Version 3 (modified by 12 years ago) ( diff ) | ,
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Extension Point : IWikiMacroProvider
Interface | IWikiMacroProvider | Since | 0.9 |
Module | trac.wiki | Source | api.py |
The IWikiMacroProvider allows adding new WikiMacros.
Purpose
Trac provides an extensible wiki system. WikiMacros are a flexible and powerful way to add new functionality with a standardized and familiar syntax.
All macros are also WikiProcessors automatically and can thus be used with block syntax.
To add not only new functionality, but also new syntax to the wiki system, use a trac.wiki.api.IWikiSyntaxProvider.
Usage
Implementing the interface follows the standard guidelines found in TracDev/ComponentArchitecture and of course TracDev/PluginDevelopment.
A class implementing IWikiMacroProvider directly can provide multiple macros by returning their names from get_macros
. The expand_macro
method is then called each time one of these macros is rendered.
That method should render the macro invocation, by returning the expanded HTML string. The name of the macro to be invoked in the name
parameter.
The arguments to the macro are passed in the content
parameter as a single string. If multiple separate arguments should be supported, this string can be parsed using trac.wiki.api.parse_args
.
A further parameter formatter
provides access to various useful objects:
formatter.resource
(a trac.resource.Resource)
The resource identifier which owns the text being formatted. (E.g. a wiki page, whereformatter.resource.id
is the page name.)formatter.perm
(a trac.perm.PermissionCache)
The permission cache which can be used to perform fine-grained permission checks.formatter.href
(a trac.web.Href)
The URL builder.formatter.wiki
(a trac.wiki.api.WikiSystem)
The wiki system can be used to access wiki pages.formatter.wikiparser
(a trac.wiki.parser.WikiParser)
The wiki parser.formatter.context
(a trac.mimeview.api.RenderingContext)
The rendering context in which this wiki formatting takes place.formatter.req
(a trac.web.api.Request)
The web request. (to be deprecated)
In case the macro was invoked using wiki processor syntax, an additional args
parameter contains the dictionary of wiki processor syntax arguments, while content
contains the code block content.
A simpler way to implement the interface is to derive a class from trac.wiki.macros.WikiMacroBase for each macro. That way the macro's name is automatically the same as the class name, and only the expand_macro
method has to be implemented.
(The render_macro
method is deprecated and can be ignored. It was used in macros for Trac 0.9 and 0.10.)
Examples
The following example macro allows using the HTML5 <audio/>
element (available in recent browser) to play audio files:
from genshi.builder import tag from trac.wiki.macros import WikiMacroBase from trac.wiki.api import parse_args from trac.core import TracError class AudioMacro(WikiMacroBase): """Embed an audio element in wiki-formatted text. The first argument is the URL of the audio file to be played. Example: {{{ [[Audio(http://images.wikia.com/lotr/images/e/e5/HelmsDeepSound.ogg)]] }}} """ def expand_macro(self, formatter, name, content): args, kw = parse_args(content) if not args: raise TracError('No audio file found') return tag.audio(src=args[0], autoplay='', controls='')( "Your browser does not support audio.")
Available Implementations
- Macros in Trac
- Sample Plugins
- Default macros
- Based on
WikiMacroBase
- Part of another component implementing
IWikiSyntaxProvider
directly:
- Based on
- CommitTicketReferenceMacro (Optional macro from from
tracopt
) - various simple test macros used for unit testing
- In third-party plugins:
Additional Information and References
- epydoc
- API Reference
- WikiMacros#DevelopingCustomMacros
- Related to the trac.wiki.api.IWikiSyntaxProvider
- Related tickets:
- wiki system component
- macro keywords
- #10038 Translated macro descriptions
- #10201 Detailed help for WikiProcessors