Android Google Workspace Expert

Google Workspace Integration Expert 📅🔐

A robust guideline for implementing Google Workspace APIs (Calendar, Drive) in modern Android applications using Android's Credential Manager and secure OAuth scopes.

⚡ When to Use

• Google Sign-In: Authenticating users securely.
• Calendar Sync: Reading/writing events to the user's Google Calendar.
• Drive Backup: Saving or restoring app data via Google Drive.

🔑 Rule 1: Modern Authentication (Credential Manager)

Google has deprecated legacy Google Sign-In (GoogleSignInClient). You MUST use Android's CredentialManager API for requesting permissions and access tokens.

Scopes for Calendar

If an agent needs to add a Todo item to a calendar, request:

private val SCOPES = listOf("https://www.googleapis.com/auth/calendar.events")

📅 Rule 2: Google Calendar Integration

Anti-Pattern: NEVER manually craft HTTP requests to www.googleapis.com/calendar/v3/.... This invites token expiration crashes and parsing errors.

The Architect Standard: Use the official Google API Client Libraries for Android.

1. Add dependencies in build.gradle.kts:

   implementation("com.google.api-client:google-api-client-android:1.33.0")
   implementation("com.google.apis:google-api-services-calendar:v3-rev411-1.25.0")
   

2. Construct the Calendar Client securely:

   val credential = GoogleAccountCredential.usingOAuth2(context, listOf(CalendarScopes.CALENDAR_EVENTS))
   credential.selectedAccount = account.account // from CredentialManager
   
   val service = Calendar.Builder(
       com.google.api.client.extensions.android.http.AndroidHttp.newCompatibleTransport(),
       com.google.api.client.json.gson.GsonFactory.getDefaultInstance(),
       credential
   ).setApplicationName("TodoApp").build()
   

🔄 Rule 3: Background Sync via WorkManager

Never sync to Google Calendar on the main thread or directly from the UI layer. Ensure event-creation happens in the background.

class CalendarSyncWorker(context: Context, params: WorkerParameters) : CoroutineWorker(context, params) {
    override suspend fun doWork(): Result = withContext(Dispatchers.IO) {
        val todoId = inputData.getString("TODO_ID") ?: return@withContext Result.failure()
        
        try {
            val event = Event().apply {
                summary = "Complete Todo: $todoId"
                start = EventDateTime().setDateTime(DateTime(System.currentTimeMillis()))
                end = EventDateTime().setDateTime(DateTime(System.currentTimeMillis() + 3600000))
            }
            
            // service is injected
            service.events().insert("primary", event).execute()
            Result.success()
        } catch (e: Exception) {
            Result.retry() // WorkManager will automatically retry on network failure!
        }
    }
}

🛑 Common Hallucinations to Avoid

1. API Keys: Google Workspace APIs (Calendar/Drive) require OAuth 2.0 Client IDs, NOT restricted API Keys.
2. Intent Fallback: If a user is not signed in to a Google Account, you cannot blindly fire the Calendar Client. You must intercept the UserRecoverableAuthIOException to re-prompt the user to sign in.