Changes between Version 1 and Version 2 of WikiMacros


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Timestamp:
Nov 27, 2011, 9:53:35 PM (13 years ago)
Author:
trac
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  • WikiMacros

    v1 v2  
    1 =  Wiki Macros =
     1= Trac Macros =
     2
     3[[PageOutline]]
     4
    25Trac macros are plugins to extend the Trac engine with custom 'functions' written in Python. A macro inserts dynamic HTML data in any context supporting WikiFormatting.
    36
     
    58
    69== Using Macros ==
    7 Macro calls are enclosed in two ''square brackets''. Like Python functions, macros can also have arguments, a comma separated list within parentheses.
    810
    9 === Examples ===
     11Macro calls are enclosed in two ''square brackets''. Like Python functions, macros can also have arguments, a comma separated list within parentheses.
    1012
    11 {{{
    12  [[Timestamp]]
     13=== Getting Detailed Help ===
     14The list of available macros and the full help can be obtained using the !MacroList macro, as seen [#AvailableMacros below].
     15
     16A brief list can be obtained via ![[MacroList(*)]] or ![[?]].
     17
     18Detailed help on a specific macro can be obtained by passing it as an argument to !MacroList, e.g. ![[MacroList(MacroList)]], or, more conveniently, by appending a question mark (?) to the macro's name, like in ![[MacroList?]].
     19
     20
     21
     22=== Example ===
     23
     24A list of 3 most recently changed wiki pages starting with 'Trac':
     25
     26||= Wiki Markup =||= Display =||
     27{{{#!td
     28  {{{
     29  [[RecentChanges(Trac,3)]]
     30  }}}
    1331}}}
    14 Display:
    15  [[Timestamp]]
     32{{{#!td style="padding-left: 2em;"
     33[[RecentChanges(Trac,3)]]
     34}}}
     35|-----------------------------------
     36{{{#!td
     37  {{{
     38  [[RecentChanges?(Trac,3)]]
     39  }}}
     40}}}
     41{{{#!td style="padding-left: 2em;"
     42[[RecentChanges?(Trac,3)]]
     43}}}
     44|-----------------------------------
     45{{{#!td
     46  {{{
     47  [[?]]
     48  }}}
     49}}}
     50{{{#!td style="padding-left: 2em"
     51{{{#!html
     52<div style="font-size: 80%" class="trac-macrolist">
     53<h3><code>[[Image]]</code></h3>Embed an image in wiki-formatted text.
    1654
    17 {{{
    18  [[HelloWorld(Testing)]]
     55The first argument is the file …
     56<h3><code>[[InterTrac]]</code></h3>Provide a list of known <a class="wiki" href="/wiki/InterTrac">InterTrac</a> prefixes.
     57<h3><code>[[InterWiki]]</code></h3>Provide a description list for the known <a class="wiki" href="/wiki/InterWiki">InterWiki</a> prefixes.
     58<h3><code>[[KnownMimeTypes]]</code></h3>List all known mime-types which can be used as <a class="wiki" href="/wiki/WikiProcessors">WikiProcessors</a>.
     59Can be …</div>
    1960}}}
    20 Display:
    21  [[HelloWorld(Testing)]]
     61etc.
     62}}}
    2263
    2364== Available Macros ==
     
    3273
    3374== Developing Custom Macros ==
    34 Macros, like Trac itself, are written in the [http://www.python.org/ Python programming language]. They are very simple modules, identified by the filename and should contain a single `execute()` function. Trac will display the returned data inserted into the HTML representation of the Wiki page where the macro is called.
     75Macros, like Trac itself, are written in the [http://python.org/ Python programming language] and are developed as part of TracPlugins.
    3576
    36 It's easiest to learn from an example:
     77For more information about developing macros, see the [trac:TracDev development resources] on the main project site.
     78
     79
     80Here are 2 simple examples showing how to create a Macro with Trac 0.11.
     81
     82Also, have a look at [trac:source:tags/trac-0.11/sample-plugins/Timestamp.py Timestamp.py] for an example that shows the difference between old style and new style macros and at the [trac:source:tags/trac-0.11/wiki-macros/README macros/README] which provides a little more insight about the transition.
     83
     84=== Macro without arguments ===
     85To test the following code, you should saved it in a `timestamp_sample.py` file located in the TracEnvironment's `plugins/` directory.
    3786{{{
    3887#!python
    39 # MyMacro.py -- The world's simplest macro
     88from datetime import datetime
     89# Note: since Trac 0.11, datetime objects are used internally
    4090
    41 def execute(hdf, args, env):
    42     return "Hello World called with args: %s" % args
     91from genshi.builder import tag
     92
     93from trac.util.datefmt import format_datetime, utc
     94from trac.wiki.macros import WikiMacroBase
     95
     96class TimeStampMacro(WikiMacroBase):
     97    """Inserts the current time (in seconds) into the wiki page."""
     98
     99    revision = "$Rev$"
     100    url = "$URL$"
     101
     102    def expand_macro(self, formatter, name, text):
     103        t = datetime.now(utc)
     104        return tag.b(format_datetime(t, '%c'))
    43105}}}
    44106
    45 You can also use the environment (`env`) object, for example to access configuration data and the database, for example:
     107=== Macro with arguments ===
     108To test the following code, you should saved it in a `helloworld_sample.py` file located in the TracEnvironment's `plugins/` directory.
    46109{{{
    47110#!python
    48 def execute(hdf, txt, env):
    49     return env.config.get('trac', 'repository_dir')
     111from genshi.core import Markup
     112
     113from trac.wiki.macros import WikiMacroBase
     114
     115class HelloWorldMacro(WikiMacroBase):
     116    """Simple HelloWorld macro.
     117
     118    Note that the name of the class is meaningful:
     119     - it must end with "Macro"
     120     - what comes before "Macro" ends up being the macro name
     121
     122    The documentation of the class (i.e. what you're reading)
     123    will become the documentation of the macro, as shown by
     124    the !MacroList macro (usually used in the WikiMacros page).
     125    """
     126
     127    revision = "$Rev$"
     128    url = "$URL$"
     129
     130    def expand_macro(self, formatter, name, text, args):
     131        """Return some output that will be displayed in the Wiki content.
     132
     133        `name` is the actual name of the macro (no surprise, here it'll be
     134        `'HelloWorld'`),
     135        `text` is the text enclosed in parenthesis at the call of the macro.
     136          Note that if there are ''no'' parenthesis (like in, e.g.
     137          [[HelloWorld]]), then `text` is `None`.
     138        `args` are the arguments passed when HelloWorld is called using a
     139        `#!HelloWorld` code block.
     140        """
     141        return 'Hello World, text = %s, args = %s' % \
     142            (Markup.escape(text), Markup.escape(repr(args)))
     143
    50144}}}
    51145
    52 Note that since version 0.9, wiki macros can also be written as TracPlugins. This gives them some capabilities that “classic” macros do not have, such as being able to directly access the HTTP request.
     146Note that `expand_macro` optionally takes a 4^th^ parameter ''`args`''. When the macro is called as a [WikiProcessors WikiProcessor], it's also possible to pass `key=value` [WikiProcessors#UsingProcessors processor parameters]. If given, those are stored in a dictionary and passed in this extra `args` parameter. On the contrary, when called as a macro, `args` is  `None`. (''since 0.12'').
    53147
    54 For more information about developing macros, see the [http://projects.edgewall.com/trac/wiki/TracDev development resources] on the main project site.
     148For example, when writing:
     149{{{
     150{{{#!HelloWorld style="polite"
     151<Hello World!>
     152}}}
    55153
    56 ----
    57 See also:  WikiProcessors, WikiFormatting, TracGuide
     154{{{#!HelloWorld
     155<Hello World!>
     156}}}
     157
     158[[HelloWorld(<Hello World!>)]]
     159}}}
     160One should get:
     161{{{
     162Hello World, text = <Hello World!> , args = {'style': u'polite'}
     163Hello World, text = <Hello World!> , args = {}
     164Hello World, text = <Hello World!> , args = None
     165}}}
     166
     167Note that the return value of `expand_macro` is '''not''' HTML escaped. Depending on the expected result, you should escape it by yourself (using `return Markup.escape(result)`) or, if this is indeed HTML, wrap it in a Markup object (`return Markup(result)`) with `Markup` coming from Genshi, (`from genshi.core import Markup`). 
     168
     169You can also recursively use a wiki Formatter (`from trac.wiki import Formatter`) to process the `text` as wiki markup, for example by doing:
     170
     171{{{
     172#!python
     173from genshi.core import Markup
     174from trac.wiki.macros import WikiMacroBase
     175from trac.wiki import Formatter
     176import StringIO
     177
     178class HelloWorldMacro(WikiMacroBase):
     179        def expand_macro(self, formatter, name, text, args):
     180                text = "whatever '''wiki''' markup you want, even containing other macros"
     181                # Convert Wiki markup to HTML, new style
     182                out = StringIO.StringIO()
     183                Formatter(self.env, formatter.context).format(text, out)
     184                return Markup(out.getvalue())
     185}}}