Ticklers

From FreemedDeveloperWiki, the FreeMED developers' Wiki.

Ticklers are autonomous events which can occur seperately from user sessions. They are meant to be called by an external cron job (or other regular event) via the XML-RPC mechanism. This gives FreeMED the abilities that it would have if it were a standalone daemon, instead of a web service.

Calling Ticklers

All ticklers on the system can be called with the XML-RPC call:

 FreeMED.Tickler.call ( [hash of parameters] )

This will return a CR-seperated list of messages, including any error messages which are generated by the ticklers.

Calling ticklers with the hash value interval will usually cause those which are interval-specific (such as every hour, et cetera) to not execute unless that value is specified correctly.

Possible interval values are:

• hourly
• weekly
• monthly
• yearly

Creating Ticklers

To create a tickler, either take an existing module, or create another one. In its constructor, add a handler for the tickler method. (Please note that the method doesn't have to be called tickler ... I just call it that in this example ... )

 $this->_SetHandler('Tickler', 'tickler');

Then create the actual method:

 function tickler ( $params = NULL ) {
     if ($params['interval'] == 'hourly') {
         // do some action here
         // ...
         // ...
         if ($is_done_without_error) {
             // Either use:
             print "MyModule tickler: Done without error!";
             // or
             return "MyModule tickler: Done without error!";
         }
     }
 } // end method tickler