How to Integrate Lovable with Google Classroom

Before storing any credentials in Lovable, you need to set up a Google Cloud project with the Classroom API enabled and create the appropriate credentials. Go to console.cloud.google.com and sign in. If you do not have a project, click 'Select a project' → 'New Project', give it a name, and click 'Create'. Once in your project, navigate to 'APIs & Services' → 'Library'. Search for 'Google Classroom API' and click on it. Click 'Enable'. For OAuth2 credentials (used when individual teachers authorize access to their own classes): go to 'APIs & Services' → 'Credentials'. Click 'Create Credentials' → 'OAuth 2.0 Client ID'. If prompted to configure the OAuth consent screen, click through the setup (choose 'Internal' for Google Workspace apps, 'External' for others). Set Application type to 'Web application'. Add your Lovable app's deployed URL as an Authorized redirect URI, plus https://[project-ref].supabase.co/functions/v1/google-classroom-auth/callback for the Edge Function callback. Download the credentials JSON file — you will need the client_id and client_secret values. For service account credentials (used for domain-wide access): click 'Create Credentials' → 'Service Account'. Name it, click 'Create and Continue', skip role assignment for now, and click 'Done'. Click on the service account you just created, go to 'Keys' tab, click 'Add Key' → 'Create New Key' → 'JSON'. Download the JSON key file. For domain-wide delegation (needed to access data across all classrooms in a Google Workspace domain): take note of the service account's client ID (numeric, found in the JSON key file under client_id). Your Google Workspace admin must go to admin.google.com → Security → API Controls → Domain-Wide Delegation → Add new, enter the client ID, and add the scopes: https://www.googleapis.com/auth/classroom.courses.readonly, https://www.googleapis.com/auth/classroom.rosters.readonly, https://www.googleapis.com/auth/classroom.coursework.students.readonly.

With your Google Cloud credentials ready, store them in Lovable's Cloud → Secrets panel. These encrypted environment variables will be accessed by your Edge Function via Deno.env.get() and are never exposed to client-side code. Click the '+' icon at the top of the Lovable editor to open the Cloud panel. Click the Secrets tab. Click 'Add new secret' and add the following (choose the set that matches your credential approach): For OAuth2 client credentials: - GOOGLE_CLIENT_ID — the client_id from your downloaded OAuth2 credentials JSON - GOOGLE_CLIENT_SECRET — the client_secret from your downloaded OAuth2 credentials JSON - GOOGLE_REDIRECT_URI — your Edge Function callback URL: https://[project-ref].supabase.co/functions/v1/google-classroom-auth/callback For service account credentials: - GOOGLE_SERVICE_ACCOUNT_JSON — paste the entire contents of the service account JSON key file as a single-line string (use a JSON minifier to remove whitespace) - GOOGLE_WORKSPACE_DOMAIN — your school's Google Workspace domain (e.g., myschool.edu) — needed for domain-wide impersonation To find your project reference, go to the Cloud tab → Database and look at the Supabase URL shown there — it contains your project reference in the format [project-ref].supabase.co. Service account JSON keys are long — typically 2,000-3,000 characters. Paste the entire minified JSON string as the secret value. Lovable's Secrets panel accepts large values. Verify the stored value starts with {"type":"service_account" when you hover over the secret (the panel shows the first few characters).

Now create the Edge Function that authenticates with Google and proxies Classroom API requests. This function accepts requests from your Lovable frontend, handles OAuth2 token generation (using either service account JWT auth or stored user access tokens), and forwards calls to the Google Classroom API. Paste this prompt into Lovable's chat: 'Create a Supabase Edge Function at supabase/functions/google-classroom-api/index.ts that proxies Google Classroom API requests. The function should: (1) Accept a POST request with body { endpoint: string, method: string, accessToken: string }. (2) Call https://classroom.googleapis.com/{endpoint} with the Authorization: Bearer {accessToken} header. (3) Return the Google Classroom API response with CORS headers. For service account auth, also accept a { serviceAccountMode: true, impersonateEmail: string } option that uses the GOOGLE_SERVICE_ACCOUNT_JSON secret to generate a JWT and obtain an access token from Google before making the API call.' The Google Classroom API base URL is https://classroom.googleapis.com/v1. Common endpoints: /courses (list all courses), /courses/{id}/students (student roster), /courses/{id}/courseWork (assignments), /courses/{id}/courseWork/{cwId}/studentSubmissions (submissions). For service account authentication, you need to create a JWT signed with the service account private key and exchange it for an access token at https://oauth2.googleapis.com/token. This is more complex than simple API key auth — the JWT must include the correct scopes, expiry time, and be signed with RS256 using the private key from the service account JSON. Deno has the Web Crypto API built in for this purpose.

1// supabase/functions/google-classroom-api/index.ts
2const corsHeaders = {
3  'Access-Control-Allow-Origin': '*',
4  'Access-Control-Allow-Headers': 'authorization, x-client-info, apikey, content-type',
5};
6
7Deno.serve(async (req) => {
8  if (req.method === 'OPTIONS') {
9    return new Response('ok', { headers: corsHeaders });
10  }
11
12  try {
13    const { endpoint, method = 'GET', accessToken, pageToken, body: requestBody } = await req.json();
14
15    if (!accessToken) {
16      return new Response(
17        JSON.stringify({ error: 'Missing accessToken' }),
18        { status: 401, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
19      );
20    }
21
22    let url = `https://classroom.googleapis.com/v1/${endpoint}`;
23    if (pageToken) {
24      url += `${url.includes('?') ? '&' : '?'}pageToken=${encodeURIComponent(pageToken)}`;
25    }
26
27    const fetchOptions: RequestInit = {
28      method,
29      headers: {
30        'Authorization': `Bearer ${accessToken}`,
31        'Content-Type': 'application/json',
32      },
33    };
34
35    if (requestBody && method !== 'GET') {
36      fetchOptions.body = JSON.stringify(requestBody);
37    }
38
39    const response = await fetch(url, fetchOptions);
40    const data = await response.json();
41
42    return new Response(JSON.stringify(data), {
43      status: response.status,
44      headers: { ...corsHeaders, 'Content-Type': 'application/json' },
45    });
46  } catch (error) {
47    return new Response(
48      JSON.stringify({ error: error.message }),
49      { status: 500, headers: { ...corsHeaders, 'Content-Type': 'application/json' } }
50    );
51  }
52});

For teacher-facing apps where individual teachers authorize access to their own Google Classroom data, you need to implement the OAuth2 authorization code flow. This allows teachers to click 'Connect Google Classroom' in your Lovable app, authorize access in Google's consent screen, and have their access token stored securely for future API calls. Paste this prompt into Lovable's chat to generate the OAuth flow: 'Create an OAuth2 flow for Google Classroom: (1) A Connect Google Classroom button that redirects teachers to https://accounts.google.com/o/oauth2/v2/auth with client_id from GOOGLE_CLIENT_ID, redirect_uri from GOOGLE_REDIRECT_URI, scope as https://www.googleapis.com/auth/classroom.courses.readonly https://www.googleapis.com/auth/classroom.rosters.readonly https://www.googleapis.com/auth/classroom.coursework.students.readonly, response_type as code, and access_type as offline. (2) A callback Edge Function at supabase/functions/google-classroom-auth/index.ts that exchanges the authorization code for tokens at https://oauth2.googleapis.com/token and stores the access_token and refresh_token in the Supabase user profile. (3) A token refresh mechanism that calls the token endpoint with the refresh_token when the access_token expires.' Google access tokens expire after 1 hour. The refresh_token does not expire (unless the user revokes access) and can be used to get a new access_token. Store both in your Supabase user profiles table in columns google_access_token, google_refresh_token, and google_token_expires_at. Before each API call, check if the access token is expired and refresh it automatically. For security, never store the raw access token on the frontend — only in Supabase. When the frontend needs to call the Classroom API, it calls your Edge Function, which retrieves the stored token from Supabase using the Supabase service role key and injects it into the Google API call.

With authentication working, build the React components that display Google Classroom data. The core dashboard shows a teacher's courses, and clicking a course reveals its assignments and student roster. Paste this prompt into Lovable's chat: 'Create a TeacherDashboard React component. On load, call the google-classroom-api Edge Function with endpoint "courses?courseStates=ACTIVE", passing the teacher's stored access token from their Supabase profile. Display courses in a grid: course name, section, enrollment code, and number of students. Add a student count by calling "courses/{id}/students" for each course. Clicking a course opens a detail view showing: (1) a roster table of student names and emails from the courses/{id}/students endpoint, (2) a list of active assignments from courses/{id}/courseWork?courseWorkStates=PUBLISHED sorted by dueDate, (3) for each assignment, a submission count vs total students fetched from courses/{id}/courseWork/{cwId}/studentSubmissions?states=TURNED_IN.' The Google Classroom API student submission states are: NEW (not viewed), CREATED (started), TURNED_IN (submitted), RETURNED (graded and returned), RECLAIMED_BY_STUDENT (recalled after submission). For tracking purposes, TURNED_IN and RETURNED both indicate submission. For the assignment list, display due dates in the teacher's local timezone. Google Classroom dueDate objects use a specific format: { year, month, day } and dueTime: { hours, minutes }. Combine these into a JavaScript Date object for display. Be aware of API quota limits: the Google Classroom API has a default quota of 500 read requests per 100 seconds per project. If you are loading many courses and their assignments simultaneously, implement a queue or sequential loading pattern rather than firing all requests in parallel.