--- a/src/source/dev_guide/tales.rst Thu Dec 20 17:59:43 2018 +0100
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,74 +0,0 @@
-.. _tales:
-
-Custom TALES extensions
-=======================
-
-PyAMS defines a custom expression for TALES called *extension*.
-
-When this expression is encountered, the renderer is looking for an
-:py:class:`ITALESExtension <pyams_utils.interfaces.tales.ITALESExtension>`
-multi-adapter for the current *context*, *request* and *view*, for the current
-*context* and *request*, or only for the current *context*, in this order.
-If an adapter is found, the renderer call it's :py:func:`render` method with
-the expression parameters as input parameters.
-
-For example, the *metas* extension is an *ITALESExtension* adapter defined into
-:py:mod:`pyams_skin.metas` module which can be used to include all required headers in
-a page template. Extension is used like this in the page layout template:
-
-.. code-block:: html
-
- <tal:var replace="structure extension:metas" />
-
-This extension is defined like this:
-
-.. code-block:: python
-
- from pyams_skin.interfaces.metas import IHTMLContentMetas
- from pyams_utils.interfaces.tales import ITALESExtension
- from pyramid.interfaces import IRequest
-
- from pyams_utils.adapter import adapter_config, ContextRequestViewAdapter
-
- @adapter_config(name='metas', context=(Interface, IRequest, Interface), provides=ITALESExtension)
- class MetasTalesExtension(ContextRequestViewAdapter):
- '''extension:metas TALES extension'''
-
- def render(self, context=None):
- if context is None:
- context = self.context
- result = []
- for name, adapter in sorted(self.request.registry.getAdapters((context, self.request, self.view),
- IHTMLContentMetas),
- key=lambda x: getattr(x[1], 'order', 9999)):
- result.extend([meta.render() for meta in adapter.get_metas()])
- return '\n\t'.join(result)
-
-Some TALES extensions can require or accept arguments. For example, the *absolute_url* extension can accept
-a context and a view name:
-
-.. code-block:: html
-
- <tal:var define="logo config.logo">
- <img tal:attributes="src extension:absolute_url(logo, '++thumb++200x36.png');" />
- </tal:var>
-
-The extension is defined like this:
-
-.. code-block:: python
-
- from persistent.interfaces import IPersistent
- from pyams_utils.interfaces.tales import ITALESExtension
-
- from pyams_utils.adapter import adapter_config, ContextRequestViewAdapter
- from pyramid.url import resource_url
- from zope.interface import Interface
-
- @adapter_config(name='absolute_url', context=(IPersistent, Interface, Interface), provides=ITALESExtension)
- class AbsoluteUrlTalesExtension(ContextRequestViewAdapter):
- '''extension:absolute_url(context, view_name) TALES extension'''
-
- def render(self, context=None, view_name=None):
- if context is None:
- context = self.context
- return resource_url(context, self.request, view_name)