Authentication

The core of the authentication system is based on Pillar Server. That's where the user accounts are. The authentication flow can happen on a dedicated endpoint (local authentication) or via a 3rd party OAuth service. This is a more complex scenario, which involves setting up Pillar Server and Pillar Web so that they act as a single OAuth client.

Local authentication

OAuth authentication

OAuth subclient authentication

How do we generate a token?

The generation of a token can be triggered in a couple of ways after a correct user identification:

  • OAuth token obtained via Pillar Web
  • Local account (starting from an encrypted password)

Token validation

On the Pillar Server level, since we are providing a stateless RESTful API, we authenticate using a base64 encoded token in the header of each request. We check like this:

@app.before_request
def validate_token_at_every_request():
    validate_token()

Where validate_token() validates the token provided in the request and populates the current_user flask.g object, so that permissions and access to a resource can be defined from it.

When the token is successfully validated, we set g.current_user to contain the user information, otherwise it is set to None.

This happens at every request.