Re: Web Service Implementation

http://docs.moodle.org/dev/Web_services

How it works

This simple example will give you an idea of how our web services infrastructure works.

1. The client sends a username and password to the web service login script.
2. The script returns a token for that user account.
3. The client calls a particular web service function on a protocol server including the token .
4. The protocol server uses the token to check that the user can call the function.
5. The protocol server call the matching external function, located in a externallib.php file inside the relevant module.
6. The external function checks that the current user has_capability to do this operation.
7. The external function calls the matching Moodle core function (in lib.php usually).
8. The core function can return a result to the external function.
9. The external function will return a result to the protocol server.
10. The protocol server returns the result to the client.