Wiki Processors
Processors are WikiMacros that provide alternative markup formats for the Wiki engine. Processors can be thought of as macro functions to process user-edited text.
Wiki processors can be used in any Wiki text throughout Trac, such as:
- syntax highlighting or for rendering text verbatim
- rendering Wiki markup inside a context such as <div> or <span> blocks or within <td> or <th> table cells
- using an alternative markup syntax, like raw HTML and Restructured Text or textile
Using Processors
To use a processor on a block of text, first delimit the lines using a Wiki code block:
{{{
The lines
that should be processed...
}}}
Immediately after the {{{ or on the line just below, add #! followed by the processor name:
{{{
#!processorname
The lines
that should be processed...
}}}
This is the "shebang" notation, familiar to most UNIX users.
Besides their content, some Wiki processors can also accept parameters, which are then given as key=value pairs after the processor name and on the same line. If value has to contain space, as it's often the case for the style parameter, a quoted string can be used (key="value with space").
As some processors are meant to process Wiki markup, it's quite possible to nest processor blocks. You may want to indent the content of nested blocks for increased clarity, this extra indentation will be ignored when processing the content.
Examples
| Wiki Markup | Display |
|---|---|
| |
{{{
#!html
<h1 style="color: grey">This is raw HTML</h1>
}}}
| This is raw HTML |
| |
{{{#!div style="background: #ffd; border: 3px ridge"
This is an example of embedded "code" block:
{{{
#!python
def hello():
return "world"
}}}
}}}
| This is an example of embedded "code" block: def hello(): return "world" |
| |
{{{
#!html
<form action="/query" method="get"><div>
<input type="text" name="keywords" value="~" size="30"/>
<input type="submit" value="Search by Keywords"/>
<!-- To control what fields show up use hidden fields
<input type="hidden" name="col" value="id"/>
<input type="hidden" name="col" value="summary"/>
<input type="hidden" name="col" value="status"/>
<input type="hidden" name="col" value="milestone"/>
<input type="hidden" name="col" value="version"/>
<input type="hidden" name="col" value="owner"/>
<input type="hidden" name="col" value="priority"/>
<input type="hidden" name="col" value="component"/>
-->
</div></form>
}}}
| |
Available Processors
The following processors are included in the Trac distribution:
#!default | Present the text verbatim in a preformatted text block. This is the same as specifying no processor name (and no #!).
|
#!comment | Do not process the text in this section, i.e. contents exist only in the plain text - not in the rendered page. |
#!rtl | Introduce a Right-To-Left block with appropriate CSS direction and styling. (since 0.12.2) |
#!html | Insert custom HTML in a wiki page. |
#!htmlcomment | Insert an HTML comment in a wiki page. (since 0.12) |
Note that #!html blocks have to be self-contained, i.e. you can't start an HTML element in one block and close it later in a second block. Use the following processors for achieving a similar effect.
| |
#!div | Wrap wiki content inside a <div> element. |
#!span | Wrap wiki content inside a <span> element. |
#!td | Wrap wiki content inside a <td> element. (since 0.12) |
#!th | Wrap wiki content inside a <th> element. (since 0.12) |
#!tr | Can optionally be used for wrapping #!td and #!th blocks, either for specifying row attributes or better visual grouping. (since 0.12)
|
#!table | Can optionally be used for wrapping #!tr, #!td and #!th blocks, for specifying table attributes. One current limitation however is that tables cannot be nested. (since 0.12)
|
| See WikiHtml for example usage and more details about these processors. | |
| Other Markups | |
#!rst | Trac support for Restructured Text. See WikiRestructuredText. |
#!textile | Supported if Textile is installed. See a Textile reference. |
| Code Highlighting Support | |
#!c #!cpp (C++) #!python #!perl #!ruby #!php #!asp #!java #!js (Javascript) #!sql #!xml (XML or HTML) #!sh (Bourne/Bash shell) | Trac includes processors to provide inline syntax highlighting for source code in various languages. Trac relies on Pygments for syntax coloring. See TracSyntaxColoring for information about which languages are supported and how to enable support for more languages. |
Since 1.1.2 the default, coding highlighting and MIME-type processors support the argument lineno for adding line numbering to the code block. When a value is specified, as in lineno=3, the numbering will start at the specified value. When used in combination with the lineno argument, the marks argument is also supported for highlighting lines. A single line number, set of line numbers and range of line numbers are allowed. For example, marks=3, marks=3-6, marks=3,5,7 and marks=3-5,7 are all allowed. The specified values are relative to the numbered lines, so if lineno=2 is specified to start the line numbering at 2, marks=2 will result in the first line being highlighted.
Using the MIME type as processor, it is possible to syntax-highlight the same languages that are supported when browsing source code.
| MIME Type Processors | ||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Some examples: {{{#!text/html
<h1>text</h1>
}}}
| The result will be syntax highlighted HTML code: <h1>text</h1> The same is valid for all other mime types supported. | |||||||||||||||||||||||||||||||||||||||
{{{#!diff
--- Version 55
+++ Version 56
@@ -115,8 +115,9 @@
name='TracHelloWorld', version='1.0',
packages=find_packages(exclude=['*.tests*']),
- entry_points = """
- [trac.plugins]
- helloworld = myplugs.helloworld
- """,
+ entry_points = {
+ 'trac.plugins': [
+ 'helloworld = myplugs.helloworld',
+ ],
+ },
)
}}}
|
| |||||||||||||||||||||||||||||||||||||||
Line numbers can be added to code blocks and lines can be highlighted (since 1.1.2).
{{{#!python lineno=3 marks=3,9-10,16
def expand_markup(stream, ctxt=None):
"""A Genshi stream filter for expanding `genshi.Markup` events.
Note: Expansion may not be possible if the fragment is badly
formed, or partial.
"""
for event in stream:
if isinstance(event[1], Markup):
try:
for subevent in HTML(event[1]):
yield subevent
except ParseError:
yield event
else:
yield event
}}}
| Line | |
|---|---|
| 3 | def expand_markup(stream, ctxt=None): |
| 4 | """A Genshi stream filter for expanding `genshi.Markup` events. |
| 5 | |
| 6 | Note: Expansion may not be possible if the fragment is badly |
| 7 | formed, or partial. |
| 8 | """ |
| 9 | for event in stream: |
| 10 | if isinstance(event[1], Markup): |
| 11 | try: |
| 12 | for subevent in HTML(event[1]): |
| 13 | yield subevent |
| 14 | except ParseError: |
| 15 | yield event |
| 16 | else: |
| 17 | yield event |
For more processor macros developed and/or contributed by users, visit the Trac Hacks community site.
Processors are implemented using the same interfaces as Wiki macros, only the usage syntax differs. To develop a processor, see WikiMacros#DevelopingCustomMacros.
See also: WikiMacros, WikiHtml, WikiRestructuredText, TracSyntaxColoring, WikiFormatting, TracGuide
