Special variables

Brai4it modules have some special variables that are described below:

module-metadata: a list that contains properties that provide information about the module. Example:
( "icon" => "sensors" "description" => "Libelium stations" "author" => "Mike" )

All Brain4it managers show a list of the modules that are contained in a server. Each module in that list is displayed with an icon and a label that are set respectively with the icon and description properties of module-metadata.

In addition to these properties any other can be added to provide more information about the module.

All the content of module-metadata is always be visible for everyone.
access-key: a string that contains the key required to access the module data through the REST API. You can find more information about the Brain4it security model in the REST API.
start: a code block that will be executed when module is started. This code is intented to perform initialization tasks and must return as soon as possible. Example:
(do (subscribe_sensor) (open_db_connection) (spawn (eval loop)) )
stop: a code block that will be executed when module is stopped. This code is intented to perform cleanup tasks and must return as soon as possible. Example:
(do (close_db_connection) (unsubscribe_sensor) )
@dashboards: a exterior function that returns a list containing the definitions of all the dashboards offered by this module. Example:
(function (context data) (list "Control panel" => control_dashboard "Activity log" => log_dashboard ) )

The managers call this function every time the user opens the dashboards view.