• 000011 by 193.254.61.19 on 2009/12/31 at 11:00 GMT
• 000004 by Yuri on 2007/06/24 at 20:59 GMT

Page Content

Each Sputnik<span class="teaser">
  pageSputnik requests supportsidentify a numbernode ofand "actions".  an Ifcommand to be sent by the node.  The node responds
  to the command by executing an action.  The mapping between commands and actions is defined
  by the node.
</span>

Each Sputnik node can perform actions in respond to commands.  (If you like, you can think of 
pages as "nouns" and actionscommands as "verbs"."verbs".) For instance, you can get this node to sent you its
raw representation by asking for:

    http://sputnik.freewisdom.org/en/Actions.raw

which consists of three parts:

    http://sputnik.freewisdom.org/en/
    Actions
    raw

This means:

1. Call the instance of Sputnik at "http://sputnik.freewisdom.org/en/"
2. Tell it to get the node called "Actions"
3. Tell it to send this node the command "raw"

If command is not specified, then it
assumed to be "show". So, the following two requests are equivalent:

    http://sputnik.freewisdom.org/en/Actions
    http://sputnik.freewisdom.org/en/Actions.show

What commands the node can understand and how it interprets them depends on the node.
Some nodes can understand commands that other nodes don't understand.  For instance,
the node [[Raw_Dot_File|Raw\_Dot\_File]], which contains a graph expressed in
GraphViz's "dot" format understands commands [[Raw_Dot_File.svg|svg]] and
[[Raw_Dot_File.png|png]].  Most
other nodes do not know how to respond to a "png" command.  Additionally, a node may
use interpret differently some of the standard actions.  For instance, most nodes
respond to "show" by running their content through [[Markdown]].  (This node does this.)
Nodes that contain Lua code (e.g., [[_navigation]]) do not do that: they display their
content as code instead.

## Defining actions

Each action is a function that takes three parameters and returns ancontent HTML(as stringa andstring) and
(optionally) a content type.  (If the action does not return a content type, it's assumed to 
be "text/html".)  TheIt three parameterscan are:

*also `page`set -some aattributes tableof thatthe node.  represents theThe three pageparameters (whichto the
is loadedaction function are:

and `decorated`* `node` before- itthe isnode passedspecified toby the action)request,
* `params``request` - a filtered[[WSAPI]] listrequest oftable, parameterspreprocessed passedby toSputnik theto unhash actionparameters,
* `sputnik` - athe tableinstance containingof additional"Sputnik" functionalitythat anis actiondispatching mightthe needrequest.

Here is a really simple action:

    actions.raw_content = function(page,function(node, params,request, sputnik)
       return page.content,node.content, "text/plain"
    end

Or a slightly more complicated one:

    actions.code = function(page,function(node, params,request, sputnik)
       page.inner_html = "<pre><code>" .. sputnik.escape(page.content)sputnik.escape(node.content)
          .. "</code></pre>"
       return page.wrappers.default(page,node.wrappers.default(node, params,request, sputnik)
    end

TheActions followingcan defaultbe actionsprovided in modules, which must all be in the "sputnik.actions" namespace for security reasons.  Sputnik comes with a default set areof providedactions, byprovided `sputnik_actions.lua`in modulethe and"sputnik.actions.wiki" module.  areIt includes loadedthe automatically:following action functions among others:

* `PAGE_NAME.show``show()` - display the page as HTML, with a navigation bar, etc.
* `PAGE_NAME.edit``edit()` - display the basic edit form for the page
* `PAGE_NAME.save``save()` - save the page (when submitted by the basicedit form)
* `PAGE_NAME.history``history()` - show page history
* `PAGE_NAME.diff``diff()` - show a diff from an earlier version
* `PAGE_NAME.show_inner``show_inner()` - display just the content part of HTML.HTML (no menus, etc.)
* `PAGE_NAME.edit_raw``raw()` - displayshow the formcontent that allows altering the underlying representation of the page
 *"as `PAGE_NAME.save_raw` -is" save- thein pageplain text

(when submitted## Mapping bycommands theto actions

"raw"Commands can form)
*be `PAGE_NAME.code`mapped -to showactions thein contentthe "actions" field of the pagenode "as is",or wrappedits [[Prototypes]].  in theThe default standardmappings HTMLlook (navas follows:

    bar,actions= [[
      etc.)
* `PAGE_NAME.raw` - show theshow  = "wiki.show"
      contentshow_content    = "wiki.show_content"
      ofhistory         = "wiki.history"
      theedit            = "wiki.edit"
      pagepost            = "wiki.post"
      "asrss             = "wiki.rss"
      is"diff            = "wiki.diff"
      -code            = "wiki.code"
      inraw             = "wiki.raw"
      plainraw_content     = "wiki.raw_content"
      text

login           = "wiki.show_login_form"
      Additional actions cansputnik_version = "wiki.sputnik_version"
      besave            = "wiki.save"
      providedpreview         = "wiki.preview"
      as modulespreview_content = "wiki.preview_content"
    prefixed with `sputnik_`]]

Configuration pages, andhowever, canoverride bethis loadedsetting bybecause setting"actions" theis `action`set parameteras offollows thein page:[[@Lua_Config]]:

    action={show="rss.rss"}

actions= In[[
      show_content="wiki.show_content_as_lua_code"
    ]]

This thismeans, case,that settingall thenodes `show`that actioninherit tofrom "rss.rss"@Lua_Config loadsrespond `sputnik_rss`to module"show_content" andby setsrunning `action.show``sputnik.actions.wiki.actions.show_content_as_lua_code()` toinstead theof `rss`the functionregular `sputnik.actions.wiki.actions.show_content()`.
defined by that module.