Comment Plugin

This plugin allows users to quickly post comments to a page without an edit/preview/save cycle.

( Discussion in TWiki:Plugins/CommentPluginDev )

Note: this version of the CommentPlugin will not work with TWiki versions released prior to June 2005

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 Rules

Write the command %COMMENT{ attributes }% anywhere in a TWiki topic. %COMMENT% is also legal.

The following attributes are recognised

Name	Description
type	This is the name of the template to use for this comment. Comment templates are defined in a TWiki template - see Customisation, below. If this attribute is not defined, the type is whatever is defined by COMMENTPLUGIN_DEFAULT_TYPE, either in this topic or in your WebPreferences. By default this is 'below'.
target	Name of the topic to add the comment to. Defaults to the current topic.
location	Regular expression specifying the comment location in the target topic. Read carefully below!
mode	For compatability with older versions only, synonymous with type
nonotify	Set to "on" to disable change notification for target topics
noform	Set to "on" to disable the automatic form that encloses your comment block - remember to insert <FORM> tags yourself!

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 %COMMENT tag

The default location is the %COMMENT tag itself. For example:

%COMMENT{type="below"}%

will add comments in the current topic, directly below the %COMMENT tag.

Location relative to a TWiki anchor

The target attribute may specify a web, and may also specify an anchor within the target topic; for example,

%COMMENT{type="above" target="%MAINWEB%.PersonalRemarks#InsertHere"}%

This uses a standard TWiki in-topic anchor as the insertion location. See TextFormattingRules for more about TWiki 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,

%COMMENT{type="above" location="Flights of Fancy"}%

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.

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. These are:

Template type	Description
top	Comments, signed and dated, added at top of the topic (the anchor is ignored)
bottom	Comments, signed and dated, added at end of the target topic (the anchor is ignored)
above	Comments, signed and dated, added immediately before the target anchor, or the %COMMENT if no anchor is specified
below	Comments, signed and dated, added immediately below the target anchor, or the %COMMENT if no anchor is specified
threadmode	Wiki thread mode comment, signed and dated
tableprepend	Comments, signed and dated, formatted as an HTML table row, added below the anchor (which must be in an HTML <table>)
tableappend	Comments, signed and dated, formatted as an HTML table row, added above the anchor (which must be in an HTML <table>)

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

Customisation

Customisation of the comment plugin requires

• familiarity with HTML forms,
• some familiarity with the TWiki templating language.

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 TWiki template file, templates/comments.tmpl. This allows different templates to be defined for different TWiki skins. By default, this template includes the topic CommentsTemplate, which contains all the shipped standard templates and in turn includes TWiki.UserCommentsTemplate. 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).
2. To add site-wide local template customisations, add them to TWiki.UserCommentTemplate. You can redefine the standard templates here if you want, and your definitions will override the standard definitions.
3. To override templates on a web-by-web basis, add a topic UserCommentTemplate to the web (this will replace TWiki.UserCommentTemplate)
4. To override templates for a specific skin, add them to TWiki.UserComment<Skin>Template (where <Skin> is the name of the skin with the first letter capitalised, e.g. Pattern)

Templates are picked up by following the standard TWiki rules for locating template files. Note that you can use %TMPL:INCLUDE to include other files of templates.

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 %URLPARAM%s.

Only the input fields of the form need be defined. The plugin automatically generates the >form< and &gt:/form< 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!

If an attribute is given to the %COMMENT tag that is not one of the 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 %param|default% (e.g. %rows|3%, %button|Push me%) are expanded to the values given in the %COMMENT. For example, if the PROMPT template 'example' contains:

<textarea rows=%rows|3% cols="%cols|50%" value="%tval|Rubbish%">

and the %COMMENT tag is:

%COMMENT{type="example" cols="75"}%

then the template will be expanded as

<textarea rows="3" cols="75" value="Rubbish">

As well as support for all the usual TWiki variables in templates, the following special variables are supported in the PROMPT definition:

Variable	Description
%MESSAGE%	A helpful generated message, either a lock message or a reminder to refresh.
%DISABLED%	Set to 'disabled' when you cannot comment (e.g. in preview mode).

The OUTPUT template

The OUTPUT template defines the format for the text that actually gets embedded into the topic. All the usual TWiki variables 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:

%POS:TOP%	If present, comments will be inserted at the top of the topic i.e. before any other text
%POS:BOTTOM%	If present, comments will be inserted at the end of the topic i.e. after all existing text
%POS:BEFORE%	If present, comments will be inserted immediately before the %COMMENT% tag
%POS:AFTER%	If present, comments will be inserted immediately after the %COMMENT% tag

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

All the usual TWikiVariables that can be used in a topic template can also be used in an OUTPUT template. See TWikiVariables for details.

Settings

• Description:
  • Set SHORTDESCRIPTION = Allows users to quickly post comments to a page without an edit/preview/save cycle.
• Name of file in the 'templates' directory that contains the comment templates. The default 'comments.tmpl' automatically includes user templates from CommentsTmpl^?
  • Set TEMPLATES = comments
• default template type (if not present, defaults to "below")
  • Set DEFAULT_TYPE = below

Plugin Installation Instructions

• This plugin is pre-installed in your TWiki release.

Plugin Info

Plugin Author:	v1.0 TWiki:Main.DavidWeller v2.0 TWiki:Main.PeterMasiar v3.0 TWiki:Main.CrawfordCurrie http://www.c-dot.co.uk
Change History:
1 Nov 2005	4.001 Revised template handling to allow for more generic customisation
22 Feb 2005	4.000 TWiki:Main.CrawfordCurrie made Dakar release ready. Recoded for new Plugins handlers, much more efficient. Removed TIME, now replaced by SERVERTIME.
25 Feb 2005	3.009 TWiki:Main.CrawfordCurrie Added Olivier Berger's fix for anchors and Jacob Eisinger's fix for variable expansion.
16 Oct 2004	3.008 Added the noform attribute to Comment - TWiki:Main.MartinCleaver
12 Oct 2004	3.007 TWiki:Main.CrawfordCurrie Disabled comment boxes in rdiff pane.
6 Oct 2004	3.006 TWiki:Main.CrawfordCurrie Fixed action template, which was expanded incorrectly. Upped default comment box to 70 chars default width.
16 Aug 2004	3.005 Cairo readiness; dependency checking; added threadmode template. TWiki:Main.CrawfordCurrie
11 Apr 2004	3.004 TWiki:Main.CrawfordCurrie fixed minor line termination problem fixed, and "security" hyphen on standard comment removed and replaced with a bulleted list.
6 April 2004	3.003 TWiki:Main.CrawfordCurrie Applied patches (thanks Peter Thoeny) for multiple comment adding, BOTTOM and TOP inside meta-data, and moved example to Sandbox.
13 March 2004	3.002 TWiki:Main.CrawfordCurrie Modified to use viewauth save technique (safer), add nonotify parameter, move templates fully into topics, with a hook for site specifics, support %COMMENT%, internationalisation fixes.
18 Feb 2004	3.001 TWiki:Main/CrawfordCurrie rewrote for standard templates and other user requests. Recognition to Patrice Fournier and Sam Abrams for terrific testing and patch support.
7 Feb 2004	TWiki:Main/CrawfordCurrie rewrote this page and CommentTemplates? in an effort to make the plugin more user friendly. Added {TIME} variable. Also updated CVS.
23 Sep 2003	2.000 TWiki:Main/PeterMasiar: 80% rewrite/refactor, adding templates
15 July 2003	TWiki:Main/PeterMasiar added "reminder" parameter and feature to pass comments to oopslockedcomments.tmpl template to copy-paste later
5 March 2002	Bug fixes, TWiki:Main/JonLambert created oopslockedcomments.tmpl template
24 Feb 2002	added a few more user requests, made "English" text configurable
4 Dec 2001	1.010 release, changed name to CommentPlugin, added $button var, changed textarea WRAP setting to "soft"
30 Nov 2001	1.000 Initial version
Dependencies:	Name Version Description TWiki::Contrib::Attrs >=1.000 Required. Download from TWiki:Plugins/AttrsContrib and install. TWiki::Plugins >=1.010 This plugin will not work with this TWiki version. It requires TWiki features introduced in Feb 2003 or later release.
Perl Version:	>= 5.6.1
Plugin Home:	TWiki:Plugins/CommentPlugin
Feedback:	TWiki:Plugins/CommentPluginDev

Related Topics: TWikiPreferences, TWikiPlugins