How to Integrate Replit with Google Classroom

1// server.js — Google Classroom OAuth + API server
2const express = require('express');
3const session = require('express-session');
4const { google } = require('googleapis');
5
6const app = express();
7app.use(express.json());
8app.use(session({
9  secret: process.env.SESSION_SECRET,
10  resave: false,
11  saveUninitialized: false
12}));
13
14function getOAuthClient() {
15  return new google.auth.OAuth2(
16    process.env.GOOGLE_CLIENT_ID,
17    process.env.GOOGLE_CLIENT_SECRET,
18    process.env.GOOGLE_REDIRECT_URI
19  );
20}
21
22const SCOPES = [
23  'https://www.googleapis.com/auth/classroom.courses.readonly',
24  'https://www.googleapis.com/auth/classroom.coursework.me.readonly',
25  'https://www.googleapis.com/auth/classroom.rosters.readonly'
26];
27
28// Step 1: redirect to Google consent screen
29app.get('/auth/login', (req, res) => {
30  const oauth2Client = getOAuthClient();
31  const authUrl = oauth2Client.generateAuthUrl({
32    access_type: 'offline',  // Get refresh token
33    scope: SCOPES,
34    prompt: 'consent'
35  });
36  res.redirect(authUrl);
37});
38
39// Step 2: handle the callback from Google
40app.get('/auth/google/callback', async (req, res) => {
41  const { code } = req.query;
42  if (!code) return res.status(400).send('Missing authorization code');
43
44  try {
45    const oauth2Client = getOAuthClient();
46    const { tokens } = await oauth2Client.getToken(code);
47    req.session.tokens = tokens;
48    res.redirect('/courses');  // Redirect to app after login
49  } catch (err) {
50    console.error('OAuth callback error:', err.message);
51    res.status(500).send('Authentication failed');
52  }
53});
54
55// Middleware: check authentication
56function requireAuth(req, res, next) {
57  if (!req.session.tokens) return res.redirect('/auth/login');
58  next();
59}
60
61// Step 3: use the token to call Google Classroom API
62app.get('/courses', requireAuth, async (req, res) => {
63  try {
64    const oauth2Client = getOAuthClient();
65    oauth2Client.setCredentials(req.session.tokens);
66
67    const classroom = google.classroom({ version: 'v1', auth: oauth2Client });
68    const response = await classroom.courses.list({
69      pageSize: 20,
70      courseStates: ['ACTIVE']
71    });
72
73    const courses = (response.data.courses || []).map(c => ({
74      id: c.id,
75      name: c.name,
76      section: c.section,
77      enrollmentCode: c.enrollmentCode,
78      courseState: c.courseState
79    }));
80
81    res.json({ courses });
82  } catch (err) {
83    console.error('Classroom API error:', err.message);
84    res.status(500).json({ error: err.message });
85  }
86});
87
88// Fetch assignments for a course
89app.get('/courses/:courseId/assignments', requireAuth, async (req, res) => {
90  const { courseId } = req.params;
91  try {
92    const oauth2Client = getOAuthClient();
93    oauth2Client.setCredentials(req.session.tokens);
94
95    const classroom = google.classroom({ version: 'v1', auth: oauth2Client });
96    const response = await classroom.courses.courseWork.list({
97      courseId,
98      pageSize: 50,
99      orderBy: 'dueDate asc'
100    });
101
102    res.json({ assignments: response.data.courseWork || [] });
103  } catch (err) {
104    res.status(500).json({ error: err.message });
105  }
106});
107
108const PORT = process.env.PORT || 3000;
109app.listen(PORT, '0.0.0.0', () => {
110  console.log(`Google Classroom server running on port ${PORT}`);
111});

1# app.py — Google Classroom OAuth server in Python
2import os
3import json
4from flask import Flask, session, redirect, url_for, request, jsonify
5from google_auth_oauthlib.flow import Flow
6from googleapiclient.discovery import build
7from google.oauth2.credentials import Credentials
8
9app = Flask(__name__)
10app.secret_key = os.environ['SESSION_SECRET']
11os.environ['OAUTHLIB_INSECURE_TRANSPORT'] = '0'  # Enforce HTTPS in production
12
13SCOPES = [
14    'https://www.googleapis.com/auth/classroom.courses.readonly',
15    'https://www.googleapis.com/auth/classroom.coursework.me.readonly'
16]
17
18def make_flow():
19    return Flow.from_client_config(
20        {
21            'web': {
22                'client_id': os.environ['GOOGLE_CLIENT_ID'],
23                'client_secret': os.environ['GOOGLE_CLIENT_SECRET'],
24                'redirect_uris': [os.environ['GOOGLE_REDIRECT_URI']],
25                'auth_uri': 'https://accounts.google.com/o/oauth2/auth',
26                'token_uri': 'https://oauth2.googleapis.com/token'
27            }
28        },
29        scopes=SCOPES,
30        redirect_uri=os.environ['GOOGLE_REDIRECT_URI']
31    )
32
33@app.route('/auth/login')
34def login():
35    flow = make_flow()
36    auth_url, state = flow.authorization_url(access_type='offline', prompt='consent')
37    session['oauth_state'] = state
38    return redirect(auth_url)
39
40@app.route('/auth/google/callback')
41def callback():
42    flow = make_flow()
43    flow.fetch_token(authorization_response=request.url)
44    creds = flow.credentials
45    session['tokens'] = {
46        'token': creds.token,
47        'refresh_token': creds.refresh_token,
48        'token_uri': creds.token_uri,
49        'client_id': creds.client_id,
50        'client_secret': creds.client_secret,
51        'scopes': list(creds.scopes)
52    }
53    return redirect('/courses')
54
55@app.route('/courses')
56def courses():
57    if 'tokens' not in session:
58        return redirect('/auth/login')
59    creds = Credentials(**session['tokens'])
60    service = build('classroom', 'v1', credentials=creds)
61    result = service.courses().list(pageSize=20, courseStates=['ACTIVE']).execute()
62    return jsonify({'courses': result.get('courses', [])})
63
64if __name__ == '__main__':
65    app.run(host='0.0.0.0', port=3000)