Google Drive Integration with Firebase

This guide explains how to integrate Google Sign-In with Firebase and use Google Drive API to upload data in a Jetpack Compose application.

Prerequisites

1. Firebase Project: Create a Firebase project in the Firebase Console.
2. Google API Console: Set up Google Drive API in the Google API Console.
3. Android Studio: Ensure you have Android Studio installed.

Step 1: Configure Firebase and Google Sign-In

1.1. Set up Firebase in your project

1. Go to the Firebase Console.
2. Select your project and click on "Add app" to add an Android app.
3. Follow the instructions to download the google-services.json file.
4. Place the google-services.json file in the app directory of your Android project.

1.2. Add Firebase SDK to your project

Add the following dependencies to your build.gradle files.

Project-level build.gradle (usually in the root directory):**

plugins {
    /....
    id("com.google.gms.google-services") version "4.4.2" apply false
}

App-level build.gradle (usually in the app directory):

plugins {
    alias(libs.plugins.android.application)
    alias(libs.plugins.jetbrains.kotlin.android)
    id("com.google.gms.google-services") // this line
}

dependencies {
    implementation("com.google.firebase:firebase-bom:33.2.0")
    implementation("com.google.firebase:firebase-auth")
    implementation("com.google.android.gms:play-services-auth:21.2.0")

    implementation ("com.google.api-client:google-api-client-android:1.33.2")
    implementation ("com.google.api-client:google-api-client-gson:1.33.2")
    implementation ("com.google.apis:google-api-services-drive:v3-rev197-1.25.0")
}

1.3. Set up Google-Signin

1. In the Firebase Console, go to the Authentication section.
2. Enable the Google sign-in method.

Step 2: Implement google sign in

2.1. Create a GoogleSignInClient

val googleSignInOptions =
            GoogleSignInOptions
                .Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken("Your web client here")
                .requestEmail()
                .requestScopes(Scope(Scopes.DRIVE_FILE))
                .build()
        val googleSignInClient = GoogleSignIn.getClient(this, googleSignInOptions)
        signInLauncher.launch(googleSignInClient.signInIntent)
}

2.2. Create a launcher to launch signin intent

signInLauncher =
            registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
                handleSignInResult(result, this)
            }

Step 3: Integrate Google Drive and upload data

3.1. Handle Sign in result

private fun handleSignInResult(
    result: ActivityResult,
    context: Context,
) {
    val data = result.data
    val task = GoogleSignIn.getSignedInAccountFromIntent(data)
    try {
        val account = task.getResult(ApiException::class.java)
        if (account != null) {
            Log.d("GoogleSignIn", "Account: ${account.email}")
            firebaseAuthWithGoogle(account.idToken!!, context)
        } else {
            Log.w("GoogleSignIn", "Account is null")
        }
    } catch (e: ApiException) {
        Log.w("GoogleSignIn", "Google sign-in failed", e)
    }
}

3.2. Authenticate with Firebase Using Google

private fun firebaseAuthWithGoogle(
    idToken: String,
    activity: MainActivity,
) {
    val credential = GoogleAuthProvider.getCredential(idToken, null)
    FirebaseAuth.getInstance().signInWithCredential(credential)
        .addOnCompleteListener(activity) { task ->
            if (task.isSuccessful) {
                val account = GoogleSignIn.getLastSignedInAccount(activity)
                account?.let {
                    // Proceed to Google Drive API operations
                    initGoogleDriveService(it, activity)
                }
            } else {
                Log.w("GoogleSignIn", "signInWithCredential:failure", task.exception)
            }
        }
}

3.3. Initialize Google Drive API Service

private fun initGoogleDriveService(account: GoogleSignInAccount, activity: MainActivity) {
    CoroutineScope(Dispatchers.IO).launch {
        try {
            val googleAccountCredential = GoogleAccountCredential.usingOAuth2(
                activity, listOf(Scopes.DRIVE_FILE)
            )
            googleAccountCredential.selectedAccount = account.account

            val driveService = Drive.Builder(
                NetHttpTransport(), GsonFactory(), googleAccountCredential
            ).setApplicationName("Your Project Name").build()

            // Call the method to create folder in Google Drive
            createFolderInGoogleDrive(driveService, activity)

            withContext(Dispatchers.Main) {
                Log.d("GoogleDrive", "Drive service initialized successfully")
            }
        } catch (e: Exception) {
            withContext(Dispatchers.Main) {
                Log.e("GoogleDrive", "Error initializing Drive service: ${e.message}")
            }
        }
    }
}

3.4. Create Folder in Google Drive

private fun createFolderInGoogleDrive(
    driveService: Drive,
    context: MainActivity,
) {
    val metadata = File().apply {
        name = "Backup Folder"
        mimeType = "application/vnd.google-apps.folder"
    }

    val folder = driveService.files().create(metadata).setFields("id").execute()

    Log.d("GoogleDrive", "Folder ID: ${folder.id}")

    // Call upload method after folder is created
    uploadFileToGoogleDrive(
        driveService,
        folder.id,
        "photo.jpg", // Replace with the desired file name
        Uri.parse("android.resource://YourApplicationPackage/drawable/yourfilename"),
        context,
    )
}

3.5. Upload File to Google Drive

private fun uploadFileToGoogleDrive(
    driveService: Drive,
    folderId: String,
    fileName: String,
    fileUri: Uri,
    context: Context,
) {
    val fileMetadata = File().apply {
        name = fileName
        parents = listOf(folderId) // Place the file in the specific folder
        mimeType = "image/jpg" // Use appropriate MIME type based on your file
    }

    val inputStream = context.contentResolver.openInputStream(fileUri)
    val fileContent = InputStreamContent("image/jpg", inputStream)

    val file = driveService.files().create(fileMetadata, fileContent)
        .setFields("id")
        .execute()

    Log.d("GoogleDrive", "File uploaded with ID: ${file.id}")
}

Step 4: Enable Google Drive API

Don't forget to enable the Google Drive API in the Google API Console.