place login form elements before login button. #1245070.
[squirrelmail.git] / doc / Development / plugin.txt
99098885 1$Id$
b6522eb5 3In addition to this document, please check out the SquirrelMail
4development FAQ for more information. Also, help writing plugins
9cd2ae7d 5is easily obtained by posting to the squirrelmail-plugins mailing
b2978b37 6list. (See details about mailing lists on the website)
99098885 7
8FAQ ->
b6522eb5 9Plugin Development ->
9cd2ae7d 10
99098885 11
b6522eb5 16The plugin architecture of SquirrelMail is designed to make it possible
17to add new features without having to patch SquirrelMail itself.
18Functionality like password changing, displaying ads and calendars should
9cd2ae7d 19be possible to add as plugins.
1aaef171 20
9cd2ae7d 22The Idea
1aaef171 23--------
25The idea is to be able to run random code at given places in the
26SquirrelMail code. This random code should then be able to do whatever
27needed to enhance the functionality of SquirrelMail. The places where
28code can be executed are called "hooks".
30There are some limitations in what these hooks can do. It is difficult
31to use them to change the layout and to change functionality that
32already is in SquirrelMail.
34Some way for the plugins to interact with the help subsystem and
35translations will be provided.
9cd2ae7d 38The Implementation
1aaef171 39------------------
9cd2ae7d 41The plugin jumping off point in the main SquirrelMail code is in the
42file functions/plugin.php. In places where hooks are made available,
b6522eb5 43they are executed by calling the function do_hook('hookname'). The
44do_hook function then traverses the array
45$squirrelmail_plugin_hooks['hookname'] and executes all the functions
46that are named in that array. Those functions are placed there when
47plugins register themselves with SquirrelMail as discussed below. A
48plugin may add its own internal functions to this array under any
9cd2ae7d 49hook name provided by the SquirrelMail developers.
1aaef171 50
51A plugin must reside in a subdirectory in the plugins/ directory. The
b6522eb5 52name of the subdirectory is considered to be the name of the plugin.
9cd2ae7d 53(The plugin will not function correctly if this is not the case.)
1aaef171 54
55To start using a plugin, its name must be added to the $plugins array
56in config.php like this:
9cd2ae7d 58 $plugins[0] = 'plugin_name';
1aaef171 59
9cd2ae7d 60When a plugin is registered, the file plugins/plugin_name/setup.php is
61included and the function squirrelmail_plugin_init_plugin_name() is
b6522eb5 62called with no parameters. That function is where the plugin may
9cd2ae7d 63register itself against any hooks it wishes to take advantage of.
1aaef171 64
b6522eb5 69All plugins must contain a file called setup.php and must include a
70function called squirrelmail_plugin_init_plugin_name() therein. Since
71including numerous plugins can slow SquirrelMail performance
72considerably, the setup.php file should contain little else. Any
73functions that are registered against plugin hooks should do little
9cd2ae7d 74more than call another function in a different file.
b6522eb5 76Any other files used by the plugin should also be placed in the
77plugin directory (or subdirectory thereof) and should contain the
9cd2ae7d 78bulk of the plugin logic.
1aaef171 79
9cd2ae7d 80The function squirrelmail_plugin_init_plugin_name() is called to
b6522eb5 81initalize a plugin. This function could look something like this (if
9cd2ae7d 82the plugin was named "demo" and resided in the directory plugins/demo/):
1aaef171 83
b6522eb5 84function squirrelmail_plugin_init_demo ()
9cd2ae7d 85{
86 global $squirrelmail_plugin_hooks;
1aaef171 87
9cd2ae7d 88 $squirrelmail_plugin_hooks['generic_header']['demo'] = 'plugin_demo_header';
89 $squirrelmail_plugin_hooks['menuline']['demo'] = 'plugin_demo_menuline';
92Please note that as of SquirrelMail 1.5.0, this function will no longer
93be called at run time and will instead be called only once at configure-
b6522eb5 94time. Thus, the inclusion of any dynamic code (anything except hook
9cd2ae7d 95registration) here is strongly discouraged.
1aaef171 96
9cd2ae7d 97In this example, the "demo" plugin should also have two other functions
98in its setup.php file called plugin_demo_header() and plugin_demo_menuline().
99The first of these might look something like this:
101function plugin_demo_header()
103 include_once(SM_PATH . 'plugins/demo/functions.php');
104 plugin_demo_header_do();
1aaef171 105}
9cd2ae7d 107The function called plugin_demo_header_do() would be in the file called
108functions.php in the demo plugin directory and would contain the plugin's
109core logic for the "generic_header" hook.
112Including Other Files
b6522eb5 115A plugin may need to reference functionality provided in other
9cd2ae7d 116files, and therefore need to include those files. Most of the
117core SquirrelMail functions are already available to your plugin
118unless it has any files that are requested directly by the client
b6522eb5 119browser (custom options page, etc.). In this case, you'll need
9cd2ae7d 120to make sure you include the files you need (see below).
122Note that as of SquirrelMail 1.4.0, all files are accessed using a
123constant called SM_PATH that always contains the relative path to
b6522eb5 124the main SquirrelMail directory. This constant is always available
125for you to use when including other files from the SquirrelMail core,
126your own plugin, or other plugins, should the need arise. If any of
127your plugin files are requested directly from the client browser,
9cd2ae7d 128you will need to define this constant before you do anything else:
130 define('SM_PATH', '../../');
132Files are included like this:
134 include_once(SM_PATH . 'include/validate.php');
136When including files, please make sure to use the include_once() function
b6522eb5 137and NOT include(), require(), or require_once(), since these all are much
138less efficient than include_once() and can have a cumulative effect on
9cd2ae7d 139SquirrelMail performance.
141The files that you may need to include in a plugin will vary greatly
142depending upon what the plugin is designed to do. For files that are
b6522eb5 143requested directly by the client browser, we strongly recommend that
144you include the file include/validate.php, since it will set up the
145SquirrelMail environment automatically. It will ensure the the user
146has been authenticated and is currently logged in, load all user
9cd2ae7d 147preferences, include internationalization support, call stripslashes()
b6522eb5 148on all incoming data (if magic_quotes_gpc is on), and initialize and
149include all other basic SquirrelMail resources and functions. You may
150see other plugins that directly include other SquirrelMail files, but
151that is no longer necessary and is a hold-over from older SquirrelMail
9cd2ae7d 152versions.
6b638171 153
e398ba12 154List of files, that are included by include/validate.php (If SquirrelMail
155version is not listed, files are included from v.1.3.2.):
156 1. class/mime.class.php
157 1.1. class/mime/Rfc822Header.class.php
158 1.2. class/mime/MessageHeader.class.php
159 1.3. class/mime/AddressStructure.class.php
160 1.4. class/mime/Message.class.php
161 1.5. class/mime/SMimeMessage.class.php
162 1.6. class/mime/Disposition.class.php
163 1.7. class/mime/Language.class.php
164 1.8. class/mime/ContentType.class.php
165 2. functions/global.php
166 3. functions/strings.php
167 4. config/config.php
168 4.1. config/config_local.php (from 1.4.0rc1)
169 5. functions/i18n.php
170 5.1. functions/global.php (from 1.4.0)
171 6. functions/auth.php
172 7. include/load_prefs.php
173 7.1. include/validate.php
174 7.2. functions/prefs.php
175 7.3. functions/plugin.php
176 7.3.1. functions/global.php (from 1.4.0 and 1.5.0)
177 7.3.2. functions/prefs.php (from 1.5.1)
178 7.4. functions/constants.php
179 7.5. do_hook('loading_prefs')
1f41d8b5 180 7.5.1. files loaded by plugins that use 'loading_prefs'
e398ba12 181 8. functions/page_header.php
182 8.1. functions/strings.php
183 8.2. functions/html.php
184 8.3. functions/imap_mailbox.php
185 8.3.1. functions/imap_utf7_local.php
186 8.4. functions/global.php
187 9. functions/prefs.php
188 9.1. functions/global.php
1f41d8b5 189 9.2. $prefs_backend (only in 1.4.3 and 1.5.0)
190 do_hook_function('prefs_backend') (since 1.4.4 and 1.5.1)
e398ba12 191 functions/db_prefs.php
192 functions/file_prefs.php
598294a7 193 9.2.1. functions/display_messages.php
de588ce6 194 (loaded only by file_prefs.php)
1f41d8b5 195 9.2.2. files loaded by plugin that uses 'prefs_backend'
6b638171 196
9cd2ae7d 197Hook Types: Parameters and Return Values
f4fd89e0 200Hooks, when executed, are called with differing parameters and may or may
201not take return values, all depending on the type of hook being called and
202the context in which it is being used. On the source side (where the hook
203call originates), all hooks have at least one parameter, which is the
204name of the hook. After that, things get complicated.
206 do_hook
207 -------
208 Most hook calls don't pass any data and don't ask for anything back.
209 These always use the do_hook call. A limited number of do_hook calls do
210 pass some extra parameters, in which case your plugin may modify the
211 given data if you do so by reference. It is not necessary to return
212 anything from your function in such a case; modifying the parameter
213 data by reference is what does the job (although the hook call itself
214 (in the source) must grab the return value for this to work). Note
215 that in this case, the parameter to your hook function will be an array,
216 the first element simply being the hook name, followed by any other
217 parameters that may have been included in the actual hook call in the
218 source. Modify parameters with care!
220 do_hook_function
221 ----------------
222 This hook type was intended to be the main hook type used when the
223 source needs to get something back from your plugin. It is somewhat
224 limited in that it will only use the value returned from the LAST
225 plugin registered against the hook. The source for this hook might
226 use the return value for internal purposes, or might expect you to
227 provide text or HTML to be sent to the client browser (you'll have to
228 look at its use in context to understand how you should return values
229 here). The parameters that your hook function gets will be anything
230 you see AFTER the hook name in the actual hook call in the source.
231 These cannot be changed in the same way that the do_hook parameters
232 can be.
234 concat_hook_function
235 --------------------
236 This is a newer hook type meant to address the shortcomings of
237 do_hook_function; specifically in that it uses the return values of
238 all plugins registered against the hook. In order to do so, the
239 return value is assumed to be a string, which is just piled on top
240 of whatever it got from the other plugins working on the same hook.
241 Again, you'll have to inspect the source code to see how such data
242 is put to use, but most of the time, it is used to create a string
243 of HTML to be inserted into the output page. The parameters that
244 your hook function will get are the same as for the do_hook_function;
245 they are anything AFTER the hook name in the actual hook call in the
246 source.
efea59ed 248 boolean_hook_function
249 ---------------------
f4fd89e0 250 The newest of the SquirrelMail hooks, this type is used to let all
251 plugins registered against the hook to "vote" for some action. What
252 that action is is entirely dependent on how the hook is used in the
253 source (look for yourself). Plugins make their "vote" by returning
254 TRUE or FALSE. This hook may be configured to "tally votes" in one
255 of three ways. This configuration is done with the third parameter
256 in the hook call in the source:
257 > 0 -- Any one or more TRUEs will override any FALSEs
258 < 0 -- Any one or more FALSEs will override any TRUEs
259 = 0 -- Majority wins. Ties are broken in this case with
260 the last parameter in the hook call in the source.
261 Your hook function will get the second paramter in the hook call in
262 the source as its parameter (this might be an array if multiple values
263 need to be passed).
a3a95e4a 264
f4fd89e0 265See below for further discussion of special hook types and the values
a3a95e4a 266
9cd2ae7d 268List of Hooks
6b638171 269-------------
ef3c69f0 270
9cd2ae7d 271This is a list of all hooks currently available in SquirrelMail, ordered
272by file. Note that this list is accurate as of June 17, 2003 (should be
273close to what is contained in release 1.4.1, plus or minus a hook or two),
274but may be out of date soon thereafter. You never know. ;-)
6b638171 275
9cd2ae7d 276 Hook Name Found In Called With(#)
277 --------- -------- --------------
df788686 278 abook_init functions/addressbook.php do_hook
279 abook_add_class functions/addressbook.php do_hook
9cd2ae7d 280 loading_constants functions/constants.php do_hook
54067ccd 281 logout_error functions/display_messages.php do_hook
282 error_box functions/display_messages.php concat_hook
9cd2ae7d 283 get_pref_override functions/file_prefs.php hook_func
284 get_pref functions/file_prefs.php hook_func
285 special_mailbox functions/imap_mailbox.php hook_func
f030c853 286% rename_or_delete_folder functions/imap_mailbox.php hook_func
9cd2ae7d 287 mailbox_index_before functions/mailbox_display.php do_hook
288 mailbox_form_before functions/mailbox_display.php do_hook
289 mailbox_index_after functions/mailbox_display.php do_hook
290 check_handleAsSent_result functions/mailbox_display.php do_hook
291 subject_link functions/mailbox_display.php concat_hook
c5aaf57f 292 mailbox_display_buttons functions/mailbox_display.php do_hook
7c788b1c 293 mailbox_display_button_action functions/mailbox_display.php hook_func
9cd2ae7d 294 message_body functions/mime.php do_hook
f030c853 295^ attachment $type0/$type1 functions/mime.php do_hook
9ad17edb 296 attachments_bottom functions/mime.php hook_func
c4115032 297 decode_body functions/mime.php hook_func
9cd2ae7d 298 generic_header functions/page_header.php do_hook
299 menuline functions/page_header.php do_hook
9d0239af 300 prefs_backend functions/prefs.php hook_func
9cd2ae7d 301 loading_prefs include/load_prefs.php do_hook
302 addrbook_html_search_below src/addrbook_search_html.php do_hook
303 addressbook_bottom src/addressbook.php do_hook
304 compose_form src/compose.php do_hook
305 compose_bottom src/compose.php do_hook
306 compose_button_row src/compose.php do_hook
307 compose_send src/compose.php do_hook
308 folders_bottom src/folders.php do_hook
309 help_top src/help.php do_hook
310 help_chapter src/help.php do_hook
311 help_bottom src/help.php do_hook
7022cc97 312 left_main_after_each_folder src/left_main.php concat_hook
9cd2ae7d 313 left_main_before src/left_main.php do_hook
314 left_main_after src/left_main.php do_hook
315 login_cookie src/login.php do_hook
316 login_top src/login.php do_hook
16436d92 317 login_form src/login.php concat_hook
318 (was do_hook before 1.5.1)
9cd2ae7d 319 login_bottom src/login.php do_hook
f030c853 320* optpage_set_loadinfo src/options.php do_hook
321* optpage_loadhook_personal src/options.php do_hook
322* optpage_loadhook_display src/options.php do_hook
323* optpage_loadhook_highlight src/options.php do_hook
324* optpage_loadhook_folder src/options.php do_hook
325* optpage_loadhook_order src/options.php do_hook
326* options_personal_save src/options.php do_hook
327* options_display_save src/options.php do_hook
328* options_folder_save src/options.php do_hook
329* options_save src/options.php do_hook
330* optpage_register_block src/options.php do_hook
331* options_link_and_description src/options.php do_hook
332* options_personal_inside src/options.php do_hook
333* options_display_inside src/options.php do_hook
334* options_highlight_inside src/options.php do_hook
335* options_folder_inside src/options.php do_hook
336* options_order_inside src/options.php do_hook
337* options_personal_bottom src/options.php do_hook
338* options_display_bottom src/options.php do_hook
339* options_highlight_bottom src/options.php do_hook
340* options_folder_bottom src/options.php do_hook
341* options_order_bottom src/options.php do_hook
342* options_highlight_bottom src/options_highlight.php do_hook
343& options_identities_process src/options_identities.php do_hook
344& options_identities_top src/options_identities.php do_hook
345&% options_identities_renumber src/options_identities.php do_hook
346& options_identities_table src/options_identities.php concat_hook
347& options_identities_buttons src/options_identities.php concat_hook
9cd2ae7d 348 message_body src/printer_friendly_bottom.php do_hook
349 read_body_header src/read_body.php do_hook
d44e63d5 350 read_body_menu_top src/read_body.php hook_func
9cd2ae7d 351 read_body_menu_bottom src/read_body.php do_hook
352 read_body_header_right src/read_body.php do_hook
9cd2ae7d 353 read_body_top src/read_body.php do_hook
354 read_body_bottom src/read_body.php do_hook
9cd2ae7d 355 login_before src/redirect.php do_hook
356 login_verified src/redirect.php do_hook
357 generic_header src/right_main.php do_hook
358 right_main_after_header src/right_main.php do_hook
359 right_main_bottom src/right_main.php do_hook
360 search_before_form src/search.php do_hook
361 search_after_form src/search.php do_hook
362 search_bottom src/search.php do_hook
363 logout src/signout.php do_hook
364 webmail_top src/webmail.php do_hook
d44e63d5 365 webmail_bottom src/webmail.php concat_hook
9cd2ae7d 366 logout_above_text src/signout.php concat_hook
f030c853 367O info_bottom plugins/info/options.php do_hook
b6522eb5 368
9cd2ae7d 369% = This hook is used in multiple places in the given file
370# = Called with hook type (see below)
371& = Special identity hooks (see below)
372^ = Special attachments hook (see below)
373* = Special options hooks (see below)
f030c853 374O = Optional hook provided by a particular plugin
6b638171 375
6b638171 376
9cd2ae7d 377(#) Called With
379Each hook is called using the hook type specified in the list above:
380 do_hook do_hook()
381 hook_func do_hook_function()
382 concat_hook concat_hook_function()
a3a95e4a 383
0f101579 385(&) Identity Hooks
9cd2ae7d 387This set of hooks is passed special information in the array of arguments:
0f101579 388
9cd2ae7d 390
b6522eb5 391 This hook is called at the top of the Identities page, which is
9cd2ae7d 392 most useful when the user has changed any identity settings - this
393 is where you'll want to save any custom information you are keeping
394 for each identity or catch any custom submit buttons that you may
395 have added to the identities page. The arguments to this hook are:
397 [0] = hook name (always "options_identities_process")
398 [1] = should I run the SaveUpdateFunction() (alterable)
400 Obviously, set the second array element to 1/true if you want to
401 trigger SaveUpdateFunction() after the hook is finished - by default,
402 it will not be called.
0f101579 403
9cd2ae7d 405
406 This hook is called when one of the identities is being renumbered,
b6522eb5 407 such as if the user had three identities and deletes the second -
9cd2ae7d 408 this hook would be called with an array that looks like this:
409 ('options_identities_renumber', 2, 1). The arguments to this hook
410 are:
412 [0] = hook name (always "options_identities_renumber")
413 [1] = being renumbered from ('default' or 1 through (# idents) - 1)
414 [2] = being renumbered to ('default' or 1 through (# idents) - 1)
b6522eb5 415
0f101579 416options_identities_table
9cd2ae7d 417
418 This hook allows you to insert additional rows into the table that
419 holds each identity. The arguments to this hook are:
23e3aacf 421 [0] = additional html attributes applied to table row.
422 use it like this in your plugin:
423 <tr "<?php echo $args[0]; ?>">
9cd2ae7d 424 [1] = is this an empty section (the one at the end of the list)?
425 [2] = what is the 'post' value? (ident # or empty string if default)
427 You need to return any HTML you would like to add to the table.
428 You could add a table row with code similar to this:
b6522eb5 430 function demo_identities_table(&$args)
9cd2ae7d 431 {
432 return '<tr bgcolor="' . $args[0] . '"><td>&nbsp;</td><td>'
433 . 'YOUR CODE HERE' . '</td></tr>' . "\n";
434 }
b6522eb5 435
23e3aacf 436 First hook argument was modified in 1.4.5/1.5.1. In SquirrelMail 1.4.1-1.4.4
437 and 1.5.0 argument contains only background color. You should use
438 <tr bgcolor="<?php echo $args[0]; ?>"> in these SquirrelMail versions.
0f101579 440options_identities_buttons
9cd2ae7d 441
442 This hook allows you to add a button (or other HTML) to the row of
443 buttons under each identity. The arguments to this hook are:
445 [0] = is this an empty section (the one at the end of the list)?
446 [1] = what is the 'post' value? (ident # or empty string if default)
b6522eb5 448 You need to return any HTML you would like to add here. You could add
9cd2ae7d 449 a button with code similar to this:
451 function demo_identities_button(&$args)
452 {
453 return '<input type="submit" name="demo_button_' . $args[1]
5f75494f 454 . '" value="Press Me" />';
9cd2ae7d 455 }
0f101579 456
a3a95e4a 458(^) Attachment Hooks
460When a message has attachments, this hook is called with the MIME types. For
461instance, a .zip file hook is "attachment application/x-zip". The hook should
462probably show a link to do a specific action, such as "Verify" or "View" for a
9cd2ae7d file. Thus, to register your plugin for .zip attachments, you'd do this
464in setup.php (assuming your plugin is called "demo"):
466 $squirrelmail_plugin_hooks['attachment application/x-zip']['demo']
467 = 'demo_handle_zip_attachment';
a3a95e4a 468
469This is a breakdown of the data passed in the array to the hook that is called:
471 [0] = Hook's name ('attachment text/plain')
9cd2ae7d 472 [1] = Array of links of actions (see below) (alterable)
a3a95e4a 473 [2] = Used for returning to mail message (startMessage)
474 [3] = Used for finding message to display (id)
475 [4] = Mailbox name, urlencode()'d (urlMailbox)
476 [5] = Entity ID inside mail message (ent)
9cd2ae7d 477 [6] = Default URL to go to when filename is clicked on (alterable)
ef30bf50 478 [7] = Filename that is displayed for the attachment
479 [8] = Sent if message was found from a search (where)
480 [9] = Sent if message was found from a search (what)
b6522eb5 481
a3a95e4a 482To set up links for actions, you assign them like this:
b6522eb5 483
9cd2ae7d 484 $Args[1]['<plugin_name>']['href'] = 'URL to link to';
21dab2dc 485 $Args[1]['<plugin_name>']['text'] = _("What to display");
d0201d63 486 $Args[1]['<plugin_name>']['extra'] = 'extra stuff, such as an <img ...> tag';
21dab2dc 487
488Note: _("What to display") is explained in the section about
b6522eb5 490
d0201d63 491You can leave the 'text' empty and put an image tag in 'extra' to show an
492image-only link for the attachment, or do the opposite (leave 'extra' empty)
493to display a text-only link.
ae2f65a9 495It's also possible to specify a hook as "attachment type0/*",
496for example "attachment text/*". This hook will be executed whenever there's
497no more specific rule available for that type.
9cd2ae7d 499Putting all this together, the demo_handle_zip_attachment() function should
500look like this (note the argument being passed):
57945c53 501
9cd2ae7d 502 function demo_handle_zip_attachment(&$Args)
503 {
504 include_once(SM_PATH . 'plugins/demo/functions.php');
505 demo_handle_zip_attachment_do($Args);
506 }
57945c53 507
9cd2ae7d 508And the demo_handle_zip_attachment_do() function in the
509plugins/demo/functions.php file would typically (but not necessarily)
510display a custom link:
512 function demo_handle_zip_attachment_do(&$Args)
513 {
514 $Args[1]['demo']['href'] = SM_PATH . 'plugins/demo/zip_handler.php?'
b6522eb5 515 . 'passed_id=' . $Args[3] . '&mailbox=' . $Args[4]
9cd2ae7d 516 . '&passed_ent_id=' . $Args[5];
21dab2dc 517 $Args[1]['demo']['text'] = _("Show zip contents");
9cd2ae7d 518 }
520The file plugins/demo/zip_handler.php can now do whatever it needs with the
521attachment (note that this will hand information about how to retrieve the
522source message from the IMAP server as GET varibles).
525(*) Options
527Before you start adding user preferences to your plugin, please take a moment
b6522eb5 528to think about it: in some cases, more options may not be a good thing.
529Having too many options can be confusing. Thinking from the user's
9cd2ae7d 530perspective, will the proposed options actually be used? Will users
531understand what these options are for?
533There are two ways to add options for your plugin. When you only have a few
534options that don't merit an entirely new preferences page, you can incorporate
b6522eb5 535them into an existing section of SquirrelMail preferences (Personal
536Information, Display Preferences, Message Highlighting, Folder Preferences or
537Index Order). Or, if you have an extensive number of settings or for some
9cd2ae7d 538reason need a separate page for the user to interact with, you can create your
539own preferences page.
542Integrating Your Options Into Existing SquirrelMail Preferences Pages
545There are two ways to accomplish the integration of your plugin's settings
b6522eb5 546into another preferences page. The first method is to add the HTML code
9cd2ae7d 547for your options directly to the preferences page of your choice. Although
548currently very popular, this method will soon be deprecated, so avoid it
b6522eb5 549if you can. That said, here is how it works. :) Look for any of the hooks
550named as "options_<pref page>_inside", where <pref page> is "display",
551"personal", etc. For this example, we'll use "options_display_inside" and,
9cd2ae7d 552as above, "demo" as our plugin name:
554 1. In setup.php in the squirrelmail_plugin_init_demo() function:
b6522eb5 556 $squirrelmail_plugin_hooks['options_display_inside']['demo']
9cd2ae7d 557 = 'demo_show_options';
559 Note that there are also hooks such as "options_display_bottom",
560 however, they place your options at the bottom of the preferences
561 page, which is usually not desirable (mostly because they also
562 come AFTER the HTML FORM tag is already closed). It is possible
563 to use these hooks if you want to create your own FORM with custom
564 submission logic.
566 2. Assuming the function demo_show_options() calls another function
567 elsewhere called demo_show_options_do(), that function should have
568 output similar to this (note that you will be inserting code into
569 a table that is already defined with two columns, so please be sure
570 to keep this framework in your plugin):
572 ------cut here-------
573 <tr>
574 <td>
576 </td>
577 <td>
579 </td>
b6522eb5 580 </tr>
9cd2ae7d 581 ------cut here-------
583 Of course, you can place any text where OPTION_NAME is and any input
b6522eb5 584 tags where OPTION_INPUT is.
9cd2ae7d 585
586 3. You will want to use the "options_<pref page>_save" hook (in this case,
587 "options_display_save") to save the user's settings after they have
b6522eb5 588 pressed the "Submit" button. Again, back in setup.php in the
9cd2ae7d 589 squirrelmail_plugin_init_demo() function:
57945c53 590
b6522eb5 591 $squirrelmail_plugin_hooks['options_display_save']['demo']
9cd2ae7d 592 = 'demo_save_options';
57945c53 593
9cd2ae7d 594 4. Assuming the function demo_save_options() calls another function
595 elsewhere called demo_save_options_do(), that function should put
596 the user's settings into permanent storage (see the preferences
597 section below for more information). This example assumes that
598 in the preferences page, the INPUT tag's NAME attribute was set
599 to "demo_option":
601 global $data_dir, $username;
602 sqgetGlobalVar('demo_option', $demo_option);
603 setPref($data_dir, $username, 'demo_option', $demo_option);
606The second way to add options to one of the SquirrelMail preferences page is
607to use one of the "optpage_loadhook_<pref page>" hooks. The sent_subfolders
60eeb409 608plugin has an excellent example of this method. Briefly, this way of adding
9cd2ae7d 609options consists of adding some plugin-specific information to a predefined
610data structure which SquirrelMail then uses to build the HTML input forms
611for you. This is the preferred method of building options lists going forward.
613 1. We'll use the "optpage_loadhook_display" hook to add a new group of
b6522eb5 614 options to the display preferences page. In setup.php in the
9cd2ae7d 615 squirrelmail_plugin_init_demo() function:
b6522eb5 617 $squirrelmail_plugin_hooks['optpage_loadhook_display']['demo']
9cd2ae7d 618 = 'demo_options';
620 2. Assuming the function demo_options() calls another function elsewhere
621 called demo_options_do(), that function needs to add a new key to two
622 arrays, $optpage_data['grps'] and $optpage_data['vals']. The value
623 associated with that key should simply be a section heading for your
624 plugin on the preferences page for the $optpage_data['grps'] array,
b6522eb5 625 and yet another array with all of your plugin's options for the
626 $optpage_data['vals'] array. The options are built as arrays (yes,
9cd2ae7d 627 that's four levels of nested arrays) that specify attributes that are
628 used by SquirrelMail to build your HTML input tags automatically.
629 This example includes just one input element, a SELECT (drop-down)
630 list:
632 global $optpage_data;
633 $optpage_data['grps']['DEMO_PLUGIN'] = 'Demo Options';
634 $optionValues = array();
635 $optionValues[] = array(
636 'name' => 'plugin_demo_favorite_color',
637 'caption' => 'Please Choose Your Favorite Color',
638 'type' => SMOPT_TYPE_STRLIST,
639 'refresh' => SMOPT_REFRESH_ALL,
640 'posvals' => array(0 => 'red',
641 1 => 'blue',
642 2 => 'green',
643 3 => 'orange'),
644 'save' => 'save_plugin_demo_favorite_color'
645 );
646 $optpage_data['vals']['DEMO_PLUGIN'] = $optionValues;
648 The array that you use to specify each plugin option has the following
649 possible attributes:
6976aad7 651 name The name of this setting, which is used not only for
652 the INPUT tag name, but also for the name of this
653 setting in the user's preferences
654 caption The text that prefaces this setting on the preferences
655 page
361d6e1b 656 trailing_text Text that follows a text input or select list input on
657 the preferences page (useful for indicating units,
658 meanings of special values, etc.)
6976aad7 659 type The type of INPUT element, which should be one of:
660 SMOPT_TYPE_STRING String/text input
661 SMOPT_TYPE_STRLIST Select list input
662 SMOPT_TYPE_TEXTAREA Text area input
663 SMOPT_TYPE_INTEGER Integer input
664 SMOPT_TYPE_FLOAT Floating point number input
665 SMOPT_TYPE_BOOLEAN Boolean (yes/no radio buttons)
60eeb409 666 input
6976aad7 667 SMOPT_TYPE_HIDDEN Hidden input (not actually
668 shown on preferences page)
669 SMOPT_TYPE_COMMENT Text is shown (specified by the
670 'comment' attribute), but no
671 user input is needed
672 SMOPT_TYPE_FLDRLIST Select list of IMAP folders
673 refresh Indicates if a link should be shown to refresh part or
674 all of the window (optional). Possible values are:
675 SMOPT_REFRESH_NONE No refresh link is shown
676 SMOPT_REFRESH_FOLDERLIST Link is shown to refresh
677 only the folder list
678 SMOPT_REFRESH_ALL Link is shown to refresh
679 the entire window
b6522eb5 680 initial_value The value that should initially be placed in this
6976aad7 681 INPUT element
682 posvals For select lists, this should be an associative array,
683 where each key is an actual input value and the
684 corresponding value is what is displayed to the user
685 for that list item in the drop-down list
686 value Specify the default/preselected value for this option
687 input
688 save You may indicate that special functionality needs to be
689 used instead of just saving this setting by giving the
b6522eb5 690 name of a function to call when this value would
6976aad7 691 otherwise just be saved in the user's preferences
692 size Specifies the size of certain input items (typically
693 textual inputs). Possible values are:
700 comment For SMOPT_TYPE_COMMENT type options, this is the text
701 displayed to the user
b6522eb5 702 script This is where you may add any additional javascript
6976aad7 703 or other code to the user input
704 post_script You may specify some script (usually Javascript) that
705 will be placed after (outside of) the INPUT tag.
ddb5b25c 706 htmlencoded disables html sanitizing. WARNING - don't use it, if user
707 input is possible in option or use own sanitizing functions.
708 Currently works only with SMOPT_TYPE_STRLIST.
9cd2ae7d 709
60eeb409 710 Note that you do not have to create a whole new section on the options
711 page if you merely want to add a simple input item or two to an options
712 section that already exists. For example, the Display Options page has
713 these groups:
715 0 - General Display Options
716 1 - Mailbox Display Options
717 2 - Message Display and Composition
719 To add our previous input drop-down to the Mailbox Display Options,
720 we would not have to create our own group; just add it to group
721 number one:
723 global $optpage_data;
724 $optpage_data['vals'][1][] = array(
725 'name' => 'plugin_demo_favorite_color',
726 'caption' => 'Please Choose Your Favorite Color',
727 'type' => SMOPT_TYPE_STRLIST,
728 'refresh' => SMOPT_REFRESH_ALL,
729 'posvals' => array(0 => 'red',
730 1 => 'blue',
731 2 => 'green',
732 3 => 'orange'),
733 'save' => 'save_plugin_demo_favorite_color'
734 );
9cd2ae7d 736 3. If you indicated a 'save' attribute for any of your options, you must
737 create that function (you'll only need to do this if you need to do
738 some special processing for one of your settings). The function gets
b6522eb5 739 one parameter, which is an object with mostly the same attributes you
9cd2ae7d 740 defined when you made the option above... the 'new_value' (and possibly
741 'value', which is the current value for this setting) is the most useful
742 attribute in this context:
744 function save_plugin_demo_favorite_color($option)
745 {
746 // if user chose orange, make note that they are really dumb
747 if ($option->new_value == 3)
748 {
749 // more code here as needed
750 }
752 // don't even save this setting if user chose green (old
753 // setting will remain)
754 if ($option->new_value == 2)
755 return;
757 // for all other colors, save as normal
758 save_option($option);
759 }
762Creating Your Own Preferences Page
765It is also possible to create your own preferences page for a plugin. This
b6522eb5 766is particularly useful when your plugin has numerous options or needs to
9cd2ae7d 767offer special interaction with the user (for things such as changing password,
768etc.). Here is an outline of how to do so (again, using the "demo" plugin
b6522eb5 771 1. Add a new listing to the main Options page. Older versions of
9cd2ae7d 772 SquirrelMail offered a hook called "options_link_and_description"
773 although its use is deprecated (and it is harder to use in that
774 it requires you to write your own HTML to add the option). Instead,
775 you should always use the "optpage_register_block" hook where you
776 create a simple array that lets SquirrelMail build the HTML
777 to add the plugin options entry automatically. In setup.php in the
778 squirrelmail_plugin_init_demo() function:
b6522eb5 779
9cd2ae7d 780 $squirrelmail_plugin_hooks['optpage_register_block']['demo']
781 = 'demo_options_block';
783 2. Assuming the function demo_options_block() calls another function
784 elsewhere called demo_options_block_do(), that function only needs
785 to create a simple array and add it to the $optpage_blocks array:
787 global $optpage_blocks;
788 $optpage_blocks[] = array(
789 'name' => 'Favorite Color Settings',
790 'url' => SM_PATH . 'plugins/demo/options.php',
791 'desc' => 'Change your favorite color & find new exciting colors',
792 'js' => FALSE
793 );
795 The array should have four elements:
796 name The title of the plugin's options as it will be displayed on
797 the Options page
798 url The URI that points to your plugin's custom preferences page
799 desc A description of what the preferences page offers the user,
800 displayed on the Options page below the title
801 js Indicates if this option page requires the client browser
802 to be Javascript-capable. Should be TRUE or FALSE.
b6522eb5 804 3. There are two different ways to create the actual preferences page
805 itself. One is to simply write all of your own HTML and other
806 interactive functionality, while the other is to define some data
9cd2ae7d 807 structures that allow SquirrelMail to build your user inputs and save
b6522eb5 808 your data automatically.
9cd2ae7d 809
b6522eb5 810 Building your own page is wide open, and for ideas, you should look at
9cd2ae7d 811 any of the plugins that currently have their own preferences pages. If
b6522eb5 812 you do this, make sure to read step number 4 below for information on
813 saving settings. In order to maintain security, consistant look and
9cd2ae7d 814 feel, internationalization support and overall integrity, there are just
815 a few things you should always do in this case: define the SM_PATH
816 constant, include the file include/validate.php (see the section about
817 including other files above) and make a call to place the standard page
818 heading at the top of your preferences page. The top of your PHP file
819 might look something like this:
821 define('SM_PATH', '../../');
822 include_once(SM_PATH . 'include/validate.php');
823 global $color;
824 displayPageHeader($color, 'None');
826 From here you are on your own, although you are encouraged to do things
827 such as use the $color array to keep your HTML correctly themed, etc.
b6522eb5 829 If you want SquirrelMail to build your preferences page for you,
830 creating input forms and automatically saving users' settings, then
9cd2ae7d 831 you should change the 'url' attribute in the options block you created
832 in step number 2 above to read as follows:
834 'url' => SM_PATH . 'src/options.php?optpage=plugin_demo',
b6522eb5 836 Now, you will need to use the "optpage_set_loadinfo" hook to tell
837 SquirrelMail about your new preferences page. In setup.php in the
9cd2ae7d 838 squirrelmail_plugin_init_demo() function:
b6522eb5 839
9cd2ae7d 840 $squirrelmail_plugin_hooks['optpage_set_loadinfo']['demo']
841 = 'demo_optpage_loadinfo';
843 Assuming the function demo_optpage_loadinfo() calls another function
b6522eb5 844 elsewhere called demo_optpage_loadinfo_do(), that function needs to
845 define values for four variables (make sure you test to see that it
9cd2ae7d 846 is your plugin that is being called by checking the GET variable you
847 added to the url just above):
b6522eb5 848
849 global $optpage, $optpage_name, $optpage_file,
9cd2ae7d 850 $optpage_loader, $optpage_loadhook;
851 if ($optpage == 'plugin_demo')
852 {
853 $optpage_name = "Favorite Color Preferences";
854 $optpage_file = SM_PATH . 'plugins/demo/options.php';
855 $optpage_loader = 'load_optpage_data_demo';
856 $optpage_loadhook = 'optpage_loadhook_demo';
857 }
859 Now you are ready to build all of your options. In the file you
860 indicated for the variable $optpage_file above, you'll need to create
861 a function named the same as the value you used for $optpage_loader
862 above. In this example, the file plugins/demo/options.php should
863 have at least this function in it:
865 function load_optpage_data_demo()
866 {
867 $optpage_data = array();
868 $optpage_data['grps']['DEMO_PLUGIN'] = 'Demo Options';
869 $optionValues = array();
870 $optionValues[] = array(
871 'name' => 'plugin_demo_favorite_color',
872 'caption' => 'Please Choose Your Favorite Color',
873 'type' => SMOPT_TYPE_STRLIST,
874 'refresh' => SMOPT_REFRESH_ALL,
875 'posvals' => array(0 => 'red',
876 1 => 'blue',
877 2 => 'green',
878 3 => 'orange'),
879 'save' => 'save_plugin_demo_favorite_color'
880 );
881 $optpage_data['vals']['DEMO_PLUGIN'] = $optionValues;
882 return $optpage_data;
883 }
885 For a detailed description of how you build these options, please read
886 step number 2 for the second method of adding options to an existing
887 preferences page above. Notice that the only difference here is in the
888 very first and last lines of this function where you are actually
889 creating and returning the options array instead of just adding onto it.
891 That's all there is to it - SquirrelMail will create a preferences page
892 titled as you indicated for $optpage_name above, and other plugins
893 can even add extra options to this new preferences page. To do so,
894 they should use the hook name you specified for $optpage_loadhook above
895 and use the second method for adding option settings to existing
896 preferences pages described above.
898 4. Saving your options settings: if you used the second method in step
899 number 3 above, your settings will be saved automatically (or you can
b6522eb5 900 define special functions to save special settings such as the
9cd2ae7d 901 save_plugin_demo_favorite_color() function in the example described
902 above) and there is probably no need to follow this step. If you
903 created your own preferences page from scratch, you'll need to follow
904 this step. First, you need to register your plugin against the
905 "options_save" hook. In setup.php in the squirrelmail_plugin_init_demo()
906 function:
b6522eb5 907
9cd2ae7d 908 $squirrelmail_plugin_hooks['options_save']['demo']
909 = 'demo_save_options';
911 Assuming the function demo_save_options() calls another function
912 elsewhere called demo_save_options_do(), that function needs to grab
913 all of your POST and/or GET settings values and save them in the user's
914 preferences (for more about preferences, see that section below). Since
b6522eb5 915 this is a generic hook called for all custom preferences pages, you
9cd2ae7d 916 should always set "optpage" as a POST or GET variable with a string that
917 uniquely identifies your plugin:
6fd95361 919 <input type="hidden" name="optpage" value="plugin_demo" />
9cd2ae7d 920
921 Now in your demo_save_options_do() function, do something like this:
923 global $username, $data_dir, $optpage, $favorite_color;
924 if ($optpage == 'plugin_demo')
925 {
926 sqgetGlobalVar('favorite_color', $favorite_color, SQ_FORM);
927 setPref($data_dir, $username, 'favorite_color', $favorite_color);
928 }
b6522eb5 929
930 Note that $favorite_color may not need to be globalized, although
9cd2ae7d 931 experience has shown that some versions of PHP don't behave as expected
932 unless you do so. Even when you use SquirrelMail's built-in preferences
b6522eb5 933 page generation functionality, you may still use this hook, although
934 there should be no need to do so. If you need to do some complex
9cd2ae7d 935 validation routines, note that it might be better to do so in the file
936 you specified as the "$optpage_file" (in our example, that was the
b6522eb5 937 plugins/demo/options.php file), since at this point, you can still
9cd2ae7d 938 redisplay your preferences page. You could put code similar to this
939 in the plugins/demp/options.php file (note that there is no function;
940 this code needs to be executed at include time):
942 global $optmode;
b6522eb5 943 if ($optmode == 'submit')
9cd2ae7d 944 {
945 // do something here such as validation, etc
946 if (you want to redisplay your preferences page)
947 $optmode = '';
948 }
954Saving and retrieving user preferences is very easy in SquirrelMail.
b6522eb5 955SquirrelMail supports preference storage in files or in a database
9cd2ae7d 956backend, however, the code you need to write to manipulate preferences
957is the same in both cases.
b6522eb5 959Setting preferences:
9cd2ae7d 960
961 Setting preferences is done for you if you use the built-in facilities
962 for automatic options construction and presentation (see above). If
963 you need to manually set preferences, however, all you need to do is:
965 global $data_dir, $username;
966 setPref($data_dir, $username, 'pref_name', $pref_value);
968 Where "pref_name" is the key under which the value will be stored
b6522eb5 969 and "pref_value" is a variable that should contain the actual
9cd2ae7d 970 preference value to be stored.
972Loading preferences:
974 There are two approaches to retrieving plugin (or any other) preferences.
975 You can grab individual preferences one at a time or you can add your
b6522eb5 976 plugin's preferences to the routine that loads up user preferences at
9cd2ae7d 977 the beginning of each page request. If you do the latter, making sure
978 to place your preference variables into the global scope, they will be
979 immediately available in all other plugin code. To retrieve a single
980 preference value at any time, do this:
982 global $data_dir, $username;
983 $pref_value = getPref($data_dir, $username, 'pref_name', 'default value');
985 Where "pref_name" is the preference you are retrieving, "default_value"
986 is what will be returned if the preference is not found for this user,
987 and, of course, "pref_value" is the variable that will get the actual
988 preference value.
990 To have all your preferences loaded at once when each page request is
991 made, you'll need to register a function against the "loading_prefs" hook.
992 For our "demo" plugin, in setup.php in the squirrelmail_plugin_init_demo()
993 function:
b6522eb5 994
9cd2ae7d 995 $squirrelmail_plugin_hooks['loading_prefs']['demo']
996 = 'demo_load_prefs';
998 Assuming the function demo_load_prefs() calls another function
999 elsewhere called demo_load_prefs_do(), that function just needs to
1000 pull out any all all preferences you'll be needing elsewhere:
1002 global $data_dir, $username, $pref_value;
1003 $pref_value = getPref($data_dir, $username, 'pref_name', 'default value');
1005 Remember to globalize each preference, or this code is useless.
1011Although this document may only be available in English, we sure hope that you
1012are thinking about making your plugin useful to the thousands of non-English
1013speaking SquirrelMail users out there! It is almost rude not to do so, and
1014it isn't much trouble, either. This document will only describe how you can
1015accomplish the internationalization of a plugin. For more general information
1016about PHP and SquirrelMail translation facilities, see:
1020The unofficial way to internationalize a plugin is to put all plugin output
1021into the proper format but to rely on the SquirrelMail translation facilities
1022for all the rest. If the plugin were really to get translated, you'd need
1023to make sure that all output strings for your plugin are either added to or
1024already exist in the main SquirrelMail locale files.
1026The better way to make sure your plugin is translated is to create your own
1027locale files and what is called a "gettext domain" (see the link above for
1028more information).
1030There are three basic steps to getting your plugins internationalized: put
b6522eb5 1031all output into the proper format, switch gettext domains and create locale
9cd2ae7d 1032files.
1034 1. Putting plugin output into the correct format is quite easy. The hard
1035 part is making sure you catch every last echo statement. You need to
1036 echo text like this:
1038 echo _("Hello");
1040 So, even in the HTML segments of your plugin files, you need to do this:
6fd95361 1042 <input type="submit" value="<?php echo _("Submit"); ?>" />
9cd2ae7d 1043
1044 You can put any text you want inside of the quotes (you MUST use double
b6522eb5 1045 quotes!), including HTML tags, etc. What you should think carefully
1046 about is that some languages may use different word ordering, so this
9cd2ae7d 1047 might be problematic:
1049 echo _("I want to eat a ") . $fruitName . _(" before noon");
1051 Because some languages (Japanese, for instance) would need to translate
b6522eb5 1052 such a sentence to "Before noon " . $fruitName . " I want to eat", but
1053 with the format above, they are stuck having to translate each piece
9cd2ae7d 1054 separately. You might want to reword your original sentence:
1056 echo _("This is what I want to eat before noon: ") . $fruitName;
45f574a7 1058 Note:
1059 Support for single quotes in gettext was added somewhere along gettext
1060 0.11.x (release dates 2002-01-31--08-06). This means that strings could
1061 be written as:
1063 echo _('Hello');
1065 However, gettext 0.10.40 is currently the oldest version available at the
1066 GNU site. It's still used in some Linux and BSD distributions/versions.
1067 Since it's still in common use and it doesn't support single quoted
1068 strings, double quoted strings are the preferred way when writing a
1069 plugin.
9cd2ae7d 1071 2. By default, the SquirrelMail gettext domain is always in use. That
1072 means that any text in the format described above will be translated
1073 using the locale files found in the main SquirrelMail locale directory.
1074 Unless your plugin produces no output or only output that is in fact
1075 translated under the default SquirrelMail domain, you need to create
1076 your own gettext domain. The PHP for doing so is very simple. At
1077 the top of any file that produces any output, place the following code
1078 (again, using "demo" as the plugin name):
1080 bindtextdomain('demo', SM_PATH . 'plugins/demo/locale');
1081 textdomain('demo');
1083 Now all output will be translated using your own custom locale files.
1084 Please be sure to switch back to the SquirrelMail domain at the end
1085 of the file, or many of the other SquirrelMail files may misbehave:
1087 bindtextdomain('squirrelmail', SM_PATH . 'locale');
1088 textdomain('squirrelmail');
1090 Note that if, in the middle of your plugin file, you use any
1091 SquirrelMail functions that send output to the browser, you'll need
1092 to temporarily switch back to the SquirrelMail domain:
1094 bindtextdomain('squirrelmail', SM_PATH . 'locale');
1095 textdomain('squirrelmail');
1096 displayPageHeader($color, 'None');
1097 bindtextdomain('demo', SM_PATH . 'plugins/demo/locale');
1098 textdomain('demo');
1100 Note that technically speaking, you only need to have one bindtextdomain
1101 call per file, you should always use it before every textdomain call,
1102 since PHP installations without gettext compiled into them will not
1103 function properly if you do not.
1105 3. Finally, you just need to create your own locale. You should create
1106 a directory structure like this in the plugin directory:
1108 demo
1109 |
1110 ------locale
1111 |
1112 ------de_DE
1113 | |
1114 | ------LC_MESSAGES
1115 |
1116 ------ja_JP
1117 |
1118 ------LC_MESSAGES
1120 Create a directories such as de_DE for each language (de_DE is German,
1121 ja_JP is Japanese, etc. - check the SquirrelMail locale directory for
1122 a fairly comprehensive listing). Inside of each LC_MESSAGES directory
1123 you should place two files, one with your translations in it, called
1124 <plugin name>.po (in this case, "demo.po"), and one that is a compiled
1125 version of the ".po" file, called <plugin name>.mo (in this case,
1126 ""). On most linux systems, there is a tool you can use to pull
1127 out most of the strings that you need to have translated from your PHP
1128 files into a sample .po file:
b6522eb5 1130 xgettext --keyword=_ -d <plugin name> -s -C *.php
9cd2ae7d 1131
1132 --keyword option tells xgettext what your strings are enclosed in
1133 -d is the domain of your plugin which should be the plugin's name
1134 -s tells xgettext to sort the results and remove duplicate strings
1135 -C means you are translating a file with C/C++ type syntax (ie. PHP)
1136 *.php is all the files you want translations for
b6522eb5 1138 Note, however, that this will not always pick up all strings, so you
9cd2ae7d 1139 should double-check manually. Of course, it's easiest if you just keep
1140 track of all your strings as you are coding your plugin. Your .po file
1141 will now look something like:
1144 # Copyright (C) YEAR Free Software Foundation, Inc.
1146 #
1147 #, fuzzy
1148 msgid ""
1149 msgstr ""
1150 "Project-Id-Version: PACKAGE VERSION\n"
1151 "POT-Creation-Date: 2003-06-18 11:22-0600\n"
1152 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
1153 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
1154 "Language-Team: LANGUAGE <>\n"
1155 "MIME-Version: 1.0\n"
1156 "Content-Type: text/plain; charset=CHARSET\n"
1157 "Content-Transfer-Encoding: ENCODING\n"
b6522eb5 1158
9cd2ae7d 1159 #: functions.php:45
1160 msgid "Hello"
1161 msgstr ""
b6522eb5 1162
9cd2ae7d 1163 #: functions.php:87
1164 msgid "Favorite Color"
1165 msgstr ""
b6522eb5 1166
9cd2ae7d 1167 You should change the header to look something more like:
9eb3fcb3 1169 # Copyright (c) 1999-2005 The SquirrelMail Project Team
9cd2ae7d 1170 # Roland Bauerschmidt <>, 1999.
df788686 1171 # $Id$
9cd2ae7d 1172 msgid ""
1173 msgstr ""
df788686 1174 "Project-Id-Version: plugin-name version\n"
9cd2ae7d 1175 "POT-Creation-Date: 2003-01-21 19:21+0100\n"
1176 "PO-Revision-Date: 2003-01-21 21:01+0100\n"
1177 "Last-Translator: Juergen Edner <>\n"
598294a7 1178 "Language-Team: German <>\n"
9cd2ae7d 1179 "MIME-Version: 1.0\n"
1180 "Content-Type: text/plain; charset=ISO-8859-1\n"
1181 "Content-Transfer-Encoding: 8bit\n"
1183 The most important thing to change here is the charset on the next to
1184 last line. You'll want to keep a master copy of the .po file and make
b6522eb5 1185 a copy for each language you have a translation for. You'll need to
9cd2ae7d 1186 translate each string in the .po file:
1188 msgid "Hello"
1189 msgstr "Guten Tag"
b6522eb5 1191 After you're done translating, you can create the .mo file very simply
9cd2ae7d 1192 by running the following command (available on most linux systems):
d2b351d7 1194 msgfmt -o <plugin name>.mo <plugin name>.po
9cd2ae7d 1195
1196 In the case of the "demo" plugin:
d2b351d7 1198 msgfmt -o demo.po
9cd2ae7d 1199
1200 Please be sure that the .po and .mo files both are named exactly the
1201 same as the domain you bound in step 2 above and everything else works
1202 automatically. In SquirrelMail, go to Options -> Display Preferences
1203 and change your Language setting to see the translations in action!
a7532db9 1206
1207Documenting the Code (Optional)
1210If you wish, you can use phpdoc (Javadoc-style) comments, when documenting your
598294a7 1213If you follow the standards that are followed between SquirrelMail core &
a7532db9 1214plugin developers, the resulted documentation can be included with the rest of
598294a7 1215the SquirrelMail code & API documentation. Specifically, in the page-level
a7532db9 1216docblock, declare the package to be 'plugins', and the subpackage to be the
1217name of your plugin. For instance:
b6522eb5 1218
a7532db9 1219/**
1220 * demo.php
1221 *
ba6338ee 1222 * Copyright (c) 2005 My Name <my-email-address>
a7532db9 1223 * Licensed under the GNU GPL. For full terms see the file COPYING.
1224 *
1225 * @package plugins
1226 * @subpackage demo
1227 */
1229The rest is up to you. Try to follow some common sense and document what is
1230really needed. Documenting the code properly can be a big help not only to
1231yourself, but to those who will take a look at your code, fix the bugs and even
598294a7 1232improve it, in the true open-source spirit that SquirrelMail was built upon.
a7532db9 1233
1234For more information about phpdocumentor and how to write proper-tagged
1235comments, you are directed at:
1244The SquirrelMail project has some important goals, such as avoiding the
1245use of JavaScript, avoiding non-standard HTML tags, keeping file sizes
1246small and providing the fastest webmail client on the Internet. As such,
1247we'd like it if plugin authors coded with the same goals in mind that the
1248core developers do. Common sense is always a good tool to have in your
b6522eb5 1249programming repertoire, but below is an outline of some standards that we
1250ask you as a plugin developer to meet. Depending upon how far you bend
1251these rules, we may not want to post your plugin on the SquirrelMail
9cd2ae7d 1252website... and of course, no one really wants your efforts to go to waste
1253and for the SquirrelMail community to miss out on a potentially useful
1254plugin, so please try to follow these guidelines as closely as possible.
1257Small setup.php
1260In order for SquirrelMail to remain fast and lean, we are now asking
1261that all plugin authors remove all unnecessary functionality from setup.php
d2b351d7 1262and refactor it into another file. There are a few ways to accomplish
9cd2ae7d 1263this, none of which are difficult. At a minimum, you'll want to have the
1264squirrelmail_plugin_init_<plugin name>() function in setup.php, and naturally,
1265you'll need functions that are merely stubs for each hook that you are using.
1266One (but not the only) way to do it is:
b6522eb5 1268 function squirrelmail_plugin_init_demo()
9cd2ae7d 1269 {
1270 global $squirrelmail_plugin_hooks;
1271 $squirrelmail_plugin_hooks['generic_header']['demo'] = 'plugin_demo_header';
1272 }
1273 function plugin_demo_header()
1274 {
1275 include_once(SM_PATH . 'plugins/demo/functions.php');
1276 plugin_demo_header_do();
1277 }
b6522eb5 1283Q: What is more disappointing to users in France who would make good
9cd2ae7d 1284 use of your plugin than learning that it is written entirely in English?
1285A: Learning that they cannot send you a French translation file for your
1286 plugin.
1288There are thousands of users out there whose native tongue is not English,
1289and when you develop your plugin without going through the three simple steps
b6522eb5 1290needed to internationalize it, you are effectively writing them all off.
9cd2ae7d 1291PLEASE consider internationalizing your plugin!
1294Developing with E_ALL
1297When you are developing your plugin, you should always have error reporting
1298turned all the way up. You can do this by changing two settings in your
1299php.ini and restarting your web server:
799c2046 1301 display_errors = On
9cd2ae7d 1302 error_reporting = E_ALL
1304This way, you'll be sure to see all Notices, Warnings and Errors that your
1305code generates (it's OK, really, it happens to the best of us... except me!).
1306Please make sure to fix them all before you release the plugin.
1b6b1526 1309Compatibility with register_globals=Off
1312Most sensible systems administrators now run their PHP systems with the
1313setting "register_globals" as OFF. This is a prudent security setting,
1314and as the SquirrelMail core code has long since been upgraded to work
1315in such an environment, we are now requiring that all plugins do the same.
1316Compatibility with this setting amounts to little more than explicitly
1317gathering any and all variables you sent from a <form> tag as GET or POST
1318values instead of just assuming that they will be placed in the global
1319scope automatically. There is nothing more to do than this:
1321 global $favorite_color;
1322 sqgetGlobalVar('favorite_color', $favorite_color, SQ_FORM);
68549369 1325Security considerations
ecc368a8 1328All plugin authors should consider the security implications of their
1329plugin. Of course, if you call external programs you have to use great
1330care, but the following issues are important to nearly every plugin.
68549369 1331
1332- Escape any untrusted data before you output it. This is to prevent
ecc368a8 1333cross site scripting attacks. It means that you have to htmlspecialchars()
68549369 1334every variable that comes in through the URL, a mail message or other
1335external factors, before outputting it.
1337- Make sure that your plugin doesn't perform its function when it's not
1338enabled. If you just call hooks, your hooks won't be called when the
1339plugin is disabled, but if you also supply extra .php files, you should
1340check if they perform any function if accessed directly. If they do, you
ecc368a8 1341should check at the start of that file whether the plugin is enabled in the
68549369 1342config, and if not, exit the script. Example:
1343 global $plugins;
1344 if ( !in_array('mypluginname', $plugins) ) {
1345 die("Plugin not enabled in SquirrelMail configuration.");
1346 }
1348If you have any questions about this or are unsure, please contact the
1349mailinglist or IRC channel, because security is very important for a
1350widely used application like SquirrelMail!
9cd2ae7d 1353Extra Blank Lines
1356It may seem innocuous, but if you have any blank lines either before the
1357first <?php tag or after the last ?> tag in any of your plugin files, you
1358you will break SquirrelMail in ways that may seem entirely unrelated. For
1359instance, this will often cause a line feed character to be included with
1360email attachments when they are viewed or downloaded, rendering them useless!
1366When including files, please make sure to use the include_once() function
b6522eb5 1367and NOT include(), require(), or require_once(), since these all are much
1368less efficient than include_once() and can have a cumulative effect on
9cd2ae7d 1369SquirrelMail performance.
1372Version Reporting
1375In order for systems administrators to keep better track of your plugin and
1376get upgrades more efficiently, you are requested to make version information
b6522eb5 1377available to SquirrelMail in a format that it understands. There are two
1378ways to do this. Presently, we are asking that you do both, since we are
1379still in a transition period between the two. This is painless, so please
9cd2ae7d 1380be sure to include it:
1382 1. Create a file called "version" in the plugin directory. That file
1383 should have only two lines: the first line should have the name of
1384 the plugin as named on the SquirrelMail web site (this is often a
b6522eb5 1385 prettified version of the plugin directory name), the second line
9cd2ae7d 1386 must have the version and nothing more. So for our "demo" plugin,
b6522eb5 1387 whose name on the web site might be something like "Demo Favorite
9cd2ae7d 1388 Colors", the file plugins/demo/version should have these two lines:
1390 Demo Favorite Colors
1391 1.0
1393 2. In setup.php, you should have a function called <plugin name>_version().
1394 That function should return the version of your plugin. For the "demo"
1395 plugin, that should look like this:
1397 function demo_version()
1398 {
1399 return '1.0';
1400 }
1403Configuration Files
1406It is common to need a configuration file that holds some variables that
1407are set up at install time. For ease of installation and maintenance, you
1408should place all behavioral settings in a config file, isolated from the
1409rest of your plugin code. A typical file name to use is "config.php". If
1410you are using such a file, you should NOT include a file called "config.php"
b6522eb5 1411in your plugin distribution, but instead a copy of that file called
9cd2ae7d 1412"config.php.sample". This helps systems administrators avoid overwriting
1413the "config.php" files and losing all of their setup information when they
1414upgrade your plugin.
1417Session Variables
1420In the past, there have been some rather serious issues with PHP sessions
1421and SquirrelMail, and certain people have worked long and hard to ensure
1422that these problems no longer occur in an extremely wide variety of OS/PHP/
b6522eb5 1423web server environments. Thus, if you need to place any values into the
1424user's session, there are some built-in SquirrelMail functions that you are
9cd2ae7d 1425strongly encouraged to make use of. Using them also makes your job easier.
1427 1. To place a variable into the session:
b6522eb5 1429 global $favorite_color;
9cd2ae7d 1430 $favoriteColor = 'green';
1431 sqsession_register($favorite_color, 'favorite_color');
1433 Strictly speaking, globalizing the variable shouldn't be necessary,
1434 but certain versions of PHP seem to behave more predictably if you do.
1436 2. To retrieve a variable from the session:
1438 global $favorite_color;
1439 sqgetGlobalVar('favorite_color', $favorite_color, SQ_SESSION);
1441 3. You can also check for the presence of a variable in the session:
1443 if (sqsession_is_registered('favorite_color'))
1444 // do something important
1446 4. To remove a variable from the session:
ea26c996 1448 global $favorite_color;
9cd2ae7d 1449 sqsession_unregister('favorite_color');
ea26c996 1451 Strictly speaking, globalizing the variable shouldn't be necessary,
1452 but certain versions of PHP seem to behave more predictably if you do.
9cd2ae7d 1454
1455Form Variables
b6522eb5 1458You are also encouraged to use SquirrelMail's built-in facilities to
9cd2ae7d 1459retrieve variables from POST and GET submissions. This is also much
1460easier on you and makes sure that all PHP installations are accounted
b6522eb5 1461for (such as those that don't make the $_POST array automatically
9cd2ae7d 1462global, etc.):
1464 global $favorite_color;
1465 sqgetGlobalVar('favorite_color', $favorite_color, SQ_FORM);
1468Files In Plugin Directory
1471There are a few files that you should make sure to include when you build
1472your final plugin distribution:
b6522eb5 1474 1. A copy of the file index.php from the main plugins directory. When
9cd2ae7d 1475 working in your plugin directory, just copy it in like this:
1477 $ cp ../index.php .
1479 This will redirect anyone who tries to browse to your plugin directory
1480 to somewhere more appropriate. If you create other directories under
1481 your plugin directory, you may copy the file there as well to be extra
1482 safe. If you are storing sensitive configuration files or other data
1483 in such a directory, you could even include a .htaccess file with the
b6522eb5 1484 contents "Deny From All" that will disallow access to that directory
9cd2ae7d 1485 entirely (when the target system is running the Apache web server).
1486 Keep in mind that not all web servers will honor an .htaccess file, so
1487 don't depend on it for security. Make sure not to put such a file in
1488 your main plugin directory!
b6522eb5 1490 2. A file that describes your plugin and offers detailed instructions for
1491 configuration or help with troubleshooting, etc. This file is usually
9cd2ae7d 1492 entitled "README". Some useful sections to include might be:
1494 Plugin Name and Author
1495 Current Version
1496 Plugin Features
1497 Detailed Plugin Description
1498 How-to for Plugin Configuration
1499 Change Log
1500 Future Ideas/Enhancements/To Do List
1502 3. A file that explains how to install your plugin. This file is typically
b6522eb5 1503 called "INSTALL". If you do not require any special installation
9cd2ae7d 1504 actions, you can probably copy one from another plugin or use this as
1505 a template:
1507 Installing the Demo Plugin
1508 ==========================
1510 1) Start with untaring the file into the plugins directory.
1511 Here is a example for the 1.0 version of the Demo plugin.
1513 $ cd plugins
1514 $ tar -zxvf demo-1.0-1.4.0.tar.gz
1516 2) Change into the demo directory, copy config.php.sample
1517 to config.php and edit config.php, making adjustments as
1518 you deem necessary. For more detailed explanations about
1519 each of these parameters, consult the README file.
b6522eb5 1520
9cd2ae7d 1521 $ cd demo
1522 $ cp config.php.sample config.php
1523 $ vi config.php
b6522eb5 1524
9cd2ae7d 1526 3) Then go to your config directory and run Choose
1527 option 8 and move the plugin from the "Available Plugins"
1528 category to the "Installed Plugins" category. Save and exit.
b6522eb5 1529
9cd2ae7d 1530 $ cd ../../config/
1531 $ ./
b6522eb5 1532
9cd2ae7d 1533
1534 Upgrading the Demo Plugin
1535 =========================
1537 1) Start with untaring the file into the plugins directory.
1538 Here is a example for the 3.1 version of the demo plugin.
1540 $ cd plugins
1541 $ tar -zxvf demo-3.1-1.4.0.tar.gz
1544 2) Change into the demo directory, check your config.php
1545 file against the new version, to see if there are any new
1546 settings that you must add to your config.php file.
1548 $ diff -Nau config.php config.php.sample
b6522eb5 1549
9cd2ae7d 1550 Or simply replace your config.php file with the provided sample
1551 and reconfigure the plugin from scratch (see step 2 under the
1552 installation procedure above).
1558Whenever new versions of SquirrelMail are released, there is always a
1559considerable lag time before it is widely adopted. During that transitional
1560time, especially when the new SquirrelMail version contains any architectural
1561and/or functional changes, plugin developers are put in a unique and very
1562difficult position. That is, there will be people running both the old and
b6522eb5 1563new versions of SquirrelMail who want to use your plugin, and you will
9cd2ae7d 1564probably want to accomodate them both.
1566The easiest way to keep both sides happy is to keep two different versions
1567of your pluign up to date, one that runs under the older SquirrelMail, and
1568one that requires the newest SquirrelMail. This is inconvenient, however,
1569especially if you are continuing to develop the plugin. Depending on the
1570changes the SquirrelMail has implemented in the new version, you may be able
1571to include code that can auto-sense SquirrelMail version and make adjustments
b6522eb5 1572on the fly. There is a function available to you for determining the
9cd2ae7d 1573SquirrelMail version called check_sm_version() and it can be used as such:
1575 check_sm_version(1, 4, 0)
1577This will return TRUE if the SquirrelMail being used is at least 1.4.0, and
1578FALSE otherwise.
1580As this document is written, we are in a transition period between versions
15811.2.11 and 1.4.0. There is a plugin called "Compatibilty" that is intended
1582for use by plugin authors so they can develop one version of their plugin
1583and seamlessly support both 1.2.x and 1.4.x SquirrelMail installations. For
1584more information about how to use the "Compatibility" plugin, download it and
1585read its README file or see:
1593It's impossible to foresee all of the places where hooks might be useful
1594(it's also impossible to put in hooks everywhere!), so you might need to
1595negotiate the insertion of a new hook to make your plugin work. In order
1596to do so, you should post such a request to the squirrelmail-devel mailing
1603As long as you've consulted the list of plugin standards and done your
1604best to follow them, there's little standing in the way of great fame as an
1605official SquirrelMail plugin developer.
1607 1. Make a distribution file. There is a convenient Perl script in
1608 the plugins directory that will help you do this:
1610 -v demo 1.0 1.4.0
1612 -v is optional and indicates that the script should run in verbose mode
1613 demo is the name of your plugin
1614 1.0 is the version of your plugin
1615 1.4.0 is the version of SquirrelMail that is required to run your plugin
b6522eb5 1617 You can also create the distribution file manually in most *nix
1618 environments by running this command from the plugins directory (NOT
9cd2ae7d 1619 your plugin directory):
1621 $ tar czvf demo-1.0-1.4.0.tar.gz demo
1623 Where "demo" is the name of your plugin, "1.0" is the version of
1624 your plugin, and "1.4.0" is the version of SquirrelMail required
1625 to use your plugin.
1627 2. Consult the SquirrelMail web site for contact information for the
b6522eb5 1628 Plugins Team Leaders, to whom you should make your request. If they
1629 do not respond, you should feel free to ask for help contacting them
9cd2ae7d 1630 on the squirrelmail-plugins mailing list.