-A FEW NOTES ON THE PLUGIN ARCHITECTURE
-======================================
+$Id$
+
+In addition to this document, please check out the SquirrelMail
+development FAQ for more information. Also, help writing plugins
+is easily obtained by posting to the squirrelmail-plugins mailing
+list. (See details about mailing lists on the website)
-The plugin architecture of SquirrelMail is designed to make it
-possible to add new features without having to patch SquirrelMail
-itself. At the moment the plugin part of SquirrelMail should be
-considered "alpha" or "beta" quality code.
+FAQ -> http://www.squirrelmail.org/wiki/wiki.php?DeveloperFAQ
+Plugin Development ->
+ http://www.squirrelmail.org/wiki/wiki.php?DevelopingPlugins
-Until the functionality and code is more stable, be prepared for
-plugins to suddenly stop working.
-Functionality like password changing, displaying ads and calendars
-should be possible to add as plugins.
+A FEW NOTES ON THE PLUGIN ARCHITECTURE
+======================================
+The plugin architecture of SquirrelMail is designed to make it possible
+to add new features without having to patch SquirrelMail itself.
+Functionality like password changing, displaying ads and calendars should
+be possible to add as plugins.
-The idea
+
+The Idea
--------
The idea is to be able to run random code at given places in the
translations will be provided.
-The implementation
+The Implementation
------------------
-In the main SquirrelMail files the file functions/plugin.php. In
-places where hooks are made available they are executed by calling the
-function do_hook("hookname").
-
-The do_hook traverses the array $squirrelmail_plugin_hooks["hookname"]
-and executes all the functions that are named in that array.
+The plugin jumping off point in the main SquirrelMail code is in the
+file functions/plugin.php. In places where hooks are made available,
+they are executed by calling the function do_hook('hookname'). The
+do_hook function then traverses the array
+$squirrelmail_plugin_hooks['hookname'] and executes all the functions
+that are named in that array. Those functions are placed there when
+plugins register themselves with SquirrelMail as discussed below. A
+plugin may add its own internal functions to this array under any
+hook name provided by the SquirrelMail developers.
A plugin must reside in a subdirectory in the plugins/ directory. The
-name of the subdirectory is considered the name of the plugin.
+name of the subdirectory is considered to be the name of the plugin.
+(The plugin will not function correctly if this is not the case.)
To start using a plugin, its name must be added to the $plugins array
in config.php like this:
- $plugins[0] = "plugin_name";
+ $plugins[0] = 'plugin_name';
-When a plugin is registered the file plugins/plugin_name/setup.php is
-included and the function squirrelmail_plugin_init_plugin_name is
-called with no parameters.
+When a plugin is registered, the file plugins/plugin_name/setup.php is
+included and the function squirrelmail_plugin_init_plugin_name() is
+called with no parameters. That function is where the plugin may
+register itself against any hooks it wishes to take advantage of.
-Writing plugins
----------------
+WRITING PLUGINS
+===============
+
+All plugins must contain a file called setup.php and must include a
+function called squirrelmail_plugin_init_plugin_name() therein. Since
+including numerous plugins can slow SquirrelMail performance
+considerably, the setup.php file should contain little else. Any
+functions that are registered against plugin hooks should do little
+more than call another function in a different file.
-A plugin must consist of at least a file called setup.php. All other
-files the plugin consist of should also be in the plugin directory.
+Any other files used by the plugin should also be placed in the
+plugin directory (or subdirectory thereof) and should contain the
+bulk of the plugin logic.
-The function squirrelmail_plugin_init_plugin_name is called to
-initalize a plugin. This function could look something like this:
+The function squirrelmail_plugin_init_plugin_name() is called to
+initalize a plugin. This function could look something like this (if
+the plugin was named "demo" and resided in the directory plugins/demo/):
-function squirrelmail_plugin_init_demo () {
- global $squirrelmail_plugin_hooks;
+function squirrelmail_plugin_init_demo ()
+{
+ global $squirrelmail_plugin_hooks;
- $squirrelmail_plugin_hooks["generic_header"]["demo"] = "plugin_demo_header";
- $squirrelmail_plugin_hooks["menuline"]["demo"] = "plugin_demo_menuline";
+ $squirrelmail_plugin_hooks['generic_header']['demo'] = 'plugin_demo_header';
+ $squirrelmail_plugin_hooks['menuline']['demo'] = 'plugin_demo_menuline';
}
-Note that the SquirrelMail files assume that all other SquirrelMail
-files are available as ../directory/file. This means that if some file
-in the plugin directory is requested, it must do a chdir("..") before
-including any of the standard SquirrelMail files.
+Please note that as of SquirrelMail 1.5.0, this function will no longer
+be called at run time and will instead be called only once at configure-
+time. Thus, the inclusion of any dynamic code (anything except hook
+registration) here is strongly discouraged.
+
+In this example, the "demo" plugin should also have two other functions
+in its setup.php file called plugin_demo_header() and plugin_demo_menuline().
+The first of these might look something like this:
+
+function plugin_demo_header()
+{
+ include_once(SM_PATH . 'plugins/demo/functions.php');
+ plugin_demo_header_do();
+}
+
+The function called plugin_demo_header_do() would be in the file called
+functions.php in the demo plugin directory and would contain the plugin's
+core logic for the "generic_header" hook.
+
+
+Including Other Files
+---------------------
+
+A plugin may need to reference functionality provided in other
+files, and therefore need to include those files. Most of the
+core SquirrelMail functions are already available to your plugin
+unless it has any files that are requested directly by the client
+browser (custom options page, etc.). In this case, you'll need
+to make sure you include the files you need (see below).
+
+Note that as of SquirrelMail 1.4.0, all files are accessed using a
+constant called SM_PATH that always contains the relative path to
+the main SquirrelMail directory. This constant is always available
+for you to use when including other files from the SquirrelMail core,
+your own plugin, or other plugins, should the need arise. If any of
+your plugin files are requested directly from the client browser,
+you will need to define this constant before you do anything else:
+
+ define('SM_PATH', '../../');
+Files are included like this:
+
+ include_once(SM_PATH . 'include/validate.php');
+
+When including files, please make sure to use the include_once() function
+and NOT include(), require(), or require_once(), since these all are much
+less efficient than include_once() and can have a cumulative effect on
+SquirrelMail performance.
+
+The files that you may need to include in a plugin will vary greatly
+depending upon what the plugin is designed to do. For files that are
+requested directly by the client browser, we strongly recommend that
+you include the file include/validate.php, since it will set up the
+SquirrelMail environment automatically. It will ensure the the user
+has been authenticated and is currently logged in, load all user
+preferences, include internationalization support, call stripslashes()
+on all incoming data (if magic_quotes_gpc is on), and initialize and
+include all other basic SquirrelMail resources and functions. You may
+see other plugins that directly include other SquirrelMail files, but
+that is no longer necessary and is a hold-over from older SquirrelMail
+versions.
+
+
+Hook Types: Parameters and Return Values
+-----------------------------------------
-Hook Data Passed
-----------------
Hooks, when executed, are called with one parameter, an array of data
that is passed to the hook. The first element in the array is the name
of the hook that is being called. Any other elements in the array are
-dependant on the type of hook that is being called.
+dependant on the type of hook that is being called. Most hooks do not
+pass any other data, but be sure to check the hook you are using for
+any useful information it may provide. Generally speaking, in the case
+that any extra data is available here, your plugin should NOT change
+it unless you know what you are doing or it is documented otherwise.
+See below for further discussion of special hook types and the values
-Some of the information in the array may be changed. By default, the
-plugins should never change data unless it is documented otherwise.
+Most hooks, when executed, are called using the do_hook() function,
+where no return value is used. There are a limited number of hooks,
+however, that are called using the do_hook_function() and
+concat_hook_function() function calls. Both of these hook types may
+use the value returned by your plugin for its own purposes or to
+display in the resultant HTML output (you need to research the specific
+hook to determine its use). The do_hook_function() type hook will
+only use the return value it retrieves from the LAST plugin in the
+list of plugins registered against such a hook, whereas the
+concat_hook_function() type hook will concatenate the return values
+from all plugins that are registered against the hook and use that
+value (usually as a string of HTML code to output to the client).
-List of hooks
+List of Hooks
-------------
- generic_header functions/page_header.php
- menuline functions/page_header.php
- compose_button_row src/compose.php
- compose_bottom src/compose.php
- left_main_before src/left_main.php
- left_main_after src/left_main.php
- * options_save src/options.php (see note on options)
- * options_link_and_description src/options.php (see note on options)
- * options_highlight_bottom src/options_highlight.php
- * options_personal_bottom src/options_personal.php
- * options_personal_inside src/options_personal.php
- * options_personal_save src/options_personal.php
- * options_display_bottom src/options_display.php
- * options_display_inside src/options_display.php
- * options_display_save src/options_display.php
- * options_folders_bottom src/options_folders.php
- * options_folders_inside src/options_folders.php
- * options_folders_save src/options_folders.php
- logout src/signout.php
- login_before src/webmail.php
- login_verified src/webmail.php
- loading_prefs src/load_prefs.php
- mailbox_index_before functions/mailbox_display.php
- mailbox_index_after functions/mailbox_display.php
- mailbox_form_before functions/mailbox_display.php
- right_main_after_header src/right_main.php
- right_main_bottom src/right_main.php
- login_top src/login.php
- login_bottom src/login.php
- html_top src/read_body.php
- read_body_top src/read_body.php
- read_body_bottom src/read_body.php
- html_bottom src/read_body.php
- search_before_form src/search.php
- search_after_form src/search.php
- search_bottom src/search.php
- help_top src/help.php
- help_bottom src/help.php
- help_chapter src/help.php
- addrbook_html_search_below src/addrbook_search_html.php
- addressbook_bottom src/addressbook.php
- ^ attachment $type0/$type1 functions/mime.php (see note on attachments)
+
+This is a list of all hooks currently available in SquirrelMail, ordered
+by file. Note that this list is accurate as of June 17, 2003 (should be
+close to what is contained in release 1.4.1, plus or minus a hook or two),
+but may be out of date soon thereafter. You never know. ;-)
+
+ Hook Name Found In Called With(#)
+ --------- -------- --------------
+ loading_constants functions/constants.php do_hook
+ get_pref_override functions/file_prefs.php hook_func
+ get_pref functions/file_prefs.php hook_func
+ special_mailbox functions/imap_mailbox.php hook_func
+ % rename_or_delete_folder functions/imap_mailbox.php hook_func
+ msg_envelope functions/mailbox_display.php do_hook
+ mailbox_index_before functions/mailbox_display.php do_hook
+ mailbox_form_before functions/mailbox_display.php do_hook
+ mailbox_index_after functions/mailbox_display.php do_hook
+ check_handleAsSent_result functions/mailbox_display.php do_hook
+ subject_link functions/mailbox_display.php concat_hook
+ mailbox_display_buttons functions/mailbox_display.php do_hook
+ message_body functions/mime.php do_hook
+ ^ attachment $type0/$type1 functions/mime.php do_hook
+ attachments_bottom functions/mime.php hook_func
+ decode_body functions/mime.php hook_func
+ generic_header functions/page_header.php do_hook
+ menuline functions/page_header.php do_hook
+ internal_link functions/page_header.php hook_func
+ loading_prefs include/load_prefs.php do_hook
+ addrbook_html_search_below src/addrbook_search_html.php do_hook
+ addressbook_bottom src/addressbook.php do_hook
+ compose_form src/compose.php do_hook
+ compose_bottom src/compose.php do_hook
+ compose_button_row src/compose.php do_hook
+ compose_send src/compose.php do_hook
+ folders_bottom src/folders.php do_hook
+ help_top src/help.php do_hook
+ help_chapter src/help.php do_hook
+ help_bottom src/help.php do_hook
+ left_main_after_each_folder src/left_main.php concat_hook
+ left_main_before src/left_main.php do_hook
+ left_main_after src/left_main.php do_hook
+ create_collapse_link src/left_main.php hook_func
+ login_cookie src/login.php do_hook
+ login_top src/login.php do_hook
+ login_form src/login.php do_hook
+ login_bottom src/login.php do_hook
+ move_before_move src/move_messages.php do_hook
+ move_messages_button_action src/move_messages.php concat_hook
+ * optpage_set_loadinfo src/options.php do_hook
+ * optpage_loadhook_personal src/options.php do_hook
+ * optpage_loadhook_display src/options.php do_hook
+ * optpage_loadhook_highlight src/options.php do_hook
+ * optpage_loadhook_folder src/options.php do_hook
+ * optpage_loadhook_order src/options.php do_hook
+ * options_personal_save src/options.php do_hook
+ * options_display_save src/options.php do_hook
+ * options_folder_save src/options.php do_hook
+ * options_save src/options.php do_hook
+ * optpage_register_block src/options.php do_hook
+ * options_link_and_description src/options.php do_hook
+ * options_personal_inside src/options.php do_hook
+ * options_display_inside src/options.php do_hook
+ * options_highlight_inside src/options.php do_hook
+ * options_folder_inside src/options.php do_hook
+ * options_order_inside src/options.php do_hook
+ * options_personal_bottom src/options.php do_hook
+ * options_display_bottom src/options.php do_hook
+ * options_highlight_bottom src/options.php do_hook
+ * options_folder_bottom src/options.php do_hook
+ * options_order_bottom src/options.php do_hook
+ * options_highlight_bottom src/options_highlight.php do_hook
+ & options_identities_process src/options_identities.php do_hook
+ & options_identities_top src/options_identities.php do_hook
+ &% options_identities_renumber src/options_identities.php do_hook
+ & options_identities_table src/options_identities.php concat_hook
+ & options_identities_buttons src/options_identities.php concat_hook
+ message_body src/printer_friendly_bottom.php do_hook
+ read_body_header src/read_body.php do_hook
+ read_body_menu_top src/read_body.php do_hook
+ read_body_menu_bottom src/read_body.php do_hook
+ read_body_header_right src/read_body.php do_hook
+ html_top src/read_body.php do_hook
+ read_body_top src/read_body.php do_hook
+ read_body_bottom src/read_body.php do_hook
+ html_bottom src/read_body.php do_hook
+ login_before src/redirect.php do_hook
+ login_verified src/redirect.php do_hook
+ generic_header src/right_main.php do_hook
+ right_main_after_header src/right_main.php do_hook
+ right_main_bottom src/right_main.php do_hook
+ search_before_form src/search.php do_hook
+ search_after_form src/search.php do_hook
+ search_bottom src/search.php do_hook
+ logout src/signout.php do_hook
+ webmail_top src/webmail.php do_hook
+ webmail_bottom src/webmail.php do_hook
+ logout_above_text src/signout.php concat_hook
+% = This hook is used in multiple places in the given file
+# = Called with hook type (see below)
+& = Special identity hooks (see below)
+^ = Special attachments hook (see below)
+* = Special options hooks (see below)
+
+
+(#) Called With
+---------------
+Each hook is called using the hook type specified in the list above:
+ do_hook do_hook()
+ hook_func do_hook_function()
+ concat_hook concat_hook_function()
+
+
+(&) Identity Hooks
+------------------
+This set of hooks is passed special information in the array of arguments:
+
+options_identities_process
+
+ This hook is called at the top of the Identities page, which is
+ most useful when the user has changed any identity settings - this
+ is where you'll want to save any custom information you are keeping
+ for each identity or catch any custom submit buttons that you may
+ have added to the identities page. The arguments to this hook are:
+
+ [0] = hook name (always "options_identities_process")
+ [1] = should I run the SaveUpdateFunction() (alterable)
+
+ Obviously, set the second array element to 1/true if you want to
+ trigger SaveUpdateFunction() after the hook is finished - by default,
+ it will not be called.
+
+options_identities_renumber
+
+ This hook is called when one of the identities is being renumbered,
+ such as if the user had three identities and deletes the second -
+ this hook would be called with an array that looks like this:
+ ('options_identities_renumber', 2, 1). The arguments to this hook
+ are:
+
+ [0] = hook name (always "options_identities_renumber")
+ [1] = being renumbered from ('default' or 1 through (# idents) - 1)
+ [2] = being renumbered to ('default' or 1 through (# idents) - 1)
-(*) Options
------------
-There are two ways to do options for your plugin. First, you can incorporate it
-into an existing section of the preferences (Display, Personal, or Folders).
-The second way, you create your own section that they can choose from and it
-displays its own range of options.
+options_identities_table
+ This hook allows you to insert additional rows into the table that
+ holds each identity. The arguments to this hook are:
-First: Integrating into existing options
------------------------------------------
-There are two hooks you need to use for this one:
-
-1. options_YOUCHOOSE_inside
- This is the code that goes inside the table for the section you choose. Since
- it is going inside an existing table, it must be in this form:
- ------cut here-------
- <tr>
- <td>
- OPTION_NAME
- </td>
- <td>
- OPTION_INPUT
- </td>
- </tr>
- ------cut here-------
-
-2. options_YOUCHOOSE_save
- This is the code that saves your preferences into the users' preference
- file. For an example of how to do this, see src/options.php.
+ [0] = color of table (use it like this in your plugin:
+ <tr bgcolor="<?PHP echo $info[1]?>">
+ [1] = is this an empty section (the one at the end of the list)?
+ [2] = what is the 'post' value? (ident # or empty string if default)
-
-Second: Create your own section
--------------------------------
-It is possible to create your own options sections with plugins. There are
-three hooks you will need to use.
-
-1. options_link_and_description
- This creates the link and has a description that are shown on the options
- page. This should output HTML that looks like this:
-
- -----cut here-----
- function my_function() {
- global $color
- ?>
- <table width=50% cellpadding=3 cellspacing=0 border=0 align=center>
- <tr>
- <td bgcolor="<? echo $color[9] ?>">
- <a href="../plugins/YOUR_PLUGIN/YOUR_OPTIONS.php">YOUR OPTIONS NAME</a>
- </td>
- </tr>
- <tr>
- <td bgcolor="<? echo $color[0] ?>">
- YOUR DESCRIPTION
- </td>
- </tr>
- </table>
- <?php
+ You need to return any HTML you would like to add to the table.
+ You could add a table row with code similar to this:
+
+ function demo_identities_table(&$args)
+ {
+ return '<tr bgcolor="' . $args[0] . '"><td> </td><td>'
+ . 'YOUR CODE HERE' . '</td></tr>' . "\n";
}
- -----cut here-----
+
+options_identities_buttons
-2. options_save
- Here is the code that you need to do to save your options in the
- preference files or manipulate whatever data you are trying to change
- through the options section. You can look at options.php for details
- on how this is to be done.
+ This hook allows you to add a button (or other HTML) to the row of
+ buttons under each identity. The arguments to this hook are:
-3. loading_prefs (optional)
- If you are wanting to save preferences to the preference files, then
- you need to do this step as well. Otherwise if you are manipulating
- other data, ignore this step.
+ [0] = is this an empty section (the one at the end of the list)?
+ [1] = what is the 'post' value? (ident # or empty string if default)
- You should put the code in here that loads your preferences back
- into usable variables. Examples of this can be found in the file
- src/load_prefs.php
+ You need to return any HTML you would like to add here. You could add
+ a button with code similar to this:
+
+ function demo_identities_button(&$args)
+ {
+ return '<input type="submit" name="demo_button_' . $args[1]
+ . '" value="Press Me">';
+ }
(^) Attachment Hooks
When a message has attachments, this hook is called with the MIME types. For
instance, a .zip file hook is "attachment application/x-zip". The hook should
probably show a link to do a specific action, such as "Verify" or "View" for a
-.zip file.
+.zip file. Thus, to register your plugin for .zip attachments, you'd do this
+in setup.php (assuming your plugin is called "demo"):
+
+ $squirrelmail_plugin_hooks['attachment application/x-zip']['demo']
+ = 'demo_handle_zip_attachment';
This is a breakdown of the data passed in the array to the hook that is called:
[0] = Hook's name ('attachment text/plain')
- [1] = Array of links of actions (more below) (Alterable)
+ [1] = Array of links of actions (see below) (alterable)
[2] = Used for returning to mail message (startMessage)
[3] = Used for finding message to display (id)
[4] = Mailbox name, urlencode()'d (urlMailbox)
[5] = Entity ID inside mail message (ent)
- [6] = Default URL to go to when filename is clicked on (Alterable)
+ [6] = Default URL to go to when filename is clicked on (alterable)
[7] = Filename that is displayed for the attachment
[8] = Sent if message was found from a search (where)
[9] = Sent if message was found from a search (what)
To set up links for actions, you assign them like this:
- $Args[1]['your_plugin_name']['href'] = 'URL to link to';
- $Args[1]['your_plugin_name']['text'] = 'What to display';
+ $Args[1]['<plugin_name>']['href'] = 'URL to link to';
+ $Args[1]['<plugin_name>']['text'] = 'What to display';
+It's also possible to specify a hook as "attachment type0/*",
+for example "attachment text/*". This hook will be executed whenever there's
+no more specific rule available for that type.
+
+Putting all this together, the demo_handle_zip_attachment() function should
+look like this (note the argument being passed):
+
+ function demo_handle_zip_attachment(&$Args)
+ {
+ include_once(SM_PATH . 'plugins/demo/functions.php');
+ demo_handle_zip_attachment_do($Args);
+ }
+
+And the demo_handle_zip_attachment_do() function in the
+plugins/demo/functions.php file would typically (but not necessarily)
+display a custom link:
+
+ function demo_handle_zip_attachment_do(&$Args)
+ {
+ $Args[1]['demo']['href'] = SM_PATH . 'plugins/demo/zip_handler.php?'
+ . 'passed_id=' . $Args[3] . '&mailbox=' . $Args[4]
+ . '&passed_ent_id=' . $Args[5];
+ $Args[1]['demo']['text'] = 'show zip contents';
+ }
+
+The file plugins/demo/zip_handler.php can now do whatever it needs with the
+attachment (note that this will hand information about how to retrieve the
+source message from the IMAP server as GET varibles).
+
+
+(*) Options
+-----------
+Before you start adding user preferences to your plugin, please take a moment
+to think about it: in some cases, more options may not be a good thing.
+Having too many options can be confusing. Thinking from the user's
+perspective, will the proposed options actually be used? Will users
+understand what these options are for?
+
+There are two ways to add options for your plugin. When you only have a few
+options that don't merit an entirely new preferences page, you can incorporate
+them into an existing section of SquirrelMail preferences (Personal
+Information, Display Preferences, Message Highlighting, Folder Preferences or
+Index Order). Or, if you have an extensive number of settings or for some
+reason need a separate page for the user to interact with, you can create your
+own preferences page.
+
+
+Integrating Your Options Into Existing SquirrelMail Preferences Pages
+---------------------------------------------------------------------
+
+There are two ways to accomplish the integration of your plugin's settings
+into another preferences page. The first method is to add the HTML code
+for your options directly to the preferences page of your choice. Although
+currently very popular, this method will soon be deprecated, so avoid it
+if you can. That said, here is how it works. :) Look for any of the hooks
+named as "options_<pref page>_inside", where <pref page> is "display",
+"personal", etc. For this example, we'll use "options_display_inside" and,
+as above, "demo" as our plugin name:
+
+ 1. In setup.php in the squirrelmail_plugin_init_demo() function:
+
+ $squirrelmail_plugin_hooks['options_display_inside']['demo']
+ = 'demo_show_options';
+
+ Note that there are also hooks such as "options_display_bottom",
+ however, they place your options at the bottom of the preferences
+ page, which is usually not desirable (mostly because they also
+ come AFTER the HTML FORM tag is already closed). It is possible
+ to use these hooks if you want to create your own FORM with custom
+ submission logic.
+
+ 2. Assuming the function demo_show_options() calls another function
+ elsewhere called demo_show_options_do(), that function should have
+ output similar to this (note that you will be inserting code into
+ a table that is already defined with two columns, so please be sure
+ to keep this framework in your plugin):
+
+ ------cut here-------
+ <tr>
+ <td>
+ OPTION_NAME
+ </td>
+ <td>
+ OPTION_INPUT
+ </td>
+ </tr>
+ ------cut here-------
+
+ Of course, you can place any text where OPTION_NAME is and any input
+ tags where OPTION_INPUT is.
+
+ 3. You will want to use the "options_<pref page>_save" hook (in this case,
+ "options_display_save") to save the user's settings after they have
+ pressed the "Submit" button. Again, back in setup.php in the
+ squirrelmail_plugin_init_demo() function:
+
+ $squirrelmail_plugin_hooks['options_display_save']['demo']
+ = 'demo_save_options';
+
+ 4. Assuming the function demo_save_options() calls another function
+ elsewhere called demo_save_options_do(), that function should put
+ the user's settings into permanent storage (see the preferences
+ section below for more information). This example assumes that
+ in the preferences page, the INPUT tag's NAME attribute was set
+ to "demo_option":
+
+ global $data_dir, $username;
+ sqgetGlobalVar('demo_option', $demo_option);
+ setPref($data_dir, $username, 'demo_option', $demo_option);
+
+
+The second way to add options to one of the SquirrelMail preferences page is
+to use one of the "optpage_loadhook_<pref page>" hooks. The sent_subfolders
+plugin is an excellent example of this method. Briefly, this way of adding
+options consists of adding some plugin-specific information to a predefined
+data structure which SquirrelMail then uses to build the HTML input forms
+for you. This is the preferred method of building options lists going forward.
+
+ 1. We'll use the "optpage_loadhook_display" hook to add a new group of
+ options to the display preferences page. In setup.php in the
+ squirrelmail_plugin_init_demo() function:
+
+ $squirrelmail_plugin_hooks['optpage_loadhook_display']['demo']
+ = 'demo_options';
+
+ 2. Assuming the function demo_options() calls another function elsewhere
+ called demo_options_do(), that function needs to add a new key to two
+ arrays, $optpage_data['grps'] and $optpage_data['vals']. The value
+ associated with that key should simply be a section heading for your
+ plugin on the preferences page for the $optpage_data['grps'] array,
+ and yet another array with all of your plugin's options for the
+ $optpage_data['vals'] array. The options are built as arrays (yes,
+ that's four levels of nested arrays) that specify attributes that are
+ used by SquirrelMail to build your HTML input tags automatically.
+ This example includes just one input element, a SELECT (drop-down)
+ list:
+
+ global $optpage_data;
+ $optpage_data['grps']['DEMO_PLUGIN'] = 'Demo Options';
+ $optionValues = array();
+ $optionValues[] = array(
+ 'name' => 'plugin_demo_favorite_color',
+ 'caption' => 'Please Choose Your Favorite Color',
+ 'type' => SMOPT_TYPE_STRLIST,
+ 'refresh' => SMOPT_REFRESH_ALL,
+ 'posvals' => array(0 => 'red',
+ 1 => 'blue',
+ 2 => 'green',
+ 3 => 'orange'),
+ 'save' => 'save_plugin_demo_favorite_color'
+ );
+ $optpage_data['vals']['DEMO_PLUGIN'] = $optionValues;
+
+ The array that you use to specify each plugin option has the following
+ possible attributes:
+
+ name The name of this setting, which is used not only for
+ the INPUT tag name, but also for the name of this
+ setting in the user's preferences
+ caption The text that prefaces this setting on the preferences
+ page
+ type The type of INPUT element, which should be one of:
+ SMOPT_TYPE_STRING String/text input
+ SMOPT_TYPE_STRLIST Select list input
+ SMOPT_TYPE_TEXTAREA Text area input
+ SMOPT_TYPE_INTEGER Integer input
+ SMOPT_TYPE_FLOAT Floating point number input
+ SMOPT_TYPE_BOOLEAN Boolean (yes/no radio buttons)
+ input
+ SMOPT_TYPE_HIDDEN Hidden input (not actually
+ shown on preferences page)
+ SMOPT_TYPE_COMMENT Text is shown (specified by the
+ 'comment' attribute), but no
+ user input is needed
+ SMOPT_TYPE_FLDRLIST Select list of IMAP folders
+ refresh Indicates if a link should be shown to refresh part or
+ all of the window (optional). Possible values are:
+ SMOPT_REFRESH_NONE No refresh link is shown
+ SMOPT_REFRESH_FOLDERLIST Link is shown to refresh
+ only the folder list
+ SMOPT_REFRESH_ALL Link is shown to refresh
+ the entire window
+ initial_value The value that should initially be placed in this
+ INPUT element
+ posvals For select lists, this should be an associative array,
+ where each key is an actual input value and the
+ corresponding value is what is displayed to the user
+ for that list item in the drop-down list
+ value Specify the default/preselected value for this option
+ input
+ save You may indicate that special functionality needs to be
+ used instead of just saving this setting by giving the
+ name of a function to call when this value would
+ otherwise just be saved in the user's preferences
+ size Specifies the size of certain input items (typically
+ textual inputs). Possible values are:
+ SMOPT_SIZE_TINY
+ SMOPT_SIZE_SMALL
+ SMOPT_SIZE_MEDIUM
+ SMOPT_SIZE_LARGE
+ SMOPT_SIZE_HUGE
+ SMOPT_SIZE_NORMAL
+ comment For SMOPT_TYPE_COMMENT type options, this is the text
+ displayed to the user
+ script This is where you may add any additional javascript
+ or other code to the user input
+ post_script You may specify some script (usually Javascript) that
+ will be placed after (outside of) the INPUT tag.
+
+ 3. If you indicated a 'save' attribute for any of your options, you must
+ create that function (you'll only need to do this if you need to do
+ some special processing for one of your settings). The function gets
+ one parameter, which is an object with mostly the same attributes you
+ defined when you made the option above... the 'new_value' (and possibly
+ 'value', which is the current value for this setting) is the most useful
+ attribute in this context:
+
+ function save_plugin_demo_favorite_color($option)
+ {
+ // if user chose orange, make note that they are really dumb
+ if ($option->new_value == 3)
+ {
+ // more code here as needed
+ }
+
+ // don't even save this setting if user chose green (old
+ // setting will remain)
+ if ($option->new_value == 2)
+ return;
+
+ // for all other colors, save as normal
+ save_option($option);
+ }
+
+
+Creating Your Own Preferences Page
+----------------------------------
+
+It is also possible to create your own preferences page for a plugin. This
+is particularly useful when your plugin has numerous options or needs to
+offer special interaction with the user (for things such as changing password,
+etc.). Here is an outline of how to do so (again, using the "demo" plugin
+name):
+
+ 1. Add a new listing to the main Options page. Older versions of
+ SquirrelMail offered a hook called "options_link_and_description"
+ although its use is deprecated (and it is harder to use in that
+ it requires you to write your own HTML to add the option). Instead,
+ you should always use the "optpage_register_block" hook where you
+ create a simple array that lets SquirrelMail build the HTML
+ to add the plugin options entry automatically. In setup.php in the
+ squirrelmail_plugin_init_demo() function:
+
+ $squirrelmail_plugin_hooks['optpage_register_block']['demo']
+ = 'demo_options_block';
+
+ 2. Assuming the function demo_options_block() calls another function
+ elsewhere called demo_options_block_do(), that function only needs
+ to create a simple array and add it to the $optpage_blocks array:
+
+ global $optpage_blocks;
+ $optpage_blocks[] = array(
+ 'name' => 'Favorite Color Settings',
+ 'url' => SM_PATH . 'plugins/demo/options.php',
+ 'desc' => 'Change your favorite color & find new exciting colors',
+ 'js' => FALSE
+ );
+
+ The array should have four elements:
+ name The title of the plugin's options as it will be displayed on
+ the Options page
+ url The URI that points to your plugin's custom preferences page
+ desc A description of what the preferences page offers the user,
+ displayed on the Options page below the title
+ js Indicates if this option page requires the client browser
+ to be Javascript-capable. Should be TRUE or FALSE.
+
+ 3. There are two different ways to create the actual preferences page
+ itself. One is to simply write all of your own HTML and other
+ interactive functionality, while the other is to define some data
+ structures that allow SquirrelMail to build your user inputs and save
+ your data automatically.
+
+ Building your own page is wide open, and for ideas, you should look at
+ any of the plugins that currently have their own preferences pages. If
+ you do this, make sure to read step number 4 below for information on
+ saving settings. In order to maintain security, consistant look and
+ feel, internationalization support and overall integrity, there are just
+ a few things you should always do in this case: define the SM_PATH
+ constant, include the file include/validate.php (see the section about
+ including other files above) and make a call to place the standard page
+ heading at the top of your preferences page. The top of your PHP file
+ might look something like this:
+
+ define('SM_PATH', '../../');
+ include_once(SM_PATH . 'include/validate.php');
+ global $color;
+ displayPageHeader($color, 'None');
+
+ From here you are on your own, although you are encouraged to do things
+ such as use the $color array to keep your HTML correctly themed, etc.
+
+ If you want SquirrelMail to build your preferences page for you,
+ creating input forms and automatically saving users' settings, then
+ you should change the 'url' attribute in the options block you created
+ in step number 2 above to read as follows:
+
+ 'url' => SM_PATH . 'src/options.php?optpage=plugin_demo',
+
+ Now, you will need to use the "optpage_set_loadinfo" hook to tell
+ SquirrelMail about your new preferences page. In setup.php in the
+ squirrelmail_plugin_init_demo() function:
+
+ $squirrelmail_plugin_hooks['optpage_set_loadinfo']['demo']
+ = 'demo_optpage_loadinfo';
+
+ Assuming the function demo_optpage_loadinfo() calls another function
+ elsewhere called demo_optpage_loadinfo_do(), that function needs to
+ define values for four variables (make sure you test to see that it
+ is your plugin that is being called by checking the GET variable you
+ added to the url just above):
+
+ global $optpage, $optpage_name, $optpage_file,
+ $optpage_loader, $optpage_loadhook;
+ if ($optpage == 'plugin_demo')
+ {
+ $optpage_name = "Favorite Color Preferences";
+ $optpage_file = SM_PATH . 'plugins/demo/options.php';
+ $optpage_loader = 'load_optpage_data_demo';
+ $optpage_loadhook = 'optpage_loadhook_demo';
+ }
+
+ Now you are ready to build all of your options. In the file you
+ indicated for the variable $optpage_file above, you'll need to create
+ a function named the same as the value you used for $optpage_loader
+ above. In this example, the file plugins/demo/options.php should
+ have at least this function in it:
+
+ function load_optpage_data_demo()
+ {
+ $optpage_data = array();
+ $optpage_data['grps']['DEMO_PLUGIN'] = 'Demo Options';
+ $optionValues = array();
+ $optionValues[] = array(
+ 'name' => 'plugin_demo_favorite_color',
+ 'caption' => 'Please Choose Your Favorite Color',
+ 'type' => SMOPT_TYPE_STRLIST,
+ 'refresh' => SMOPT_REFRESH_ALL,
+ 'posvals' => array(0 => 'red',
+ 1 => 'blue',
+ 2 => 'green',
+ 3 => 'orange'),
+ 'save' => 'save_plugin_demo_favorite_color'
+ );
+ $optpage_data['vals']['DEMO_PLUGIN'] = $optionValues;
+ return $optpage_data;
+ }
+
+ For a detailed description of how you build these options, please read
+ step number 2 for the second method of adding options to an existing
+ preferences page above. Notice that the only difference here is in the
+ very first and last lines of this function where you are actually
+ creating and returning the options array instead of just adding onto it.
+
+ That's all there is to it - SquirrelMail will create a preferences page
+ titled as you indicated for $optpage_name above, and other plugins
+ can even add extra options to this new preferences page. To do so,
+ they should use the hook name you specified for $optpage_loadhook above
+ and use the second method for adding option settings to existing
+ preferences pages described above.
+
+ 4. Saving your options settings: if you used the second method in step
+ number 3 above, your settings will be saved automatically (or you can
+ define special functions to save special settings such as the
+ save_plugin_demo_favorite_color() function in the example described
+ above) and there is probably no need to follow this step. If you
+ created your own preferences page from scratch, you'll need to follow
+ this step. First, you need to register your plugin against the
+ "options_save" hook. In setup.php in the squirrelmail_plugin_init_demo()
+ function:
+
+ $squirrelmail_plugin_hooks['options_save']['demo']
+ = 'demo_save_options';
+
+ Assuming the function demo_save_options() calls another function
+ elsewhere called demo_save_options_do(), that function needs to grab
+ all of your POST and/or GET settings values and save them in the user's
+ preferences (for more about preferences, see that section below). Since
+ this is a generic hook called for all custom preferences pages, you
+ should always set "optpage" as a POST or GET variable with a string that
+ uniquely identifies your plugin:
+
+ <input type="hidden" name="optpage" value="plugin_demo">
+
+ Now in your demo_save_options_do() function, do something like this:
+
+ global $username, $data_dir, $optpage, $favorite_color;
+ if ($optpage == 'plugin_demo')
+ {
+ sqgetGlobalVar('favorite_color', $favorite_color, SQ_FORM);
+ setPref($data_dir, $username, 'favorite_color', $favorite_color);
+ }
+
+ Note that $favorite_color may not need to be globalized, although
+ experience has shown that some versions of PHP don't behave as expected
+ unless you do so. Even when you use SquirrelMail's built-in preferences
+ page generation functionality, you may still use this hook, although
+ there should be no need to do so. If you need to do some complex
+ validation routines, note that it might be better to do so in the file
+ you specified as the "$optpage_file" (in our example, that was the
+ plugins/demo/options.php file), since at this point, you can still
+ redisplay your preferences page. You could put code similar to this
+ in the plugins/demp/options.php file (note that there is no function;
+ this code needs to be executed at include time):
+
+ global $optmode;
+ if ($optmode == 'submit')
+ {
+ // do something here such as validation, etc
+ if (you want to redisplay your preferences page)
+ $optmode = '';
+ }
+
+
+Preferences
+-----------
+
+Saving and retrieving user preferences is very easy in SquirrelMail.
+SquirrelMail supports preference storage in files or in a database
+backend, however, the code you need to write to manipulate preferences
+is the same in both cases.
+
+Setting preferences:
+
+ Setting preferences is done for you if you use the built-in facilities
+ for automatic options construction and presentation (see above). If
+ you need to manually set preferences, however, all you need to do is:
+
+ global $data_dir, $username;
+ setPref($data_dir, $username, 'pref_name', $pref_value);
+
+ Where "pref_name" is the key under which the value will be stored
+ and "pref_value" is a variable that should contain the actual
+ preference value to be stored.
+
+Loading preferences:
+
+ There are two approaches to retrieving plugin (or any other) preferences.
+ You can grab individual preferences one at a time or you can add your
+ plugin's preferences to the routine that loads up user preferences at
+ the beginning of each page request. If you do the latter, making sure
+ to place your preference variables into the global scope, they will be
+ immediately available in all other plugin code. To retrieve a single
+ preference value at any time, do this:
+
+ global $data_dir, $username;
+ $pref_value = getPref($data_dir, $username, 'pref_name', 'default value');
+
+ Where "pref_name" is the preference you are retrieving, "default_value"
+ is what will be returned if the preference is not found for this user,
+ and, of course, "pref_value" is the variable that will get the actual
+ preference value.
+
+ To have all your preferences loaded at once when each page request is
+ made, you'll need to register a function against the "loading_prefs" hook.
+ For our "demo" plugin, in setup.php in the squirrelmail_plugin_init_demo()
+ function:
+
+ $squirrelmail_plugin_hooks['loading_prefs']['demo']
+ = 'demo_load_prefs';
+
+ Assuming the function demo_load_prefs() calls another function
+ elsewhere called demo_load_prefs_do(), that function just needs to
+ pull out any all all preferences you'll be needing elsewhere:
+
+ global $data_dir, $username, $pref_value;
+ $pref_value = getPref($data_dir, $username, 'pref_name', 'default value');
+
+ Remember to globalize each preference, or this code is useless.
+
+
+Internationalization
+--------------------
+
+Although this document may only be available in English, we sure hope that you
+are thinking about making your plugin useful to the thousands of non-English
+speaking SquirrelMail users out there! It is almost rude not to do so, and
+it isn't much trouble, either. This document will only describe how you can
+accomplish the internationalization of a plugin. For more general information
+about PHP and SquirrelMail translation facilities, see:
+
+http://www.squirrelmail.org/wiki/wiki.php?LanguageTranslation
+
+The unofficial way to internationalize a plugin is to put all plugin output
+into the proper format but to rely on the SquirrelMail translation facilities
+for all the rest. If the plugin were really to get translated, you'd need
+to make sure that all output strings for your plugin are either added to or
+already exist in the main SquirrelMail locale files.
+
+The better way to make sure your plugin is translated is to create your own
+locale files and what is called a "gettext domain" (see the link above for
+more information).
+
+There are three basic steps to getting your plugins internationalized: put
+all output into the proper format, switch gettext domains and create locale
+files.
+
+ 1. Putting plugin output into the correct format is quite easy. The hard
+ part is making sure you catch every last echo statement. You need to
+ echo text like this:
+
+ echo _("Hello");
+
+ So, even in the HTML segments of your plugin files, you need to do this:
+
+ <input type="submit" value="<?php echo _("Submit") ?>">
+
+ You can put any text you want inside of the quotes (you MUST use double
+ quotes!), including HTML tags, etc. What you should think carefully
+ about is that some languages may use different word ordering, so this
+ might be problematic:
+
+ echo _("I want to eat a ") . $fruitName . _(" before noon");
+
+ Because some languages (Japanese, for instance) would need to translate
+ such a sentence to "Before noon " . $fruitName . " I want to eat", but
+ with the format above, they are stuck having to translate each piece
+ separately. You might want to reword your original sentence:
+
+ echo _("This is what I want to eat before noon: ") . $fruitName;
+
+ 2. By default, the SquirrelMail gettext domain is always in use. That
+ means that any text in the format described above will be translated
+ using the locale files found in the main SquirrelMail locale directory.
+ Unless your plugin produces no output or only output that is in fact
+ translated under the default SquirrelMail domain, you need to create
+ your own gettext domain. The PHP for doing so is very simple. At
+ the top of any file that produces any output, place the following code
+ (again, using "demo" as the plugin name):
+
+ bindtextdomain('demo', SM_PATH . 'plugins/demo/locale');
+ textdomain('demo');
+
+ Now all output will be translated using your own custom locale files.
+ Please be sure to switch back to the SquirrelMail domain at the end
+ of the file, or many of the other SquirrelMail files may misbehave:
+
+ bindtextdomain('squirrelmail', SM_PATH . 'locale');
+ textdomain('squirrelmail');
+
+ Note that if, in the middle of your plugin file, you use any
+ SquirrelMail functions that send output to the browser, you'll need
+ to temporarily switch back to the SquirrelMail domain:
+
+ bindtextdomain('squirrelmail', SM_PATH . 'locale');
+ textdomain('squirrelmail');
+ displayPageHeader($color, 'None');
+ bindtextdomain('demo', SM_PATH . 'plugins/demo/locale');
+ textdomain('demo');
+
+ Note that technically speaking, you only need to have one bindtextdomain
+ call per file, you should always use it before every textdomain call,
+ since PHP installations without gettext compiled into them will not
+ function properly if you do not.
+
+ 3. Finally, you just need to create your own locale. You should create
+ a directory structure like this in the plugin directory:
+
+ demo
+ |
+ ------locale
+ |
+ ------de_DE
+ | |
+ | ------LC_MESSAGES
+ |
+ ------ja_JP
+ |
+ ------LC_MESSAGES
+
+ Create a directories such as de_DE for each language (de_DE is German,
+ ja_JP is Japanese, etc. - check the SquirrelMail locale directory for
+ a fairly comprehensive listing). Inside of each LC_MESSAGES directory
+ you should place two files, one with your translations in it, called
+ <plugin name>.po (in this case, "demo.po"), and one that is a compiled
+ version of the ".po" file, called <plugin name>.mo (in this case,
+ "demo.mo"). On most linux systems, there is a tool you can use to pull
+ out most of the strings that you need to have translated from your PHP
+ files into a sample .po file:
+
+ xgettext --keyword=_ -d <plugin name> -s -C *.php
+
+ --keyword option tells xgettext what your strings are enclosed in
+ -d is the domain of your plugin which should be the plugin's name
+ -s tells xgettext to sort the results and remove duplicate strings
+ -C means you are translating a file with C/C++ type syntax (ie. PHP)
+ *.php is all the files you want translations for
+
+ Note, however, that this will not always pick up all strings, so you
+ should double-check manually. Of course, it's easiest if you just keep
+ track of all your strings as you are coding your plugin. Your .po file
+ will now look something like:
+
+ # SOME DESCRIPTIVE TITLE.
+ # Copyright (C) YEAR Free Software Foundation, Inc.
+ # FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
+ #
+ #, fuzzy
+ msgid ""
+ msgstr ""
+ "Project-Id-Version: PACKAGE VERSION\n"
+ "POT-Creation-Date: 2003-06-18 11:22-0600\n"
+ "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
+ "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
+ "Language-Team: LANGUAGE <LL@li.org>\n"
+ "MIME-Version: 1.0\n"
+ "Content-Type: text/plain; charset=CHARSET\n"
+ "Content-Transfer-Encoding: ENCODING\n"
+
+ #: functions.php:45
+ msgid "Hello"
+ msgstr ""
+
+ #: functions.php:87
+ msgid "Favorite Color"
+ msgstr ""
+
+ You should change the header to look something more like:
+
+ # Copyright (c) 1999-2003 The Squirrelmail Development Team
+ # Roland Bauerschmidt <rb@debian.org>, 1999.
+ msgid ""
+ msgstr ""
+ "Project-Id-Version: $Id: squirrelmail.po,v 1.10 2003/06/04 15:01:59
+ philippe_mingo Exp $\n"
+ "POT-Creation-Date: 2003-01-21 19:21+0100\n"
+ "PO-Revision-Date: 2003-01-21 21:01+0100\n"
+ "Last-Translator: Juergen Edner <juergen.edner@epost.de>\n"
+ "Language-Team: German <squirrelmail-i18n@lists.squirrelmail.net>\n"
+ "MIME-Version: 1.0\n"
+ "Content-Type: text/plain; charset=ISO-8859-1\n"
+ "Content-Transfer-Encoding: 8bit\n"
+
+ The most important thing to change here is the charset on the next to
+ last line. You'll want to keep a master copy of the .po file and make
+ a copy for each language you have a translation for. You'll need to
+ translate each string in the .po file:
+
+ msgid "Hello"
+ msgstr "Guten Tag"
+
+ After you're done translating, you can create the .mo file very simply
+ by running the following command (available on most linux systems):
+
+ msgfmt -o <plugin name>.mo <plugin name>.po
+
+ In the case of the "demo" plugin:
+
+ msgfmt -o demo.mo demo.po
+
+ Please be sure that the .po and .mo files both are named exactly the
+ same as the domain you bound in step 2 above and everything else works
+ automatically. In SquirrelMail, go to Options -> Display Preferences
+ and change your Language setting to see the translations in action!
+
+
+
+Documenting the Code (Optional)
+-------------------------------
+
+If you wish, you can use phpdoc (Javadoc-style) comments, when documenting your
+code.
+
+If you follow the standards that are followed between Squirrelmail core &
+plugin developers, the resulted documentation can be included with the rest of
+the Squirrelmail code & API documentation. Specifically, in the page-level
+docblock, declare the package to be 'plugins', and the subpackage to be the
+name of your plugin. For instance:
+
+/**
+ * demo.php
+ *
+ * Copyright (c) 2003 My Name <my-email-address>
+ * Licensed under the GNU GPL. For full terms see the file COPYING.
+ *
+ * @package plugins
+ * @subpackage demo
+ */
+
+The rest is up to you. Try to follow some common sense and document what is
+really needed. Documenting the code properly can be a big help not only to
+yourself, but to those who will take a look at your code, fix the bugs and even
+improve it, in the true open-source spirit that Squirrelmail was built upon.
+
+For more information about phpdocumentor and how to write proper-tagged
+comments, you are directed at:
+
+http://phpdocu.sourceforge.net/
+
+
+
+PLUGIN STANDARDS AND REQUIREMENTS
+=================================
+
+The SquirrelMail project has some important goals, such as avoiding the
+use of JavaScript, avoiding non-standard HTML tags, keeping file sizes
+small and providing the fastest webmail client on the Internet. As such,
+we'd like it if plugin authors coded with the same goals in mind that the
+core developers do. Common sense is always a good tool to have in your
+programming repertoire, but below is an outline of some standards that we
+ask you as a plugin developer to meet. Depending upon how far you bend
+these rules, we may not want to post your plugin on the SquirrelMail
+website... and of course, no one really wants your efforts to go to waste
+and for the SquirrelMail community to miss out on a potentially useful
+plugin, so please try to follow these guidelines as closely as possible.
+
+
+Small setup.php
+---------------
+
+In order for SquirrelMail to remain fast and lean, we are now asking
+that all plugin authors remove all unnecessary functionality from setup.php
+and refactor it into another file. There are a few ways to accomplish
+this, none of which are difficult. At a minimum, you'll want to have the
+squirrelmail_plugin_init_<plugin name>() function in setup.php, and naturally,
+you'll need functions that are merely stubs for each hook that you are using.
+One (but not the only) way to do it is:
+
+ function squirrelmail_plugin_init_demo()
+ {
+ global $squirrelmail_plugin_hooks;
+ $squirrelmail_plugin_hooks['generic_header']['demo'] = 'plugin_demo_header';
+ }
+ function plugin_demo_header()
+ {
+ include_once(SM_PATH . 'plugins/demo/functions.php');
+ plugin_demo_header_do();
+ }
+
+
+Internationalization
+--------------------
+
+Q: What is more disappointing to users in France who would make good
+ use of your plugin than learning that it is written entirely in English?
+A: Learning that they cannot send you a French translation file for your
+ plugin.
+
+There are thousands of users out there whose native tongue is not English,
+and when you develop your plugin without going through the three simple steps
+needed to internationalize it, you are effectively writing them all off.
+PLEASE consider internationalizing your plugin!
+
+
+Developing with E_ALL
+---------------------
+
+When you are developing your plugin, you should always have error reporting
+turned all the way up. You can do this by changing two settings in your
+php.ini and restarting your web server:
+
+ display_errors = On
+ error_reporting = E_ALL
+
+This way, you'll be sure to see all Notices, Warnings and Errors that your
+code generates (it's OK, really, it happens to the best of us... except me!).
+Please make sure to fix them all before you release the plugin.
+
+
+Compatibility with register_globals=Off
+---------------------------------------
+
+Most sensible systems administrators now run their PHP systems with the
+setting "register_globals" as OFF. This is a prudent security setting,
+and as the SquirrelMail core code has long since been upgraded to work
+in such an environment, we are now requiring that all plugins do the same.
+Compatibility with this setting amounts to little more than explicitly
+gathering any and all variables you sent from a <form> tag as GET or POST
+values instead of just assuming that they will be placed in the global
+scope automatically. There is nothing more to do than this:
+
+ global $favorite_color;
+ sqgetGlobalVar('favorite_color', $favorite_color, SQ_FORM);
+
+
+Extra Blank Lines
+-----------------
+
+It may seem innocuous, but if you have any blank lines either before the
+first <?php tag or after the last ?> tag in any of your plugin files, you
+you will break SquirrelMail in ways that may seem entirely unrelated. For
+instance, this will often cause a line feed character to be included with
+email attachments when they are viewed or downloaded, rendering them useless!
+
+
+include_once
+------------
+
+When including files, please make sure to use the include_once() function
+and NOT include(), require(), or require_once(), since these all are much
+less efficient than include_once() and can have a cumulative effect on
+SquirrelMail performance.
+
+
+Version Reporting
+-----------------
+
+In order for systems administrators to keep better track of your plugin and
+get upgrades more efficiently, you are requested to make version information
+available to SquirrelMail in a format that it understands. There are two
+ways to do this. Presently, we are asking that you do both, since we are
+still in a transition period between the two. This is painless, so please
+be sure to include it:
+
+ 1. Create a file called "version" in the plugin directory. That file
+ should have only two lines: the first line should have the name of
+ the plugin as named on the SquirrelMail web site (this is often a
+ prettified version of the plugin directory name), the second line
+ must have the version and nothing more. So for our "demo" plugin,
+ whose name on the web site might be something like "Demo Favorite
+ Colors", the file plugins/demo/version should have these two lines:
+
+ Demo Favorite Colors
+ 1.0
+
+ 2. In setup.php, you should have a function called <plugin name>_version().
+ That function should return the version of your plugin. For the "demo"
+ plugin, that should look like this:
+
+ function demo_version()
+ {
+ return '1.0';
+ }
+
+
+Configuration Files
+-------------------
+
+It is common to need a configuration file that holds some variables that
+are set up at install time. For ease of installation and maintenance, you
+should place all behavioral settings in a config file, isolated from the
+rest of your plugin code. A typical file name to use is "config.php". If
+you are using such a file, you should NOT include a file called "config.php"
+in your plugin distribution, but instead a copy of that file called
+"config.php.sample". This helps systems administrators avoid overwriting
+the "config.php" files and losing all of their setup information when they
+upgrade your plugin.
+
+
+Session Variables
+-----------------
+
+In the past, there have been some rather serious issues with PHP sessions
+and SquirrelMail, and certain people have worked long and hard to ensure
+that these problems no longer occur in an extremely wide variety of OS/PHP/
+web server environments. Thus, if you need to place any values into the
+user's session, there are some built-in SquirrelMail functions that you are
+strongly encouraged to make use of. Using them also makes your job easier.
+
+ 1. To place a variable into the session:
+
+ global $favorite_color;
+ $favoriteColor = 'green';
+ sqsession_register($favorite_color, 'favorite_color');
+
+ Strictly speaking, globalizing the variable shouldn't be necessary,
+ but certain versions of PHP seem to behave more predictably if you do.
+
+ 2. To retrieve a variable from the session:
+
+ global $favorite_color;
+ sqgetGlobalVar('favorite_color', $favorite_color, SQ_SESSION);
+
+ 3. You can also check for the presence of a variable in the session:
+
+ if (sqsession_is_registered('favorite_color'))
+ // do something important
+
+ 4. To remove a variable from the session:
+
+ global $favorite_color;
+ sqsession_unregister('favorite_color');
+
+ Strictly speaking, globalizing the variable shouldn't be necessary,
+ but certain versions of PHP seem to behave more predictably if you do.
+
+
+Form Variables
+--------------
+
+You are also encouraged to use SquirrelMail's built-in facilities to
+retrieve variables from POST and GET submissions. This is also much
+easier on you and makes sure that all PHP installations are accounted
+for (such as those that don't make the $_POST array automatically
+global, etc.):
+
+ global $favorite_color;
+ sqgetGlobalVar('favorite_color', $favorite_color, SQ_FORM);
+
+
+Files In Plugin Directory
+-------------------------
+
+There are a few files that you should make sure to include when you build
+your final plugin distribution:
+
+ 1. A copy of the file index.php from the main plugins directory. When
+ working in your plugin directory, just copy it in like this:
+
+ $ cp ../index.php .
+
+ This will redirect anyone who tries to browse to your plugin directory
+ to somewhere more appropriate. If you create other directories under
+ your plugin directory, you may copy the file there as well to be extra
+ safe. If you are storing sensitive configuration files or other data
+ in such a directory, you could even include a .htaccess file with the
+ contents "Deny From All" that will disallow access to that directory
+ entirely (when the target system is running the Apache web server).
+ Keep in mind that not all web servers will honor an .htaccess file, so
+ don't depend on it for security. Make sure not to put such a file in
+ your main plugin directory!
+
+ 2. A file that describes your plugin and offers detailed instructions for
+ configuration or help with troubleshooting, etc. This file is usually
+ entitled "README". Some useful sections to include might be:
+
+ Plugin Name and Author
+ Current Version
+ Plugin Features
+ Detailed Plugin Description
+ How-to for Plugin Configuration
+ Change Log
+ Future Ideas/Enhancements/To Do List
+
+ 3. A file that explains how to install your plugin. This file is typically
+ called "INSTALL". If you do not require any special installation
+ actions, you can probably copy one from another plugin or use this as
+ a template:
+
+ Installing the Demo Plugin
+ ==========================
+
+ 1) Start with untaring the file into the plugins directory.
+ Here is a example for the 1.0 version of the Demo plugin.
+
+ $ cd plugins
+ $ tar -zxvf demo-1.0-1.4.0.tar.gz
+
+ 2) Change into the demo directory, copy config.php.sample
+ to config.php and edit config.php, making adjustments as
+ you deem necessary. For more detailed explanations about
+ each of these parameters, consult the README file.
+
+ $ cd demo
+ $ cp config.php.sample config.php
+ $ vi config.php
+
+
+ 3) Then go to your config directory and run conf.pl. Choose
+ option 8 and move the plugin from the "Available Plugins"
+ category to the "Installed Plugins" category. Save and exit.
+
+ $ cd ../../config/
+ $ ./conf.pl
+
+
+ Upgrading the Demo Plugin
+ =========================
+
+ 1) Start with untaring the file into the plugins directory.
+ Here is a example for the 3.1 version of the demo plugin.
+
+ $ cd plugins
+ $ tar -zxvf demo-3.1-1.4.0.tar.gz
+
+
+ 2) Change into the demo directory, check your config.php
+ file against the new version, to see if there are any new
+ settings that you must add to your config.php file.
+
+ $ diff -Nau config.php config.php.sample
+
+ Or simply replace your config.php file with the provided sample
+ and reconfigure the plugin from scratch (see step 2 under the
+ installation procedure above).
+
+
+COMPATIBILITY WITH OLDER VERSIONS OF SQUIRRELMAIL
+=================================================
+
+Whenever new versions of SquirrelMail are released, there is always a
+considerable lag time before it is widely adopted. During that transitional
+time, especially when the new SquirrelMail version contains any architectural
+and/or functional changes, plugin developers are put in a unique and very
+difficult position. That is, there will be people running both the old and
+new versions of SquirrelMail who want to use your plugin, and you will
+probably want to accomodate them both.
+
+The easiest way to keep both sides happy is to keep two different versions
+of your pluign up to date, one that runs under the older SquirrelMail, and
+one that requires the newest SquirrelMail. This is inconvenient, however,
+especially if you are continuing to develop the plugin. Depending on the
+changes the SquirrelMail has implemented in the new version, you may be able
+to include code that can auto-sense SquirrelMail version and make adjustments
+on the fly. There is a function available to you for determining the
+SquirrelMail version called check_sm_version() and it can be used as such:
+
+ check_sm_version(1, 4, 0)
+
+This will return TRUE if the SquirrelMail being used is at least 1.4.0, and
+FALSE otherwise.
+
+As this document is written, we are in a transition period between versions
+1.2.11 and 1.4.0. There is a plugin called "Compatibilty" that is intended
+for use by plugin authors so they can develop one version of their plugin
+and seamlessly support both 1.2.x and 1.4.x SquirrelMail installations. For
+more information about how to use the "Compatibility" plugin, download it and
+read its README file or see:
+
+ http://www.squirrelmail.org/wiki/wiki.php?PluginUpgrading
+
+
+REQUESTING NEW HOOKS
+====================
+
+It's impossible to foresee all of the places where hooks might be useful
+(it's also impossible to put in hooks everywhere!), so you might need to
+negotiate the insertion of a new hook to make your plugin work. In order
+to do so, you should post such a request to the squirrelmail-devel mailing
+list.
+
+
+HOW TO RELEASE YOUR PLUGIN
+==========================
+
+As long as you've consulted the list of plugin standards and done your
+best to follow them, there's little standing in the way of great fame as an
+official SquirrelMail plugin developer.
+
+ 1. Make a distribution file. There is a convenient Perl script in
+ the plugins directory that will help you do this:
+
+ make_archive.pl -v demo 1.0 1.4.0
+
+ -v is optional and indicates that the script should run in verbose mode
+ demo is the name of your plugin
+ 1.0 is the version of your plugin
+ 1.4.0 is the version of SquirrelMail that is required to run your plugin
+
+ You can also create the distribution file manually in most *nix
+ environments by running this command from the plugins directory (NOT
+ your plugin directory):
+
+ $ tar czvf demo-1.0-1.4.0.tar.gz demo
+
+ Where "demo" is the name of your plugin, "1.0" is the version of
+ your plugin, and "1.4.0" is the version of SquirrelMail required
+ to use your plugin.
+
+ 2. Consult the SquirrelMail web site for contact information for the
+ Plugins Team Leaders, to whom you should make your request. If they
+ do not respond, you should feel free to ask for help contacting them
+ on the squirrelmail-plugins mailing list.
+
+ http://www.squirrelmail.org/wiki/wiki.php?SquirrelMailLeadership
+
projects / squirrelmail.git / blobdiff