| 1 | $Id$ |
| 2 | |
| 3 | It is best if you check out the SquirrelMail development FAQ for more |
| 4 | information. This document may be obsoleted at some point in the future (or |
| 5 | maybe we'll write a script to get the wiki contents and dump them in here |
| 6 | automatically). |
| 7 | |
| 8 | FAQ -> http://www.squirrelmail.org/wiki/wiki.php?DeveloperFAQ |
| 9 | Plugin Hooks -> http://www.squirrelmail.org/wiki/wiki.php?DevelopingPlugins |
| 10 | |
| 11 | |
| 12 | A FEW NOTES ON THE PLUGIN ARCHITECTURE |
| 13 | ====================================== |
| 14 | |
| 15 | The plugin architecture of SquirrelMail is designed to make it possible to |
| 16 | add new features without having to patch SquirrelMail itself. Functionality |
| 17 | like password changing, displaying ads and calendars should be possible to |
| 18 | add as plugins. |
| 19 | |
| 20 | |
| 21 | The idea |
| 22 | -------- |
| 23 | |
| 24 | The idea is to be able to run random code at given places in the |
| 25 | SquirrelMail code. This random code should then be able to do whatever |
| 26 | needed to enhance the functionality of SquirrelMail. The places where |
| 27 | code can be executed are called "hooks". |
| 28 | |
| 29 | There are some limitations in what these hooks can do. It is difficult |
| 30 | to use them to change the layout and to change functionality that |
| 31 | already is in SquirrelMail. |
| 32 | |
| 33 | Some way for the plugins to interact with the help subsystem and |
| 34 | translations will be provided. |
| 35 | |
| 36 | |
| 37 | The implementation |
| 38 | ------------------ |
| 39 | |
| 40 | In the main SquirrelMail files the file functions/plugin.php. In |
| 41 | places where hooks are made available they are executed by calling the |
| 42 | function do_hook('hookname'). |
| 43 | |
| 44 | The do_hook traverses the array $squirrelmail_plugin_hooks['hookname'] |
| 45 | and executes all the functions that are named in that array. |
| 46 | |
| 47 | A plugin must reside in a subdirectory in the plugins/ directory. The |
| 48 | name of the subdirectory is considered the name of the plugin. |
| 49 | |
| 50 | To start using a plugin, its name must be added to the $plugins array |
| 51 | in config.php like this: |
| 52 | |
| 53 | $plugins[0] = 'plugin_name'; |
| 54 | |
| 55 | When a plugin is registered the file plugins/plugin_name/setup.php is |
| 56 | included and the function squirrelmail_plugin_init_plugin_name is |
| 57 | called with no parameters. |
| 58 | |
| 59 | |
| 60 | Writing plugins |
| 61 | --------------- |
| 62 | |
| 63 | A plugin must consist of at least a file called setup.php. All other |
| 64 | files the plugin consist of should also be in the plugin directory. |
| 65 | |
| 66 | The function squirrelmail_plugin_init_plugin_name is called to |
| 67 | initalize a plugin. This function could look something like this: |
| 68 | |
| 69 | function squirrelmail_plugin_init_demo () { |
| 70 | global $squirrelmail_plugin_hooks; |
| 71 | |
| 72 | $squirrelmail_plugin_hooks['generic_header']['demo'] = 'plugin_demo_header'; |
| 73 | $squirrelmail_plugin_hooks['menuline']['demo'] = 'plugin_demo_menuline'; |
| 74 | } |
| 75 | |
| 76 | Note that the SquirrelMail files assume that all other SquirrelMail |
| 77 | files are available as ../directory/file. This means that if some file |
| 78 | in the plugin directory is requested, it must do a chdir('..') before |
| 79 | including any of the standard SquirrelMail files. |
| 80 | |
| 81 | |
| 82 | Hook Data Passed |
| 83 | ---------------- |
| 84 | Hooks, when executed, are called with one parameter, an array of data |
| 85 | that is passed to the hook. The first element in the array is the name |
| 86 | of the hook that is being called. Any other elements in the array are |
| 87 | dependant on the type of hook that is being called. |
| 88 | |
| 89 | Some of the information in the array may be changed. By default, the |
| 90 | plugins should never change data unless it is documented otherwise. |
| 91 | |
| 92 | |
| 93 | List of hooks |
| 94 | ------------- |
| 95 | generic_header functions/page_header.php |
| 96 | menuline functions/page_header.php |
| 97 | compose_button_row src/compose.php |
| 98 | compose_bottom src/compose.php |
| 99 | compose_form src/compose.php |
| 100 | compose_send src/compose.php |
| 101 | left_main_before src/left_main.php |
| 102 | left_main_after src/left_main.php |
| 103 | * options_save src/options.php (see note on options) |
| 104 | * options_link_and_description src/options.php (see note on options) |
| 105 | * options_highlight_bottom src/options_highlight.php |
| 106 | * options_personal_bottom src/options_personal.php |
| 107 | * options_personal_inside src/options_personal.php |
| 108 | * options_personal_save src/options_personal.php |
| 109 | * options_display_bottom src/options_display.php |
| 110 | * options_display_inside src/options_display.php |
| 111 | * options_display_save src/options_display.php |
| 112 | * options_folders_bottom src/options_folders.php |
| 113 | * options_folders_inside src/options_folders.php |
| 114 | * options_folders_save src/options_folders.php |
| 115 | & options_identities_process src/options_identities.php |
| 116 | & options_identities_top src/options_identities.php |
| 117 | & options_identities_renumber src/options_identities.php (multiple places) |
| 118 | & options_identities_table src/options_identities.php |
| 119 | & options_identities_buttons src/options_identities.php |
| 120 | logout src/signout.php |
| 121 | logout_above_text src/signout.php |
| 122 | login_before src/webmail.php |
| 123 | login_verified src/webmail.php |
| 124 | loading_prefs src/load_prefs.php |
| 125 | mailbox_index_before functions/mailbox_display.php |
| 126 | mailbox_index_after functions/mailbox_display.php |
| 127 | mailbox_form_before functions/mailbox_display.php |
| 128 | subject_link functions/mailbox_display.php |
| 129 | motd src/right_main.php |
| 130 | right_main_after_header src/right_main.php |
| 131 | right_main_bottom src/right_main.php |
| 132 | login_top src/login.php |
| 133 | login_bottom src/login.php |
| 134 | html_top src/read_body.php |
| 135 | read_body_top src/read_body.php |
| 136 | read_body_bottom src/read_body.php |
| 137 | html_bottom src/read_body.php |
| 138 | read_body_header src/read_body.php |
| 139 | read_body_header_right src/read_body.php |
| 140 | search_before_form src/search.php |
| 141 | search_after_form src/search.php |
| 142 | search_bottom src/search.php |
| 143 | help_top src/help.php |
| 144 | help_bottom src/help.php |
| 145 | help_chapter src/help.php |
| 146 | addrbook_html_search_below src/addrbook_search_html.php |
| 147 | addressbook_bottom src/addressbook.php |
| 148 | ^ attachment $type0/$type1 functions/mime.php (see note on attachments) |
| 149 | |
| 150 | (*) Options |
| 151 | ----------- |
| 152 | There are two ways to do options for your plugin. First, you can incorporate it |
| 153 | into an existing section of the preferences (Display, Personal, or Folders). |
| 154 | The second way, you create your own section that they can choose from and it |
| 155 | displays its own range of options. |
| 156 | |
| 157 | |
| 158 | First: Integrating into existing options |
| 159 | ----------------------------------------- |
| 160 | There are two hooks you need to use for this one: |
| 161 | |
| 162 | 1. options_YOUCHOOSE_inside |
| 163 | This is the code that goes inside the table for the section you choose. Since |
| 164 | it is going inside an existing table, it must be in this form: |
| 165 | ------cut here------- |
| 166 | <tr> |
| 167 | <td> |
| 168 | OPTION_NAME |
| 169 | </td> |
| 170 | <td> |
| 171 | OPTION_INPUT |
| 172 | </td> |
| 173 | </tr> |
| 174 | ------cut here------- |
| 175 | |
| 176 | 2. options_YOUCHOOSE_save |
| 177 | This is the code that saves your preferences into the users' preference |
| 178 | file. For an example of how to do this, see src/options.php. |
| 179 | |
| 180 | |
| 181 | Second: Create your own section |
| 182 | ------------------------------- |
| 183 | It is possible to create your own options sections with plugins. There are |
| 184 | three hooks you will need to use. |
| 185 | |
| 186 | 1. options_link_and_description |
| 187 | This creates the link and has a description that is shown on the options |
| 188 | page. This should output HTML that looks like this. Make sure to read |
| 189 | the section on outputing your own pages. |
| 190 | |
| 191 | -----cut here----- |
| 192 | function my_plugin_name_my_function() { |
| 193 | global $color |
| 194 | ?> |
| 195 | <table width=50% cellpadding=3 cellspacing=0 border=0 align=center> |
| 196 | <tr> |
| 197 | <td bgcolor="<?php echo $color[9] ?>"> |
| 198 | <a href="../plugins/YOUR_PLUGIN/YOUR_OPTIONS.php">YOUR OPTIONS NAME</a> |
| 199 | </td> |
| 200 | </tr> |
| 201 | <tr> |
| 202 | <td bgcolor="<?php echo $color[0] ?>"> |
| 203 | YOUR DESCRIPTION |
| 204 | </td> |
| 205 | </tr> |
| 206 | </table> |
| 207 | <?php |
| 208 | } |
| 209 | -----cut here----- |
| 210 | |
| 211 | 2. options_save |
| 212 | Here is the code that you need to do to save your options in the |
| 213 | preference files or manipulate whatever data you are trying to change |
| 214 | through the options section. You can look at options.php for details |
| 215 | on how this is to be done. |
| 216 | |
| 217 | 3. loading_prefs (optional) |
| 218 | If you are wanting to save preferences to the preference files, then |
| 219 | you need to do this step as well. Otherwise if you are manipulating |
| 220 | other data, ignore this step. |
| 221 | |
| 222 | You should put the code in here that loads your preferences back |
| 223 | into usable variables. Examples of this can be found in the file |
| 224 | src/load_prefs.php |
| 225 | |
| 226 | |
| 227 | (&) Identity Hooks |
| 228 | ------------------ |
| 229 | Some hooks are passed special information in the array of arguments. See |
| 230 | the SpamCop plugin for how to use them. |
| 231 | |
| 232 | options_identities_process |
| 233 | [0] = Hook's name |
| 234 | [1] = Should I run the SaveUpdateFunction() (alterable) |
| 235 | |
| 236 | options_identities_renumber |
| 237 | [0] = Hook's name |
| 238 | [1] = Renumber it from ('default' or 1 through # idents - 1) |
| 239 | [2] = Renumber it to (same thing) |
| 240 | |
| 241 | options_identities_table |
| 242 | [0] = Hook's name |
| 243 | [1] = Color of table (use it like <tr<?PHP echo $Info[1]?>> in your |
| 244 | plugin) |
| 245 | [2] = Is this an empty section? |
| 246 | [3] = What is the 'post' value? |
| 247 | |
| 248 | options_identities_buttons |
| 249 | [0] = Hook's name |
| 250 | [1] = Is this an empty section (the one at the end of the list)? |
| 251 | [2] = What is the 'post' value? |
| 252 | |
| 253 | |
| 254 | (^) Attachment Hooks |
| 255 | -------------------- |
| 256 | When a message has attachments, this hook is called with the MIME types. For |
| 257 | instance, a .zip file hook is "attachment application/x-zip". The hook should |
| 258 | probably show a link to do a specific action, such as "Verify" or "View" for a |
| 259 | .zip file. |
| 260 | |
| 261 | This is a breakdown of the data passed in the array to the hook that is called: |
| 262 | |
| 263 | [0] = Hook's name ('attachment text/plain') |
| 264 | [1] = Array of links of actions (more below) (Alterable) |
| 265 | [2] = Used for returning to mail message (startMessage) |
| 266 | [3] = Used for finding message to display (id) |
| 267 | [4] = Mailbox name, urlencode()'d (urlMailbox) |
| 268 | [5] = Entity ID inside mail message (ent) |
| 269 | [6] = Default URL to go to when filename is clicked on (Alterable) |
| 270 | [7] = Filename that is displayed for the attachment |
| 271 | [8] = Sent if message was found from a search (where) |
| 272 | [9] = Sent if message was found from a search (what) |
| 273 | |
| 274 | To set up links for actions, you assign them like this: |
| 275 | |
| 276 | $Args[1]['your_plugin_name']['href'] = 'URL to link to'; |
| 277 | $Args[1]['your_plugin_name']['text'] = 'What to display'; |
| 278 | |
| 279 | It's also possible to specify a hook as "attachment type0/*", |
| 280 | for example "attachment text/*". This hook will be executed whenever there's |
| 281 | no more specific rule available for that type. |
| 282 | |
| 283 | |
| 284 | Outputting Your Own Pages |
| 285 | ------------------------- |
| 286 | |
| 287 | Often, when you want to provide your own customized options screen or create |
| 288 | another web page instead of just using standard hooks, you will be creating |
| 289 | your own .php files. An example of this is the attachment_common plugin's |
| 290 | image.php file. |
| 291 | |
| 292 | To make sure that security is maintained and standards are followed, the top |
| 293 | of your PHP script should look very similar to this: |
| 294 | |
| 295 | <?PHP |
| 296 | /* This is my php file. |
| 297 | * description goes here. |
| 298 | */ |
| 299 | |
| 300 | chdir('..'); |
| 301 | include('../src/validate.php'); |
| 302 | |
| 303 | The validate.php script will include internationalization support, |
| 304 | config.php variables, strings.php functions, and also authenticate that the |
| 305 | user is truly logged in. validate.php also calls stripslashes() on incoming |
| 306 | data (if gpc_magic_quotes() is on). You should never need to worry about |
| 307 | that stuff again. As a warning, this has only really been ironed out in |
| 308 | 1.1.1. If you create/modify a plugin to follow these rules, you must |
| 309 | mention that it requires SquirrelMail 1.1.1 or later. |
| 310 | |
| 311 | After that, if you need further functions, just use |
| 312 | |
| 313 | include('../functions/filename.php'); |
| 314 | |
| 315 | in your script. Since 1.0.5, it was no longer necessary (nor recommended) |
| 316 | to use the "if (! isset($filename_php))" syntax. |