Plugins - geavanceerd

Overzicht

Sinds versie 2.05 ondersteunt LimeSurvey plugins. Enkele plugins worden door het LimeSurvey-team feitelijk toegevoegd aan LimeSurvey. Andere plugins worden door anderen ondersteund. Je kunt ons vragen om hier een door jou gemaakte plugin te vermelden!

Met een plugin kun je de functionaliteit uitbreiden van LimeSurvey en toch gebruikt blijven maken van onze normale updates.

This documentation is meant for developers that are extending LimeSurvey for their own use or for their clients; end users will not be helped by this documentation.

Plugins must implement the iPlugin interface. We recommend extending your plugin class from the PluginBase class.

Plugins are developed around an event mechanism.

Plugin-instellingen

By extending you benefit from common functionality required by plugins that we already have implemented for you. One of these function is the implementation of the getPluginSettings function. This function must return an array describing the configuration options for the user.

The example plugin exposes just 1 configurable setting, the message it'll show.

protected $settings = array(
    'logo' => array(
          'type' => 'logo',
          'path' => 'assets/logo.png'
     ),

     'message' => array(
          'type' => 'string',
          'label' => 'Message'
     )
);

The array contains a name for each setting as a key. The values are arrays containing the required meta data.

Supported types are:

• logo
• string
• html
• choice
• relevance
• info

Besides type a number of other keys are available:

• label, defines a label (use English, the label specified here will be passed through the translation functions)
• default, defines a value to show if no value is specified.
• current, defines the current value.
• readOnly, specifies the setting is read only.

Een voorbeeld met alle huidige instellingen : exampleSettings

Lezen en schrijven

It's possible to read and write plugin settings directly from your plugin code.

Voorbeeld:

$mySetting = $this->get('mySetting');
$this->set('mySetting', $mySetting + 1);

You can get a default value if the setting happens to be null:

$mySetting = $this->get('mySetting', null, null, 10);  // 10 is standaardwaarde

Events

Plugins subscribe to events and can interact with LimeSurvey when the event is fired. For a list of currently available events check Plugin events.

API

Plugins should only extend LimeSurvey via its "public" API. This means that directly using classes found in the source code is a bad practice. Though we can't force you not to, you risk having a broken plugin with every minor update we do.

As much as possible interact with LimeSurvey only via methods described here. Same as for events.

The API object is available via $this->api when extending from PluginBase, otherwise you can get it from the PluginManager instance that is passed to your plugins' constructor.

New functions can be added to the API object upon request.

Lokalisatie (nog niet beschikbaar)

It's possible for plugins to add their own locale files. File format used is .mo, same as core translations. The files must be stored in

<plugin root folder>/locale/<language>/<language>.mo

where "<language>" is a two letter word like "de" or "fr".

To use the specific locale file, use the plugin function gT:

$this->gT("A plugin text that needs to be translated");

If the given string can't be found in the plugin specific locale file, the function will look in the core locale files. So it's safe to use strings like "Cancel":

$this->gT("Cancel");  // Will be translated even if "Cancel" is not in the plugin locale file

If you are using views together with your plugin, you should use

$plugin->gT("Translate me");

to do plugin specific translation in your view.

Logging (nog niet beschikbaar)

If you want to log something from your plugin, just write

$this->log("Your message");

The default logging level is trace, but you can give another log level as an optional second argument:

$this->log("Something went wrong!", CLogger::LEVEL_ERROR);

The log file can be found in folder

<limesurvey root folder>/tmp/runtime/plugin.log

Your plugin name is automatically used as category. A nice way to see only the errors from your plugin is using grep (on Linux):

$ tailf tmp/runtime/plugin.log | grep <your plugin name>

Speciale plugins

• Authentication plugin development
• Export plugin development

Beschikbare plugins

• Authentication plugins
• Audit log
• CintLink
• Available third party plugins

Handleiding

This step-by-step tutorial shows how to create a plugin that sends a post request on every survey response submission. The tutorial shows you how to create and save global and per-survey settings, how to register events and more.