Comment Plugin

Quickly post comments to a page without an edit/save cycle

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

Related topics: CommentPluginTemplates, 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.

Supports the definition of custom templates for prompts and for formatting what is placed into topics.

Supports custom access controls, allowing you to use it to add content to topics where the commenting user doesn't have CHANGE permissions.

Uses Javascript (if available) to ensure feedback is as rapid as possible.

Syntax

Write %COMMENT{attributes}% anywhere in a topic.

Parameters

• The following standard attributes are recognized

  Name	Description	Default
  type	This is the name of the template to use for this comment. Comment templates are defined in a Foswiki template - see Customisation, below. If this attribute is not defined, the type is whatever is defined by COMMENTPLUGIN_DEFAULT_TYPE preference setting.	below
  default	Default text to put into the prompt.
  target	Name of the topic to add the comment to	the current topic
  mode	For compatibility with older versions only, synonymous with type
  nonotify	Set to "on" to disable change notification for target topics	off
  noform	Set to "on" to disable the automatic form that is generated around your comment prompt if you don't provide a FORM template. See CommentPluginExamples:noform for an example.	off
  nopost	Set to "on" to disable insertion of the posted text into the topic.	off
  remove	Set to "on" to remove the comment prompt after the first time it is clicked.	off
  button	Button label text	Add comment

(See also 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 %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 an anchor

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

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

This uses a standard in-topic anchor as the insertion location. See EditingShorthand for more about Foswiki anchors.

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:

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

Customization

Customization of the comment plugin requires

• familiarity with HTML forms
• some familiarity with the Skin Templates.

To define a comment type, you have to provide at least 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 CommentPluginTemplate, which contains all the shipped standard templates and in turn includes System.UserCommentsTemplate that can include non-standard customizations.

This allows for several levels of customization:

1. To override all default templates, everywhere, change comments.tmpl to include a different topic (this customization will be lost next time you upgrade, though).
2. To add site-wide local template customizations, add them to 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.
3. To override templates on a web-by-web basis, add a topic UserCommentsTemplate to the web (this will replace System.UserCommentsTemplate)
4. To override templates for a specific skin, add them to System.UserComments<Skin>Template (where <Skin> is the name of the skin with the first letter capitalized, e.g. Pattern)

You can also define a comment template in a topic, by passing the topic location with templatetopic. For example:

%COMMENT{
   type="blogpost"
   templatetopic="BlogPostCommentTemplate"
   target="%TOPIC%"
   button="Add comment"
}%

templatetopic accepts topic or web.topic syntax. See an example in CommentPluginExamples:templatetopic.

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

Customization example

Provide both a PROMPT and an OUTPUT definition:

%TMPL:DEF{PROMPT:myComment}%%TMPL:P{promptbox}%%TMPL:END%
%TMPL:DEF{OUTPUT:myComment}%%TMPL:P{outputoneliner}%%POS:TOP%
%TMPL:END%

Call your custom comment with:

%COMMENT{type="myComment"}%

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.

The FORM template

The FORM template can optionally be provided if you want to explicitly define the form (the <form> and </form> tHTML ags) that wraps around the PROMPT template. If you don't define a FORM=template, one is automatically generated for you (unless the =noform="on" parameter is given).

Providing attribute values

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">

Special macros

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

Within a FORM definition, the body of the prompt is expanded to replace the %COMMENTPROMPT% macro.

EXPERT Note that when a comment is saved, the rest 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:

Note that comment_anchor overrides comment_index. Example, shows an "I Approve" button that adds your approval signature to the end of the topic:

<form method="post" action="%SCRIPTURL{restauth}%/CommentPlugin/comment" >
<input type="submit" value="I Approve" />
<input type="hidden" name="topic" value="%WEB%/%TOPIC%" />
<input type="hidden" name="redirectto" value="%WEB%/%TOPIC%" />
<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>

Customisation example with custom form template

This method has critical differences from the version shipped with Foswiki 1.1.4! (Identified by

)

Write a custom form in a topic.

• In the form, the action must be %SCRIPTURL{"rest"}%/CommentPlugin/comment. The save script used in previous versions will not work.
• In the form, the topic must be set to a valid, existing Web.Topic. topic is validated by the rest script which will reject the request if invalid.
• In the form, if the target topic will be provided by user input, use the comment_target input field to identify the target, otherwise it defaults to topic setting. comment_target is more flexible and can omit the Web part.
• In the form set the location of the prompt with %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:

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

Example comment:

%COMMENT{
   type="example"
   templatetopic="%SANDBOXWEB%.CommentPluginTemplateExample"
   target="%TOPIC%"
   button="Add comment"
}%

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 a subset of macros are 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.

The expanded variables are:

• %DATE% Signature-format date VarDATE
• %SERVERTIME% See VarSERVERTIME
• %GMTIME% See VarGMTIME
• %USERNAME% Base login name - VarUSERNAME
• %WIKINAME% Wiki name - VarWIKINAME
• %WIKIUSERNAME% Wiki name with prepended web - VarWIKIUSERNAME
• %URLPARAM{...}% - Parameters to the current CGI query - VarURLPARAM
• %NOP% No-op - VarNOP

All other Macros are inserted into the topic un-expanded and are expanded by standard rendering when the topic containing the comment is viewed.

In addition to Macros, there is one "token" expanded during output. $encodeguest will be set to "off" when the commenting user is logged in, and set to "entity" for anonymous comments. This is used in combination with the %URLPARAM% macro. Any user input from untrusted users should be entity encoded. For example:

%TMPL:DEF{outputoneliner}%   * %URLPARAM{"comment" encode="$encodeguest"}% -- %WIKIUSERNAME% - %GMTIME{"$day $month $year"}%%TMPL:END%

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:

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 macros that can be used in a topic template can also be used in an OUTPUT template.

Custom access controls

Using configure, the plugin can be configured to use a different access control domain than the default CHANGE. This allows you to use the plugin to add content to topics where the commenting user does not have CHANGE (or even VIEW) access.

Caution If you configure this plugin to use COMMENT permission instead of CHANGE, you should ensure that every web has the desired default permission by configuring ALLOWWEBCOMMENT or DENYWEBCOMMENT in every WebPreferences topic. You should also configure appropriate defaults in the _default Template web. If default permissions are not configured, then commenting will be permitted.

Settings

Two preference settings are recognised by the CommentPlugin:

These can be set in SitePreferences, in each web's WebPreferences, or in individual topics.

#Installation

Installation Instructions

You do not need to install anything in the browser to use this extension. The following instructions are for the administrator who installs the extension on the server.

Open configure, and open the "Extensions" section. "Extensions Operation and Maintenance" Tab -> "Install, Update or Remove extensions" Tab. Click the "Search for Extensions" button. Enter part of the extension name or description and press search. Select the desired extension(s) and click install. If an extension is already installed, it will not show up in the search results.

You can also install from the shell by running the extension installer as the web server user: (Be sure to run as the webserver user, not as root!)

cd /path/to/foswiki
perl tools/extension_installer <NameOfExtension> install

If you have any problems, or if the extension isn't available in configure, then you can still install manually from the command-line. See https://foswiki.org/Support/ManuallyInstallingExtensions for more help.

Note that if you want to use the action template then you must also:

1. Install the Foswiki:Extensions/ActionTrackerPlugin;
2. Put the CommentPlugin before the ActionTrackerPlugin in the {PluginsOrder} configuration option (in configure)

Upgrade Instructions

This plugin has been significantly changed from the 10 April 2011 version shipped with Foswiki 1.1.4.

• The plugin uses a rest handler to update topics. By default this script does not require authentication, and can now permit anonymous commenting. Examine the https://outzenj.com/bin/configure ( Security and Authentication tab, Login sub-tab ) configuration {AuthScripts} setting, and the scripts requiring authentication in the Apache configuration.
• The plugin no longer processes %COMMENT macros during save. If you have developed any forms using the noform and templatetopic examples they must be revised.

Change History