Add Support for google and other provider login

Author: pratapaprasanna

authenticator/adapters/db/api.py

@@ -14,10 +14,14 @@ def get_all_users(self):
             output.append({'name': user['name'], 'email': user['email']})
         return jsonify({'result': output})
 
-    def add_users(self, name, email):
+    def add_users(self, name, email, provider):
         try:
             collection = self.client.db['users']
-            collection_id = collection.insert({'name': name, 'email': email})
-            return jsonify({'result': collection_id})
+            count = collection.count_documents({'email': email})
+            if count == 0:
+                collection_id = collection.insert(
+                    {'name': name, 'email': email, 'provider': provider})
+                return jsonify({'result': str(collection_id)})
+            return jsonify({'result': "User already signed up"})
         except Exception:
             print("ISSUE")

authenticator/adapters/login/README.md

@@ -0,0 +1,5 @@
+To login via Google visit 
+```bash
+127.0.0.1:5000/login/google
+```
+in the browser. provided the mongo docker container is up and running to enter

authenticator/adapters/login/__init__.py

@@ -0,0 +1,7 @@
+from authlib.integrations.flask_client import OAuth
+
+
+class loginManager(object):
+
+    def __init__(self, app):
+        self.auth = OAuth(app)

authenticator/adapters/login/loginmanager.py

@@ -1,28 +1,79 @@
+from configparser import ConfigParser
+
 from flask import Flask
 from flask import jsonify
-from flask import request
+from flask import request, url_for, redirect, session
+from flask_login import logout_user
 
 from authenticator.adapters.db import api as db_api
-from authenticator import config
+from authenticator.adapters.login import loginmanager
+
+config = ConfigParser()
+config.read("config.ini")
+
+database = config.get('default', 'db')
+host = config.get('default', 'db_host')
+port = config.get('default', 'db_port')
 
 app = Flask(__name__)
+app.config['MONGO_URI'] = f'mongodb://{host}:{port}/{database}'
+app.config['SECRET_KEY'] = "b9dd1b2f"
+app.config['GOOGLE_CLIENT_ID'] = config.get('google-oauth', 'client_id')
+app.config['GOOGLE_CLIENT_SECRET'] = config.get(
+    'google-oauth', 'client_secret')
 
-app.config['MONGO_DBNAME'] = config.DATABASE
-app.config['MONGO_URI'] = f'mongodb://{config.DB_HOST}:{config.DB_PORT}/{config.DATABASE}'
 
 db_obj = db_api.MongoAdapters(app)
+login_obj = loginmanager.loginManager(app)
 
 
 @app.route('/users', methods=['GET'])
 def get_users():
     return db_obj.get_all_users()
 
 
-@app.route('/add', methods=['POST'])
-def add_users():
-    name = request.json['name']
-    email = request.json['email']
-    return db_obj.add_users(name, email)
+@app.route('/', methods=['GET'])
+def index():
+    return "Welcome to nomad Authenticator."
+
+
+def add_users(name, email, provider):
+    return db_obj.add_users(name, email, provider)
+
+
+@app.route('/login/google')
+def google_login():
+    login_obj.auth.register(
+        name='google',
+        client_id=app.config["GOOGLE_CLIENT_ID"],
+        client_secret=app.config["GOOGLE_CLIENT_SECRET"],
+        access_token_url='https://accounts.google.com/o/oauth2/token',
+        access_token_params=None,
+        authorize_url='https://accounts.google.com/o/oauth2/auth',
+        authorize_params=None,
+        api_base_url='https://www.googleapis.com/oauth2/v1/',
+        # This is only needed if using openId to fetch user info
+        userinfo_endpoint='https://openidconnect.googleapis.com/v1/userinfo',
+        client_kwargs={'scope': 'openid email profile'},
+    )
+    google = login_obj.auth.create_client('google')
+    redirect_uri = url_for('google_authorize', _external=True)
+    return google.authorize_redirect(redirect_uri)
+
+
+@app.route('/login/google/authorize')
+def google_authorize():
+    google = login_obj.auth.create_client('google')
+    token = google.authorize_access_token()
+    resp = google.get('userinfo').json()
+    return add_users(resp['name'], resp['email'], "google")
+
+
+@app.route('/logout')
+def user_logout():
+    for key in list(session.keys()):
+        session.pop(key)
+    return redirect('/')
 
 
 if __name__ == '__main__':

authenticator/app.py

@@ -0,0 +1,10 @@
+[default]
+db = nomad
+db_host = localhost
+db_port = 27017
+app_port = 5000
+
+[google-oauth]
+name = google
+client_id = 1034883885605-gvj78f1cg3urngprb0jjfr3p0olqh8tr.apps.googleusercontent.com
+client_secret = jPbO8Hxm20DkefDqmD4EyhCs