Integrates the xdv Deliverance implementation with Plone using a post-publication hook to transform content

## Project description

============
Introduction
============

This package services for applying a transformation to Plone's HTML output,
using the XDV compiler. XDV is an implementation of Deliverance, specifically
the original Deliverance XML-based syntax. It works by compiling the theme
(an HTML file) and rules (an XML file) into a single XSLT file, which is then
applied to Plone's HTML on render.

collective.xdv uses a post-publication hook made available through the
plone.postpublicationhook package to modify the request as it is is sent
to the browser. If you are using repoze.zope2 or another WSGI-based solution
for hosting Zope, it may be better to simply apply the transform in the
WSGI pipeline, using dv.xdvserver (on which this package depends). However,
for a standard Plone 3.x, this package provides a tightly integrated solution.

Dependencies
------------

collective.xdv depends on:

* plone.registry and plone.app.registry to manage settings
* plone.autoform, plone.z3cform and plone.app.z3cform to render the
control panel
* dv.xdvserver to compile the XDV theme
* lxml to perform the final transform

These will all be pulled in automatically if you are using zc.buildout, but
note that you may need to configure your buildout with a few overridden
versions of some core packages. Your buildout should contain the following::

[buildout]
...
versions = versions

[versions]
zope.i18n = 3.4.0
zope.testing = 3.4.0
zope.component = 3.4.0
...

[zope2]
recipe = plone.recipe.zope2install
fake-zope-eggs = true
skip-fake-eggs =
zope.component
zope.testing
zope.i18n
...

If you are on OSX, you may also want to use the following recipe to correctly
configure lxml::

[buildout]
parts =
lxml
...
versions = versions

[versions]
...
lxml = 2.1.5
...

[lxml]
recipe = z3c.recipe.staticlxml
egg = lxml
force = false

This tells buildout to use newer versions of these three packages. You will
of course also need to load the package as an egg dependency and include its
ZCML as normal, e.g::

[instance]
recipe = plone.recipe.zope2instance
eggs =
collective.xdv
...
zcml =
collective.xdv
...
...

Usage
-----

The publication hook is installed automatically, but will not do anything
unless xdv is configured for a particular Plone site. To do that, first
install it in the quickinstaller as normal, and then go to the new "Theme
transform" control panel. Here, you can set the following options:

Enabled yes/no
Whether or not the transform is enabled.

Domains
A list of domains (including ports) that will be matched against
the HOST header to determine if the theme should be applied. Note that
127.0.0.1 is never styled, to ensure there's always a way back into Plone
to change these very settings. However, 'localhost' should work just fine.

Theme
A file path or URL pointing to the theme file. This is just a
static HTML file.

Rules
The filesystem path to the rules XML file.

Boilerplate
XDV by default includes some 'boilerplate' XSLT that takes
care of copying some basic header attributes. You can override the
boilerplate XSL file by specifying a filename here.

Absolute prefix
If given, any relative URL in an <img />,
<link />, <style /> or <script /> in the theme HTML file will
be prefixed by this URL snippet when the theme is compiled. This makes it
easier to develop theme HTML/CSS on the file system using relative paths
that still work on any URL on the server.

Unstyled paths
This is used to give a list of URL patterns (using regular
expression syntax) for pages that will not be styled even if XDV is
enabled. By default, this includes the 'emptypage' view that is necessary
for the Kupu editor to work, and the manage_* pages that make up the
ZMI.

Note that when Zope is in debug mode, the theme will be re-compiled on each
request. In non-debug mode, it is compiled once on startup, and then only
if the control panel values are changed.

Static files and CSS
--------------------

Typically, the theme will reference static resources such as images or
stylesheets. It is usually a good idea to keep all of these in a single,
top-level directory to minimise the risk of clashes with Plone content paths.

If you are using Zope/Plone standalone, you will need to make your static
resources available through Zope, or serve them from a separate (sub-)domain.
The easiest way to do this is via a Plone folder with files, but a skin layer
directory view in portal_skins may also work.

If you have put Apache, nginx or IIS in front of Zope, you may want to serve
the static resources from the web server directly.

Controlling Plone's default CSS
-------------------------------

It is sometimes useful to show some of Plone's CSS in the styled site. You
can achieve this by using an xdv <append /> rule or similar to copy the
CSS from Plone's generated <head /> into the theme. You can use the portal_css
tool to turn off the style sheets you do not want.

However, if you also want the site to be usable in non-themed mode (e.g. on
a separate URL), you may want to have a larger set of styles enabled when
xdv is not used. To make this easier, you can use the following expressions
as conditions in portal_css (and portal_javascripts, portal_kss,
portal_actions, in page templates, and other places that use TAL expression
syntax):

portal/@@xdv-check/enabled
Will return True if xdv is currently
enabled. This will check both the 'enabled' flag in the Theme Transform
settings, and the current domain. Use 'not: portal/@@xdv-check/enabled'
to 'hide' a style sheet from the themed site.

portal/@@xdv-check/domain_enabled
Similar to the 'enabled' check, but
only checks the domain, not the global 'enabled' flag in the control
panel. This is useful if you want to apply the xdv transform outside
Plone, but still need a way to control which domains get which styles.

Interaction with CacheFu
-------------------------

If you are using collective.xdv with Plone's CacheFu system, you will need
to disable GZIP compression in CacheFu's control panel. You may use
compression in e.g. Apache or nginx in front of Zope, but you can't apply
the compression before the xdv transform.

Changelog
=========

1.0a1 - 2009-04-17
------------------

* Initial release

## Project details

Uploaded source