How to write a module

You want to create a new module for Centreon 2 or to adapt an existing one? You’re at the right place!

You should know Centreon contains a page dedicated to the installation and the uninstallation of modules (Administration > Modules). To make the module appears on this page, its directory must be placed inside Cetreon’s modules/ directory. Example:

/usr/local/centreon/www/modules/module-Dummy

An empty module template can be found inside Centreon’s repository.

Basis

The essential elements your module’s directory must contain are presented below (* = required):

[conf.php]*:

// Short module's name. Must be equal to your module's directory name
$module_conf['dummy']['name'] = "dummy";
// Full module's name
$module_conf['dummy']['rname'] = "Dummy Module";
// Module's version
$module_conf['dummy']['mod_release'] = "2.0";
// Additional information
$module_conf['dummy']['infos'] = "First of all";
// Allow your module to be uninstalled
$module_conf['dummy']['is_removeable'] = "1";
// Module author's name
$module_conf['dummy']['author'] = "Centreon Team";
// 1: the module executes an SQL file for installation and/or uninstallation
// 0: the module doesn't execute any SQL file
$module_conf['dummy']['sql_files'] = "1";
// 1: the module executes a PHP file for installation and/or uninstallation
// 0: the module doesn't execute any SQL file
$module_conf['dummy']['php_files'] = "1";

[infos > infos.txt]

This file can contain various information about your module.

[php > install.php]

This PHP file is executed at module installation if it is configured inside the conf.php file.

[php > uninstall.php]

This PHP file is executed at module uninstallation if it is configured inside the conf.php file.

[sql > install.sql]

This SQL file is executed during the module installation if it is configured inside the conf.php file. If you want your module to be available from Centreon menus, you must insert new entries into the topology table of the centreon database. An example is available inside the Dummy module.

[sql > uninstall.sql]

This SQL file is executed during the module uninstallation if it is configured inside the conf.php file. It can also remove your module from Centreon menus.

[generate_files > *.php]

The PHP files contained inside the generate_files directory will be executed during the monitoring engine configuration files generation (inside Configuration > Monitoring Engines). Those files must generate configuration files.

[UPGRADE > dummy-x.x > sql > upgrade.sql]

Centreon provides an upgrade system for modules. To use it, just add a directory under UPGRADE named using the following pattern: <module name>-<version>. When clicking on the upgrade button, Centreon will search for scripts to execute, following the logical order of versions.

For example, if the version 1.0 of the dummy module is installed and the following directories exist:

$ ls UPGRADE
dummy-1.1 dummy-1.2

Centreon will execute the scripts in the following order : 1.1, 1.2. A configuration file in each upgrade directory is present in order to allow (or not) the execution.

You’re free to organize the remaining files (your module’s content) as you like.

Advanced

That’s great, you know how to install a module! As an empty module is not really usefull, put your imagination at work. Knowing that you can do almost everything, it should not be too complicated :-).

Connecting to the database

You can use the centreon, centstorage and ndo databases by calling the following file: centreon/www/class/centreonDB.class.php.

For example, execute requests like this:

<?
$pearDB = new CentreonDB();
$pearDB->query("SELECT * FROM host");
?>

Existing functions

You can access most of the functions already developed within Centreon using include() statements. They’re generally stored in centreon/www/class/.

Before developing your own function, check the existing code, it could spare your time!