How to enable web services for an external system

Moodle 2.0

This document explains how an administrator can set up a web service that an external system can access.

A brief note about custom web services

There is no such thing as a default web service in Moodle, so anyone looking for one (or for a list of available services) may get rather confused. Instead, you must create a custom service.

Creating a custom service does not mean you are really creating an entirely new web service yourself. You don't have to program anything. Instead, a 'custom web service' just lets you select which of the standard web service functions are available via that service.

This allows you to enable only the specific functions that you need to expose, therefore increasing security. The procedure is included below.

Token authentication method

There is two way for the an external service to authenticate on Moodle. Either with a security key (also call token), either with a username/password. In this chapter we explain how a Moodle administrator set up web service for an external system with a security key.

Enable the web service in Moodle

  Settings block > Site Administration > Advanced features

  Check Enable web services option and Save Changes

Enable a protocol

  Settings block > Site Administration > Plugins > Web services > Manage protocols

  Enable the desired protocol (SOAP, REST, XMLRPC, AMF, ...)

Create a new user

  Settings block > Site Administration > Users > Accounts > Add a new user

  Complete the other fields and select Update profile operation

Enable capabilities to specific user

for protocols

you need to set the activated protocol (webservice/rest:use, webservice/soap:use,...) capability to the specific user.

Create a service with funtions

  Settings block > Site Administration > Plugins > Web services > External Services
  Click on Add new custom service

Add new custom service page

A service is a group of web service functions. By default any user using the web service authentication method will be able to call a service. To restrict a service to some user you need to select the Authorized users option.

  Enter a name, check enable
  Checked authorized users
  Click on Save changes

Add a function to the service

  Settings block > Site Administration > Plugins > Web services > External Services

  Click on the Functions link for the newly created service

Service functions page

  Select Add function operation, then select a function and Save changes

Admin create token for specific user

give the token to the user

The client can connect into Moodle and see the token into his security keys page.

Variant: simple authentication method

This authentication method is a little different from the token one. The client send his username/password instead of a token. All steps are similar except that the administrator doesn't need to create any token and need to process the following steps:

Enable the web service authentication plugin

  Settings block > Site Administration > Plugins > Authentication > Manage authentication

  Enable Web services

Create a new user

this steps is little bit different from the one in the token authentication.

  Settings block > Site Administration > Users > Accounts > Add a new user

  Select Web services option for Choose an authentication method. 
  This user will not be able to log into the site but can access web service.
  Complete the other fields and select Update profile operation