Gamma Documentation¶

About this Document¶

This document is is aimed at developers looking to use the Gamma API to provide their users with the ability to login with Gamma and/or to fetch data from the Gamma API.

It was written by Cal to demistify how to use and integrate with Gamma after painstakingly figuring out how to do so without proper documentation.

Contributing¶

Contributions to this document are welcome and much appreciated. Contact Cal or digIT to find out how you can help.

The Future¶

In the future this document will be hopefully be hosted on some official place such as the GitHub wiki page for Gamma or on some chalmers.it website.

Introduction¶

What is Gamma?¶

Gamma is the authentication and authorization service developed and used by the IT student division at Chalmers, with the long-term goal of also being adopted by other student divisions at Chalmers.

It is hosted at https://auth.chalmers.it and the source code can be found at cthit/Gamma on GitHub.

Getting Started with Gamma Clients¶

What is a Client?¶

Gamma is built on top of the OAuth 2.0 protocol. A basic understanding of the protocol is recommended but not strictly required to understand this documentation. If you are unfamiliar with it, this article by Auth0 serves as a good starting point.

A client allows access to Gamma through the Client API and Authorization Code flow. It identifies your application in Gamma and is shown to users when authorizing ("logging in to") your service.

Types of clients¶

Gamma has two types of clients, User clients and Official clients.

User Clients¶

A user client can be created by anyone with a Gamma account but is limited compared to an official client. User clients can only access parts of the Info API and can only fetch data from users who have authorized the client.

// TODO: Update what they can access. Can they really access the info API?

As any Gamma user can create a user client caution should be given when authorizing them. That is why a warning is shown to users when authorizing a user client saying who the client belongs to.

Official Clients¶

To do more you must be a Gamma administrator and create an official client. These clients have unrestricted access to the Gamma API and can fetch data from all users.

// TODO: Update access

Super Group Restrictions¶

Official clients can also add Restrictions on which super groups are allowed to authorize the client. Users that are not in any of these groups will see an error screen.