From 72b27113677d551f356fd77564c0ac16efb95f6a Mon Sep 17 00:00:00 2001
From: "Lin, Hung-Shin" <wancat@wancat.cc>
Date: Thu, 5 Oct 2023 13:32:02 +0800
Subject: [PATCH] feat: make social login optional

---
 app/src/components/AuthenticationPart.vue |  9 ++-
 server/src/api/routes/auth.js             | 23 ++++---
 server/src/auth/googleStrategy.js         | 82 ++++++++++++-----------
 server/src/auth/passport.js               | 14 +++-
 server/swagger.yaml                       | 66 ++++++++++++++++++
 5 files changed, 145 insertions(+), 49 deletions(-)

diff --git a/app/src/components/AuthenticationPart.vue b/app/src/components/AuthenticationPart.vue
index 6c22147..5163eca 100644
--- a/app/src/components/AuthenticationPart.vue
+++ b/app/src/components/AuthenticationPart.vue
@@ -1,5 +1,5 @@
 <script setup>
-import { ref } from 'vue'
+import { onMounted, ref } from 'vue'
 import { useRouter } from 'vue-router'
 import { login, register } from '../utils/auth'
 import api from '../utils/api'
@@ -13,6 +13,12 @@ const emailInput = ref(null)
 const password = ref('')
 const errorMessage = ref('')
 
+const availableMethods = ref({})
+onMounted(async () => {
+  const res = await api.get('/auth/available-methods')
+  availableMethods.value = res.data
+})
+
 const success = () => {
   router.push({ name: 'game' })
 }
@@ -172,6 +178,7 @@ const goBack = () => {
         Log in with social account
       </p>
       <a
+        v-if="availableMethods.google"
         class="inline-flex justify-center rounded-lg text-sm font-black py-2 mt-3 bg-icon-google text-text w-full"
         href="/api/v1/auth/google"
       >
diff --git a/server/src/api/routes/auth.js b/server/src/api/routes/auth.js
index 73140ff..d94c3c0 100644
--- a/server/src/api/routes/auth.js
+++ b/server/src/api/routes/auth.js
@@ -1,6 +1,8 @@
 import { Router } from 'express'
 import passport from 'passport'
 
+import enabledMethods from '../../auth/passport.js'
+
 import {
   register,
   checkUsername,
@@ -26,14 +28,19 @@ router.get('/check-username', checkUsername)
 
 router.get('/check-session', checkSession)
 
-router.get('/google', passport.authenticate('google'))
+router.get('/available-methods', (req, res) => {
+  res.json(enabledMethods)
+})
 
-router.get(
-  '/google/callback',
-  passport.authenticate('google', {
-    successRedirect: '/',
-    failureRedirect: '/login',
-  })
-)
+if (enabledMethods.google) {
+  router.get('/google', passport.authenticate('google'))
+  router.get(
+    '/google/callback',
+    passport.authenticate('google', {
+      successRedirect: '/',
+      failureRedirect: '/login',
+    })
+  )
+}
 
 export default router
diff --git a/server/src/auth/googleStrategy.js b/server/src/auth/googleStrategy.js
index f901c43..3a6e63a 100644
--- a/server/src/auth/googleStrategy.js
+++ b/server/src/auth/googleStrategy.js
@@ -3,48 +3,52 @@ import GoogleStrategy from 'passport-google-oidc'
 import config from '../config.js'
 import User from '../models/user.js'
 
-console.log('Google config:', config.google)
+function verify(issuer, profile, cb) {
+  console.log('Get a google login:', profile)
 
-export default new GoogleStrategy(
-  {
-    clientID: config.google.clientID,
-    clientSecret: config.google.clientSecret,
-    callbackURL: '/api/v1/auth/google/callback',
-    scope: ['profile', 'email'],
-  },
-  function verify(issuer, profile, cb) {
-    console.log('Get a google login:', profile)
+  process.nextTick(async () => {
+    const email = profile.emails[0]?.value
+    if (!email) {
+      cb(new Error('No email found'))
+      return
+    }
 
-    process.nextTick(async () => {
-      const email = profile.emails[0]?.value
-      if (!email) {
-        cb(new Error('No email found'))
-        return
+    let user = await User.findOne({ 'google.id': profile.id })
+    if (!user) {
+      user = await User.findOne({ email })
+      const google = {
+        id: profile.id,
+        displayName: profile.displayName,
       }
-
-      let user = await User.findOne({ 'google.id': profile.id })
+      console.log('Existing user:', user)
       if (!user) {
-        user = await User.findOne({ email })
-        const google = {
-          id: profile.id,
-          displayName: profile.displayName,
-        }
-        console.log('Existing user:', user)
-        if (!user) {
-          user = new User({
-            email,
-            google,
-          })
-        } else if (user.google?.id) {
-          cb(new Error('Email already used and binded to another account'))
-          return
-        } else {
-          user.google = google
-        }
-        await user.save()
+        user = new User({
+          email,
+          google,
+        })
+      } else if (user.google?.id) {
+        cb(new Error('Email already used and binded to another account'))
+        return
+      } else {
+        user.google = google
       }
+      await user.save()
+    }
 
-      cb(null, user)
-    })
-  }
-)
+    cb(null, user)
+  })
+}
+
+const enabled = config.google.clientID && config.google.clientSecret
+
+export default enabled
+  ? new GoogleStrategy(
+      {
+        clientID: config.google.clientID,
+        clientSecret: config.google.clientSecret,
+        callbackURL: '/api/v1/auth/google/callback',
+        scope: ['profile', 'email'],
+      },
+      verify
+    )
+  : null
diff --git a/server/src/auth/passport.js b/server/src/auth/passport.js
index 682fd86..e2f4525 100644
--- a/server/src/auth/passport.js
+++ b/server/src/auth/passport.js
@@ -5,7 +5,17 @@ import googleStrategy from './googleStrategy.js'
 
 passport.use(passwordStrategy)
 passport.use(jwtStrategy)
-passport.use(googleStrategy)
+
+const enabledMethods = {
+  local: true,
+  google: googleStrategy !== null,
+}
+
+console.log('Enabled login methods', enabledMethods)
+
+if (enabledMethods.google) {
+  passport.use(googleStrategy)
+}
 
 passport.serializeUser((user, done) => {
   process.nextTick(() => {
@@ -22,3 +32,5 @@ passport.deserializeUser((user, done) => {
     done(null, user)
   })
 })
+
+export default enabledMethods
diff --git a/server/swagger.yaml b/server/swagger.yaml
index c3c6bb7..b9f09b3 100644
--- a/server/swagger.yaml
+++ b/server/swagger.yaml
@@ -319,6 +319,30 @@ paths:
                     type: string
                     example: Username is already taken
 
+  /auth/available-methods:
+    get:
+      summary: Get available login methods
+      responses:
+        '200':
+          description: Available login methods
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  local:
+                    type: boolean
+                    example: true
+                  github:
+                    type: boolean
+                    example: true
+                  google:
+                    type: boolean
+                    example: true
+                  facebook:
+                    type: boolean
+                    example: true
+
   /auth/check-session:
     get:
       summary: Check if the session is valid
@@ -334,6 +358,36 @@ paths:
                     type: boolean
                     example: true
 
+  /auth/google:
+    get:
+      summary: Initiate OAuth2 login with Google
+      operationId: initiateOAuth
+      security:
+        - GoogleOAuth: []
+      responses:
+        302:
+          description: Redirect to Google's OAuth 2.0 authorization endpoint
+        500:
+          description: Internal Server Error
+  /auth/google/callback:
+    get:
+      summary: OAuth2 callback endpoint
+      operationId: oauthCallback
+      parameters:
+        - name: code
+          in: query
+          description: Authorization code from Google
+          required: true
+          schema:
+            type: string
+      responses:
+        200:
+          description: Successful Operation
+        400:
+          description: Bad Request
+        500:
+          description: Internal Server Error
+
   /quests:
     get:
       summary: Get quests list
@@ -571,3 +625,15 @@ components:
       type: apiKey
       in: cookie
       name: connect.sid
+
+    GoogleOAuth:
+      type: oauth2
+      flows:
+        authorizationCode:
+          authorizationUrl: https://accounts.google.com/o/oauth2/auth
+          tokenUrl: https://accounts.google.com/o/oauth2/token
+          scopes:
+            # Define your scopes here
+            openid: OpenID
+            profile: User profile
+            email: User email