torranca/simple-passport-github-oauth2

express-4.x-google-oauth2-example

This example illustrates how to use Express 4.x and Passport to sign users in with Google. Use this example as a starting point for your own web applications.

Quick Start

To get started with this example, clone the repository and install the dependencies.

$ git clone [email protected]:passport/express-4.x-google-oauth2-example.git
$ cd express-4.x-google-oauth2-example
$ npm install

This example requires credentials from Google, which can be obtained by setting up a project in Google APIs console. The redirect URI of the OAuth client should be set to: http://localhost:3000/auth/github/callback

Once credentials have been obtained, create a .env file and add the following environment variables:

GOOGLE_CLIENT_ID={{INSERT_CLIENT_ID_HERE}}
GOOGLE_CLIENT_SECRET={{INSERT_CLIENT_SECRET_HERE}}

Start the server.

$ npm start

Navigate to http://localhost:3000.

Overview

This example illustrates how to use Passport and the passport-google-oauth20 strategy within an Express application to sign users in with Google.

The example builds upon the scaffolding created by Express generator, and uses EJS as a view engine and plain CSS for styling. This scaffolding was generated by executing:

$ express --view ejs express-4.x-google-oauth2-example

The example uses SQLite for storing user accounts. SQLite is a lightweight database that works well for development, including this example.

Added to the scaffolding are files which add authentication to the application.

• boot/db.js

  This file initializes the database by creating the tables used to store user accounts and credentials.

• boot/auth.js

  This file initializes Passport. It configures the Google strategy and supplies the serialization functions used for session management.

• routes/auth.js

  This file defines the routes used for authentication. In particular, there are three routes used to authenticate with Google:

  • GET /login

    This route renders a page that prompts the user to sign in with Google.

  • GET /login/federated/accounts.google.com

    This route begins the authentication sequence by redirecting the user to Google.

  • POST /auth/github/callback

    This route completes the authentication sequence when Google redirects the user back to the application. When a new user signs in, a user account is automatically created and their Google account is linked. When an existing user returns, they are signed in to their linked account.

License

The Unlicense