All tags/Diagram

Signing in with a provider

A sequence diagram - lifelines, numbered messages, replies dashed, an alt frame with its else and a note.

1 The tag diagram/login.pad pad

{diagram type='sequence', title='OAuth sign-in'}
  actor U as User
  participant B as Browser
  participant A as App
  participant P as Provider
  autonumber
  U ->> B: Sign in
  B ->> P: Authorize
  P -->> B: Redirect with a code
  B ->> A: GET /callback
  A ->> P: Exchange the code
  alt Code is valid
    P -->> A: Access token
    A -->> B: Signed in
  else Expired
    A -->> B: Try again
  end
  Note over A,P: The token never reaches the browser
{/diagram}

2 The result rendered on the server