Changes between Version 1 and Version 2 of WikiMacros


Ignore:
Timestamp:
07/07/13 01:26:40 (6 years ago)
Author:
trac
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • WikiMacros

    v1 v2  
    1 =  Wiki Macros = 
    2 Trac 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. 
     1= Trac Macros = 
    32 
    4 Another kind of macros are WikiProcessors. They typically deal with alternate markup formats and representation of larger blocks of information (like source code highlighting). See also: WikiProcessors. 
     3[[PageOutline]] 
     4 
     5Trac 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. Its syntax is `[[macro-name(optional-arguments)]]`. 
     6 
     7The WikiProcessors are another kind of macros. They typically deal with alternate markup formats and transformation of larger "blocks" of information (like source code highlighting). They are used for processing the multiline `{{{#!wiki-processor-name ... }}}` blocks. 
    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 parenthesis. 
    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. 
     12 
     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  }}} 
     31}}} 
     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. 
     54 
     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> 
     60}}} 
     61etc. 
     62}}} 
     63 
     64== Available Macros == 
     65 
     66''Note that the following list will only contain the macro documentation if you've not enabled `-OO` optimizations, or not set the `PythonOptimize` option for [wiki:TracModPython mod_python].'' 
     67 
     68[[MacroList]] 
     69 
     70== Macros from around the world == 
     71 
     72The [http://trac-hacks.org/ Trac Hacks] site provides a wide collection of macros and other Trac [TracPlugins plugins] contributed by the Trac community. If you're looking for new macros, or have written one that you'd like to share with the world, please don't hesitate to visit that site. 
     73 
     74== Developing Custom Macros == 
     75Macros, like Trac itself, are written in the [http://python.org/ Python programming language] and are developed as part of TracPlugins. 
     76 
     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. 
     86{{{ 
     87#!python 
     88from datetime import datetime 
     89# Note: since Trac 0.11, datetime objects are used internally 
     90 
     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')) 
     105}}} 
     106 
     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. 
     109{{{ 
     110#!python 
     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 
     144}}} 
     145 
     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''). 
     147 
     148For example, when writing: 
     149{{{ 
     150{{{#!HelloWorld style="polite" -silent verbose 
     151<Hello World!> 
     152}}} 
     153 
     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', 'silent': False, 'verbose': True} 
     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: 
    10170 
    11171{{{ 
    12  [[Timestamp]] 
     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()) 
    13185}}} 
    14 Display: 
    15  [[Timestamp]] 
    16  
    17 {{{ 
    18  [[HelloWorld(Testing)]] 
    19 }}} 
    20 Display: 
    21  [[HelloWorld(Testing)]] 
    22  
    23  
    24 == Available Macros == 
    25 Macros are still a new feature, and the list of available (and distributed) macros is 
    26 admittedly not very impressive. In future Trac releases, we hope to build a library of useful macros, and will of course happily include contributed macros (see below). 
    27  
    28  * '''!HelloWorld''' -- An example macro, useful for learning how to write macros. 
    29  * '''Timestamp''' -- Insert the current date and time. 
    30  
    31  
    32 ---- 
    33  
    34  
    35 == Macros from around the world == 
    36 The [http://projects.edgewall.com/trac/ Trac Project] has a section dedicated to user-contributed macros, [http://projects.edgewall.com/trac/wiki/MacroBazaar MacroBazaar]. If you're looking for new macros, or have written new ones to share with the world, don't hesitate adding it to the [http://projects.edgewall.com/trac/wiki/MacroBazaar MacroBazaar] wiki page. 
    37  
    38   http://projects.edgewall.com/trac/wiki/MacroBazaar 
    39  
    40  
    41 ---- 
    42  
    43  
    44 == Developing New Macros == 
    45 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 ''entry point'' function. Trac will display the returned data inserted into the HTML where the macro was called. 
    46  
    47 It's easiest to learn from an example: 
    48 {{{ 
    49 # MyMacro.py -- The world's simplest macro 
    50  
    51 def execute(hdf, args, env): 
    52     return "Hello World called with args: %s" % args 
    53 }}} 
    54  
    55 === Advanced Topics: Template-enabled Macros === 
    56 For advanced uses, macros can also render structured output in HDF, to be rendered to HTML using clearsilver templates - like most Trac output. In short, this allows more generic and well-designed advanced macros. 
    57  
    58 Macros gain direct access to the main HDF tree, and are free to manipulate it. 
    59  
    60 Example: 
    61 {{{ 
    62 def execute(hdf, args, env): 
    63     # Currently hdf is set only when the macro is called 
    64     # From a wiki page 
    65     if hdf: 
    66         hdf.setValue('wiki.macro.greeting', 'Hello World') 
    67  
    68     # args will be null if the macro is called without parentesis. 
    69     args = args or 'No arguments' 
    70     return 'Hello World, args = ' + args 
    71 }}} 
    72  
    73 You can also use the environment (env) object to access configuration data. 
    74  
    75 Example. 
    76 {{{ 
    77 def execute(hdf, txt, env): 
    78     return env.get_config('trac', 'repository_dir') 
    79 }}} 
    80 ---- 
    81 See also:  WikiProcessors, WikiFormatting, TracGuide