Development:External services description
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Jerome's proposal
- Database table should only contain data that can be manage by administrator
- All the web services description should be in a array into each external.php file
- a cron job browse all external file, check the description and update the database (if functions/services disappeared or are created)
external_functions table
List of external functions. Created automatically by parsing of external files.
Field | Type | Default | Description |
---|---|---|---|
id | int(10) | auto-incrementing | |
name | varchar(150) | Name of function - Appears on the admin page | |
enabled | int(1) | function enabled, function might be disabled for security reasons - The only field editable by administrator ! | |
phpfile | varchar(255) | location where function defined - Needed for identifying |
external_services table
Service is defined as a group of functions.
Field | Type | Default | Description |
---|---|---|---|
id | int(10) | auto-incrementing | |
name | varchar(150) | Name of service (gradeexport_xml_export, mod_chat_export) - appears on the admin page | |
enabled | int(1) | service enabled, for security reasons some services may be disabled - The only editable field by the admin | |
custom | int(1) | 0 | Custom local service, created manually by admin or some other way (CAN BE updated automatically during the cron job => function not existing get removed). This field is useful if we want to implement an admin page where the admin selects some functions from a list of all external functions. Note: we probably need a button to desactivate all services in once. |
external_services_functions table
Specifies functions used by services.
Field | Type | Default | Description |
---|---|---|---|
id | int(10) | auto-incrementing | |
externalserviceid | int(10) | foreign key, reference external_services.id | |
externalfunctionid | int(10) | foreign key, reference external_functions.id |
PHP array description
$this->descriptions['function_name'] = array( 'params' => array('params_name'=> PARAM_STRING),
'optionalparams' => array( ),
'return' => array('list:param_1' =>
array('attribut_1' => PARAM_INT,
'attribut_2' => PARAM_STRING,
'attribut_3' => PARAM_INT)));
Explanation:
- base is:
$this->descriptions['function_name'] = array( 'params' => array(),
'optionalparams' => array( ),
'return' => array());
- when a param/return is a list so it should be called 'list:param_name'
- when a param/return is not a list so it's either a primary type (e.g. PARAM_STRING), either a object (e.g. array)
- params and optionalparams have to follow the exact order of the function
- PARAM_RAW has to be replaced by the correct type (cannot be array)
Way to fill the database tables
A cron job update the tables
Return values are filtered by the servers
External function should be able to return whatever they want. Each server should be looking at the web services description and return the expected values.