[PLT-28] Google Authentication (#1099)

* created /google-auth route

* integrate /google-auth route with frontend

* hide secret credentials

Author: Avdhesh-Varshney

.gitignore

@@ -15,8 +15,6 @@ __pycache__\
 *.ini
 .ipynb_checkpoints/
 
-# Secret files
-kaggle.json
 
 
 ################################################################# WEB DEVELOPMENT #################################################################
@@ -137,3 +135,8 @@ typings
 # typescript
 *.tsbuildinfo
 next-env.d.ts
+
+
+################################################################# Secret files #################################################################
+kaggle.json
+firebase-adminsdk.json

backend/Controllers/auth.controller.js

@@ -1,4 +1,9 @@
 import bcrypt from "bcrypt";
+
+import admin from "firebase-admin";
+import { getAuth } from "firebase-admin/auth";
+import serviceAccountKey from "../firebase-adminsdk.json" assert { type: "json" };
+
 import User from "../Models/user.model.js";
 import { formatDataToSend, generateUsername, emailRegex, passwordRegex } from "../utils/helpers.js";
 
@@ -34,6 +39,8 @@ export const login = async (req, res) => {
         const user = await User.findOne({ "personal_info.email": email });
         if (!user) return res.status(404).json({ error: "Email not found" });
 
+        if (user.google_auth) return res.status(403).json({ "error": "This email was signed up with google. Please log in with google to access the account." });
+
         const isMatch = await bcrypt.compare(password, user.personal_info.password);
         if (!isMatch) return res.status(401).json({ error: "Incorrect password" });
 
@@ -42,3 +49,60 @@ export const login = async (req, res) => {
         return res.status(500).json({ error: "Internal Server Error" });
     }
 };
+
+// Google Authorization using Firebase
+
+admin.initializeApp({
+    credential: admin.credential.cert(serviceAccountKey)
+})
+
+export const googleAuth = async (req, res) => {
+    let { access_token } = req.body;
+
+    try {
+        getAuth()
+            .verifyIdToken(access_token)
+            .then(async (decodedUser) => {
+
+                let { email, name } = decodedUser;
+
+                let user = await User.findOne({ "personal_info.email": email }).select("personal_info.fullname personal_info.username personal_info.profile_img google_auth").then((u) => {
+                    return u || null;
+                })
+                    .catch(err => {
+                        return res.status(500).json({ "error": err.message });
+                    })
+
+                if (user) {
+                    // login
+                    if (!user.google_auth) {
+                        return res.status(403).json({ "error": "This email was signed up without google. Please log in with password to access the account." });
+                    }
+                } else {
+                    //signup
+                    let username = await generateUsername(email);
+                    user = new User({
+                        personal_info: {
+                            fullname: name,
+                            email,
+                            username
+                        },
+                        google_auth: true
+                    })
+                    await user.save().then((u) => {
+                        user = u;
+                    })
+                        .catch(err => {
+                            return res.status(500).json({ "error": err.message });
+                        })
+                }
+
+                return res.status(200).json(formatDataToSend(user));
+            })
+            .catch(err => {
+                return res.status(500).json({ "error": err.message });
+            })
+    } catch (err) {
+        return res.status(500).json({ "error": err.message });
+    }
+}

backend/Routes/api/auth.routes.js

@@ -1,9 +1,10 @@
 import express from "express";
-import { signup, login } from "../../Controllers/auth.controller.js";
+import { signup, login, googleAuth } from "../../Controllers/auth.controller.js";
 
 const authRoutes = express.Router();
 
 authRoutes.post("/signup", signup);
 authRoutes.post("/login", login);
+authRoutes.post("/google-auth", googleAuth);
 
 export default authRoutes;