Author: Plone Foundation



A registry for linked Stylesheet and Javascript files.

This registry is mainly aimed at solving the following usecases:

- Enable product authors to register stylesheets with their product
  installers without having to resort to override either or
  ploneCustom.css creating potential conflicts with other products.

- Enable more componentialization of the stylesheets provided with Plone
  (and other products) without having to increase the number of http
  requests for a Plone page.

- Enable condition checking on stylesheets. Great for variable
  look-and-feel for groups/roles/folders/departments/content-types/etc

- Enable inline dynamic stylesheets. For those style rules that should
  vary for each request. Mainly used for things like header-bar-
  backgroundimages, department colors etc.

- Enable developers to activate/deactivate their styles in a simpler way

- Enable compression to safe bandwidth and download time


The CSSRegistry and JSRegistry are configured through the ZMI. They can be
found in the ZMI of your plonesite as 'portal_css' and 'portal_javascript'.

Add links to stylesheets that exist in your skins paths, by ids;  like
'plone.css', 'ploneCustom.css' etc.

Linked stylesheets take some parameters:

id -- The id mentioned above. the Zope id of the stylesheet to be used.

bundle -- A resource bundle is like a tag, which can be applied to each
resource. The default (implicit) bundle is called 'default', but other names
can be used. Bundles are associated with themes (skins) on the 'Bundles' tab
in the ZMI. Note that the same association applies to all resource registries,
i.e. this is a global setting. Bundles act like a filter - only resources in
the bundles listed for the current theme will be included.

expression -- A CMF expression to be evaluated to check if the stylesheet
should be included in output or not.

authenticated -- Restrict the resource to authenticated users. If this is
set, the expression is not evaluated.

conditionalcomment -- A small string to be included in a conditional comment
around the resource. For example, entering simply 'IE' in the field will
result in a conditional comment of: <!--[if IE]>...<![endif]--> This behavior
is currently only enabled for the CSS Registry. For more information see:

media -- The media for which the stylesheet should apply, normally empty or
'all'. other possible values are 'screen', 'print' etc.

rel -- Link relation. defaults to 'stylesheet', and should almost always
stay that way. For designating alternative stylesheets.

title -- the title for alternate stylesheets

rendering -- How to link the stylesheet from the html page:

- 'import' - the default. normal css import

- 'link' - works better for old browsers and is needed for alternate

- 'inline' - render the stylesheet inline instead of linking it
             Shouldn't be used at all!
             It isn't possible to create sites which validate if you do.
             For more information see:

compression -- Whether and how much the resource should be compressed:

- 'none' - the original content will not be changed

- 'safe' - the content will be compressed in a way which should be safe
           for any workarounds for browser bugs. Conditional code for
           Internet Explorer is preserved since ResourceRegistries
           1.2.3 and 1.3.1.

- 'full' - the content will be compressed with some additional rules.
           For css all comments and most newlines are removed, this may
           break special browser hacks, so use with care.
           For javascript this encodes variables with special prefixes
           according to the rules described here (Special Characters):
           The source code needs to be written according to those rules,
           otherwise it's more than l