CommentPlugin < System

---+!! Comment Plugin

*Comment Plugin lets users quickly post comments to a page without an edit/preview/save cycle.*

%TOC{title="On this page:"}%

Related topics: CommentPluginTemplates, Sandbox.CommentPluginExamples

---++ Features

Inserts an edit box into the page that allows users to type in and save comments. Comments can be made
   * in different formats (as defined by a template),
   * in both forward and reverse chronological order,  
   * signed or unsigned, dated or undated (as defined by a template),
   * in other topics, or other positions within the current topic.

---++ Syntax
#StandardAttrs
Write =%<nop>COMMENT{<i>attributes</i>}%= anywhere in a topic.
%INCLUDE{"%SYSTEMWEB%.VarCOMMENT" section="comment_attributes"}%
(See also [[#MoreAttrs][additional attributes]])

---+++ Positioning the comment
=%COMMENT= supports several ways to specify _where_ a comment should be inserted in the target topic. This is referred to as the _location_ of the comment.

---++++ Location relative to <code>%COMMENT</code> tag
The default _location_ is the =%COMMENT= tag itself. For example:
<verbatim class="tml">
%COMMENT{type="below"}%
</verbatim>
will add comments in the current topic, directly below the =%COMMENT= tag.

---++++ Location relative to an anchor
The =target= attribute may specify a web, and may also specify an anchor within the target topic; for example, 
<verbatim class="tml">
%COMMENT{type="above" target="%MAINWEB%.PersonalRemarks#InsertHere"}%
</verbatim>
This uses a standard in-topic anchor as the insertion location. See %SYSTEMWEB%.TextFormattingRules for more about Foswiki anchors.

---++++ Location relative to an arbitrary text string
Getting more sophisticated, you can also specify a regular expression for the target location using the =location= parameter. The target topic is searched for the regular expression, and the comment inserted relative to the string that the search matched. For example,
<verbatim class="tml">
%COMMENT{type="above" location="Flights of Fancy"}%
</verbatim>
will place comments above the first occurence of the string =Flights of Fancy= in the current topic.

*Warning* of course, if a user's comment contains the string "Flights of Fancy" they may and up _changing the location_ for the next comment! Also, if you use a tag in the location, then you've just inserted another tag in the page that contains the =%COMMENT=! So be very careful how you specify the RE for =location=. Note that the RE is matched using perl "multiple line" mode, so ^ and $ match the start of a line and the end of a line respectively. %BR%
Also note that you cannot have the text =location="= just before the location.

I look forward to someone leveraging this feature to create - for example - threaded conversations using =%COMMENT=.

If you specify an anchor _and_ a =location=, the anchor will be ignored.

---+++ Default templates
Templates are used to define the "comment style" i.e. how comments appear in the page. The default is to add comments in "Blog like" style using bulleted lists, with the most recent comment at the top, but many other styles are available such as tables or Wiki thread mode comments. It is easy to define your own customer styles as well.

A set of default comment templates are shipped with the plugin - see also CommentPluginTemplates:
| *Template type* | *Description* |
| =top= | Comments, signed and dated (server time), added at top of the topic (the anchor is ignored) |
| =bottom= | Comments, signed and dated (server time), added at end of the target topic (the anchor is ignored) |
| =above= | Comments, signed and dated (server time), added immediately before the target anchor, or the =%COMMENT= if no anchor is specified |
| =below= | Comments, signed and dated (server time), added immediately below the target anchor, or the =%COMMENT= if no anchor is specified |
| =belowthreadmode= | Comments, signed and dated, added recurse after comment box |
| =threadmode= | Wiki thread mode comment, signed and dated (server time) |
| =tableprepend= | Comments, signed and dated (server time), formatted as an HTML table row, added below the anchor (which must be in an HTML &lt;table>) |
| =tableappend= | Comments, signed and dated (server time), formatted as an HTML table row, added above the anchor (which must be in an HTML &lt;table>) |
| =action= | Action added to action table directly above comment box (see <a href="#Installation">Plugin Installation Instructions</a> below for important notes) |
| =table= | Tablerows adding on end |
| =toctalk= | Talk using TOC adding on end |
| =bookmark= | Create a list of annotated bookmarks |
| =return= | Post to a different topic and return |

Your local installation may add more template types as well - see [[#TemPlates][Customisation]], below.

#TemPlates
---++ Customisation
Customisation of the comment plugin requires
   * familiarity with HTML forms
   * some familiarity with the [[%SYSTEMWEB%.SkinTemplates][Skin Templates]].

To define a comment type, you have to provide two simple template definitions in the template file; one for the prompt box, and one for the generated output. If we have a template type "mytype", these are named =PROMPT:mytype= and =OUTPUT:mytype= respectively. See =comments.tmpl= in the templates directory for examples.

The plugin picks up these template definitions from a standard template file, =templates/comments.tmpl=. This allows different templates to be defined for different Foswiki skins.

---+++ Defining custom templates
By default, =templates/comments.tmpl= includes the topic %SYSTEMWEB%.CommentPluginTemplate, which contains all the shipped standard templates and in turn includes %SYSTEMWEB%.<nop>UserCommentsTemplate that can include non-standard customisations.

This allows for several levels of customisation:
   1 To *override all default templates, everywhere*, change =comments.tmpl= to include a different topic (this customisation will be lost next time you upgrade, though).
   1 To add *site-wide local template customisations*, add them to %SYSTEMWEB%.UserCommentsTemplate (create if it does not exist yet). You can redefine the standard templates here if you want, and your definitions will override the standard definitions.
   1 To override templates on a *web-by-web basis*, add a topic =UserCommentsTemplate= to the web (this will replace %SYSTEMWEB%.<nop>UserCommentsTemplate)
   1 To override templates *for a specific skin*, add them to %SYSTEMWEB%.<nop>UserComments&lt;Skin&gt;Template (where &lt;Skin&gt; is the name of the skin with the first letter capitalised, e.g. Pattern)

You can also define a *comment template in a topic*, by passing the topic location with =templatetopic=. For example:
<blockquote>
<verbatim class="tml">
%COMMENT{
   type="blogpost"
   templatetopic="BlogPostCommentTemplate"
   target="%TOPIC%"
   button="Add comment"
}%
</verbatim>

=templatetopic= accepts =topic= or =web.topic= syntax. See an example in [[Sandbox.CommentPluginExamples#TemplateTopic][CommentPluginExamples:templatetopic]].
</blockquote>


<blockquote class="foswikiHelp"> %X% Templates are picked up by following the [[SkinTemplates#FindingTemplates][standard rules for locating template files]]. Note that you can use =%TMPL:INCLUDE= to include other files of templates.</blockquote>

---+++ Customisation example
Provide both a =PROMPT= and an =OUTPUT= definition:

<verbatim class="tml">
%TMPL:DEF{PROMPT:myComment}%%TMPL:P{promptbox}%%TMPL:END%
%TMPL:DEF{OUTPUT:myComment}%%TMPL:P{outputoneliner}%%POS:TOP%
%TMPL:END%
</verbatim>

Call your custom comment with:

<verbatim class="tml">
%COMMENT{type="myComment"}%
</verbatim>

---+++ The =PROMPT= template
The =PROMPT= template defines the contents of an HTML form that is used to capture the comment. This form invokes the comment generator when submitted. Parameters to the comment generator are defined using standard HTML input fields, such as =input=, =textarea= and =select=. The user enters values for these parameters, and these are then available when the =OUTPUT= template is expanded, in the form of <code>%<nop>URLPARAM%</code>s.

Only the input fields of the form need be defined. The plugin automatically generates the <code>&lt;form&gt;</code> and <code>&lt;/form&gt;</code> tags, unless you specify =noform="on"=, in which case you have to provide them yourself. *Note* that you must define a "submit" button if you want the form to work!

#MoreAttrs
---++++ Providing attribute values
If an attribute is given to the =%COMMENT= tag that is not one of the [[#StandardAttrs][standard attributes]], then that attribute is taken as the name of a parameter to be expanded in the =PROMPT= template. Expressions in the template of the form <code>%</code><i>param</i><code>|</code><i>default</i><code>%</code> (e.g. <code>%rows|3%</code>, <code>%button|Push me%</code>) are expanded to the values given in the <code>%COMMENT</code>. For example, if the =PROMPT= template 'example' contains:
<verbatim class="tml">
<textarea rows="%rows|3%" cols="%cols|50%" value="%tval|Rubbish%">
</verbatim>
and the %COMMENT tag is:
<verbatim class="tml">
%COMMENT{type="example" cols="75"}%
</verbatim>
then the template will be expanded as
<verbatim class="tml">
<textarea rows="3" cols="75" value="Rubbish">
</verbatim>

---++++ Special macros
As well as support for all the usual macros in templates, the following special macros are supported in the =PROMPT= definition:
    | *Macro* | *Description* |
    | =%<nop>DISABLED%= | Set to 'disabled' when you cannot comment (e.g. in preview mode). |
    | =%<nop>MESSAGE%= | The text specified by =default=. This may be overridden by a helpful message when the prompt is DISABLED. |

*EXPERT* Note that when a comment is saved, the =save= script is invoked on the target topic, with a number of parameters provided by the comment form. Normally the CommentPlugin will provide these fields in the form, but experts can also provide the fields themselves in order to get finer control over what is submitted, or you might want to define your own HTML forms that do comment submission. The parameters that the CommentPlugin recognises are as follows:
| *CGI parameter* | *Description* |
| =comment_action= | Must be =save= to get the CommentPlugin to perform |
| =comment_type= | Type of the OUTPUT template |
| =comment_index= | Zero-based index of the %COMMENT in the source topic. Used to place a post relative to an existing %COMMENT. |
| =comment_anchor= | Anchor taken from the =target= spec |
| =comment_location= | As passed to %COMMENT |
| =comment_nonotify= | As passed to %COMMENT |
| =comment_remove= | Zero-based index of a %COMMENT to remove from the target topic |
| =comment_nopost= | As passed to %COMMENT |
| =comment_templatetopic= | As passed to %COMMENT |
Note that =comment_location= overrides =comment_anchor=, and both override =comment_index=. Example, shows an "I Approve" button that adds your approval signature to the end of the topic:
<verbatim class="tml">
<form method="post" action="%SCRIPTURL{save}%/%WEB%/%TOPIC%">
<input type="submit" value="I Approve" />
<input type="hidden" name="comment_action" value="save" />
<input type="hidden" name="comment_type" value="bottom" />
<input type="hidden" name="comment" value="I Approve" />
</form>
</verbatim>

---++++ Customisation example with custom form template
Write a custom form in a topic.
   * In the form set the location of the prompt with =%<nop>COMMENTPROMPT%=; the prompt will be positioned here.
   * In %COMMENT use parameter =noform="on"=
   * In %COMMENT use parameter =templatetopic= to point to the topic with the form template

Example form:
<verbatim class="tml">
%TMPL:DEF{FORM:example}%
<form method="post" action="%SCRIPTURL{save}%/%BASEWEB%/%BASETOPIC%" enctype="application/x-www-form-urlencoded" name="examplecomment" id="examplecomment">
<input type="hidden" name="redirectto" value="%BASEWEB%.%BASETOPIC%" />
%COMMENTPROMPT%
</form>
%TMPL:END%
</verbatim>

Example comment:
<verbatim class="tml">
%COMMENT{
   noform="on"
   type="example"
   templatetopic="Sandbox.CommentPluginTemplateExample"
   target="%TOPIC%"
   button="Add comment"
}%
</verbatim>

---+++ The =OUTPUT= template
The =OUTPUT= template defines the format for the text that actually gets embedded into the topic. All the usual macros are available in the =PROMPT= definition, but note that they get expanded _when the comment is inserted in the text_, so time, date and username will refer to the time and date when the comment was made, and the user who made it.

There are also four position tags that are used to indicate where the comment should be placed, relative to the =location= defined in the =%COMMENT= tag:

    | =%<nop>POS:TOP%= | If present, comments will be inserted *at the top of the topic* i.e. before any other text |
    | =%<nop>POS:BOTTOM%= | If present, comments will be inserted *at the end of the topic* i.e. after all existing text |
    | =%<nop>POS:BEFORE%= | If present, comments will be inserted <b>immediately before the =%<nop>COMMENT%= tag</b> |
    | =%<nop>POS:AFTER%= | If present, comments will be inserted <b>immediately after the =%<nop>COMMENT%= tag</b> |
Note that these position tags are obviously mutually exclusive. If you define more than one, the result is undefined. If none is present, the default is taken from the plugin setting =DEFAULT_TYPE=

    | =%<nop>COMMENTPROMPT%= | Use with a custom form. If present, the comment prompt will be positioned here. |
    
All the [[TemplateTopics#TemplateTopicsVars][usual macros]] that can be used in a topic template can also be used in an =OUTPUT= template.

---++ Settings
<!-- Not used by the plugin
   * Set SHORTDESCRIPTION = Quickly post comments to a page without an edit/save cycle
%JQREQUIRE{"chili"}%
-->
Two [[%SYSTEMWEB%.PreferenceSettings][preference settings]] are recognised by the CommentPlugin:
| *Preference* | *Default* | *Description* |
| =%<nop>COMMENTPLUGIN_TEMPLATES%= | =comments= | Name of template file in the 'templates' directory that contains the comment templates. The default 'comments.tmpl' automatically includes user templates from %SYSTEMWEB%.CommentPluginTemplate, which in turn includes %SYSTEMWEB%.UserCommentsTemplate. |
| =%<nop>COMMENTPLUGIN_DEFAULT_TYPE%= | =above= | Default template type |
These can be set in !%USERSWEB%.SitePreferences, in !WebPreferences, or in individual topics.

#Installation
---++ Plugin Installation Instructions
   * This plugin is pre-installed in most releases. However if you need to upgrade the plugin for any reason:
   * Download the archive file from the Extensions web (see below)
   * Unpack the archive in your Foswiki installation directory.
      * You may need to correct file permissions
   * Run ==%TOPIC%_installer== to automatically check and install other modules that this module depends on, and enable the plugin.
   * Alternatively,
      * Manually resolve the dependencies listed below.
      None
   * Use =configure= to enable the plugin

Note that if you want to use the =action= template then you must also:
   1 Install the Foswiki:Extensions/ActionTrackerPlugin;
   1 Put the !CommentPlugin *before* the !ActionTrackerPlugin in the ={PluginsOrder}= configuration option (in =configure=)

---++ Plugin Info

Another great extension from the <a style="text-decoration:none" href="http://wikiring.com"><img src="%ATTACHURLPATH%/wikiringlogo20x20.png" alt="" /> *WikiRing* </a> - working together to improve your wiki experience!

|  Plugin Author: | Foswiki:Main.CrawfordCurrie http://www.c-dot.co.uk inspired by the work of TWiki:Main.DavidWeller and TWiki:Main.PeterMasiar |
|  Copyright: | &copy; 2004, Foswiki:Main.CrawfordCurrie<br />&copy; 2004-2010 Foswiki:%SYSTEMWEB%.ProjectContributor |
|  License: | GPL ([[http://www.gnu.org/copyleft/gpl.html][GNU General Public License]]) |
|  Release: | 21 Oct 2010 |
|  Version: | 9665 (2010-10-21) |
|  Change History: | |
|  21 Oct 2010 | Foswikitask:Item9857 - Restored the !CommentPluginTemplate to how it was before. All the changes done to make it look nice causes many errors. Never again add newlines, never again add trailing \ on existing templates. It does not always work. |
|  31 Jul 2010 | Foswikitask:Item9415 - Documentation updates |
|  27 May 2010 | Moved example topic Sandbox.CommentPluginExamples to Sandbox web. | 
|  24 Feb 2010 | Foswikitask:Item8611 - block comments resulting from calls to saveTopic from within an afterSaveHandler |
|  12 Sep 2009 | Foswikitask:Item8269 - Targeting anchors broken by Item727 is fixed. |
|  04 Jun 2009 | Foswikitask:Item1668 - The action template used with !ActionTrackerPlugin now uses new syntax ending with %ENDACTION. This makes each action item appear on a new line. Additionally new lines are now correctly saved as html br tags and not as html encoded br tag <br /> Foswikitask:Item1640 - Templates shipped with the plugin no longer encodes the user date entered when the date is saved so that it is possible for the user to use macros. |
|  15 Jan 2008 | Foswikitask:Item727 - data loss issue when missing anchor or location |
|  13 Jan 2009 | Foswikitask:Item736 - Make !CommentPlugin aware of CompareRevisionsAddOn bin script. |
|  16 Dec 2008 | Foswiki version |
|  06 Mar 2002 | initial commit |
|  Home: | http://foswiki.org/Extensions/%TOPIC% |
|  Support: | http://foswiki.org/Support/%TOPIC% |

*Related Topics:* %USERSWEB%.SitePreferences, [[%SYSTEMWEB%.Plugins][Plugins]]
This topic: System > Plugins > CommentPlugin
Topic revision: 04 Feb 2007, ProjectContributor (raw view)
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