
...     zope.interface.implements(IBrowserView)
...     def __init__(self, context, request):
...        self.context = context
...        self.request = request
...     def __call__(self):
...         return viewpagetemplatefile.ViewPageTemplateFile(path)(self)Let’s prepare the view:>>> from zope.publisher.browser import TestRequest
>>> request = TestRequest()
>>> view = View(content, request)Let’s define the viewlet managerITitle:>>> from zope.viewlet.interfaces import IViewletManager
>>> from zope.viewlet.manager import ViewletManager
>>> class ITitle(IViewletManager):
...     """Viewlet manager located in the title tag."""

>>> title = ViewletManager('title', ITitle)Let’s register the viewlet manager:>>> from zope.viewlet.interfaces import IViewletManager
>>> manager = zope.component.provideAdapter(
...     title,
...     (zope.interface.Interface, TestRequest, IBrowserView),
...     IViewletManager,
...     name='ITitle')MacroViewletBefore we register the macro viewlet, we check the rendered page without any
registered macro viewlet:>>> print view()
<html>
<body>
<head>
</head>
<body>
  content
</body>
</body></html>As you can see there is no title rendered. Now we can define the macro
viewlet…:>>> from zope.app.pagetemplate import viewpagetemplatefile
>>> from z3c.macroviewlet import zcml
>>> macroViewlet = zcml.MacroViewletFactory(path, 'title', 'text/html')and register them as adapter:>>> from zope.viewlet.interfaces import IViewlet
>>> zope.component.provideAdapter(
...     macroViewlet,
...     (zope.interface.Interface, IDefaultBrowserLayer, IBrowserView,
...      ITitle),
...     IViewlet,
...     name='title')Now we are ready to test it again:>>> print view()
<html>
<body>
<head>
    <title>The title</title>
</head>
<body>
  content
</body>
</body></html>As you can see, the title gets rendered as a viewlet into the ITitle provider.Cleanup>>> import shutil
>>> shutil.rmtree(temp_dir)Changes1.1.0 (2010-07-14)Fixed tests to run with current package versions
(metaconfigure.registerTypemoved fromzope.app.pagetemplatetozope.browserpage). Thus requiringzope.browserpagenow.No longer use depreactedzope.testing.doctestandzope.testing.doctestunit.Removed ZPKG and ZCML slugs.Fixed RST formatting in README.1.0.0 (2007-09-21)Initial Release