agrison / oauth2

Allows your Martini application to support user login via an OAuth 2.0 backend.

oauth2

Allows your Martini application to support user login via an OAuth 2.0 backend. Requires sessions middleware. Google, Facebook and Github sign-in are currently supported. Once endpoints are provided, this middleware can work with any OAuth 2.0 backend.

Usage

package main

import (
  "github.com/go-martini/martini"
  "github.com/martini-contrib/oauth2"
  "github.com/martini-contrib/sessions"
)

func main() {
  m := martini.Classic()
  m.Use(sessions.Sessions("my_session", sessions.NewCookieStore([]byte("secret123"))))
  m.Use(oauth2.Google(&oauth2.Options{
    ClientId:      "client_id",
    ClientSecret:  "client_secret",
    RedirectURL:   "redirect_url",
    Scopes:        []string{"https://www.googleapis.com/auth/drive"},
    LoginCallback: func(tokens oauth2.Tokens, t *oauth.Transport, s sessions.Session, w http.ResponseWriter, r *http.Request) {
    	fmt.Printf("access token: %s", tokens.Access())
	// Do whatever you want with session, or http stuff like sending additional header/cookies, 
	// or read additional information from request
    },
  }))

  // Tokens are injected to the handlers
  m.Get("/", func(tokens oauth2.Tokens) string {
    if tokens.IsExpired() {
      return "not logged in, or the access token is expired"
    }
    return "logged in"
  })

  // Routes that require a logged in user
  // can be protected with oauth2.LoginRequired handler.
  // If the user is not authenticated, they will be
  // redirected to the login path.
  m.Get("/restrict", oauth2.LoginRequired, func(tokens oauth2.Tokens) string {
    return tokens.Access()
  })

  m.Run()
}

If a route requires login, you can add oauth2.LoginRequired to the handler chain. If user is not logged, they will be automatically redirected to the login path.

m.Get("/login-required", oauth2.LoginRequired, func() ...)

Auth flow

• /login will redirect user to the OAuth 2.0 provider's permissions dialog. If there is a next query param provided, user is redirected to the next page afterwards.
• If user agrees to connect, OAuth 2.0 provider will redirect to /oauth2callback to let your app to make the handshake. You need to register /oauth2callback as a Redirect URL in your application settings.
• /logout will log the user out. If there is a next query param provided, user is redirected to the next page afterwards.

You can customize the login, logout, oauth2callback and error paths:

oauth2.PathLogin = "/oauth2login"
oauth2.PathLogout = "/oauth2logout"
...

Authors

• Burcu Dogan