I want to to backup data in Backups on user Google Drive account and restore them.
I have seen apps, like WhatsApp that allow users to login through google drive and do periodic backup to the user cloud.
I don't want to use firebase cloud since the data is access by the user himself and not other users and it will be costly if the data is large. Is there any available package can do this? Or tutorial otherwise how to achieve this in flutter?
Step 1
You need to have already created a Google Firebase Project, and enable Google Drive API from Google Developer Console. Note that you need to select the same project in Google Developer Console as you have created in Google Firebase.
Step 2
you need to log in with google to get googleSignInAccount and use dependencies
googleapis: ^0.54.0
googleapis_auth: ^0.2.11
class GoogleHttpClient extends IOClient {
Map<String, String> _headers;
GoogleHttpClient(this._headers) : super();
@override
Future<http.StreamedResponse> send(http.BaseRequest request) =>
super.send(request..headers.addAll(_headers));
@override
Future<http.Response> head(Object url, {Map<String, String> headers}) =>
super.head(url, headers: headers..addAll(_headers));
}
Upload File to Google Drive
_uploadFileToGoogleDrive() async {
var client = GoogleHttpClient(await googleSignInAccount.authHeaders);
var drive = ga.DriveApi(client);
ga.File fileToUpload = ga.File();
var file = await FilePicker.getFile();
fileToUpload.parents = ["appDataFolder"];
fileToUpload.name = path.basename(file.absolute.path);
var response = await drive.files.create(
fileToUpload,
uploadMedia: ga.Media(file.openRead(), file.lengthSync()),
);
print(response);
}
Download Google Drive File
Future<void> _downloadGoogleDriveFile(String fName, String gdID) async {
var client = GoogleHttpClient(await googleSignInAccount.authHeaders);
var drive = ga.DriveApi(client);
ga.Media file = await drive.files
.get(gdID, downloadOptions: ga.DownloadOptions.FullMedia);
print(file.stream);
final directory = await getExternalStorageDirectory();
print(directory.path);
final saveFile = File('${directory.path}/${new DateTime.now().millisecondsSinceEpoch}$fName');
List<int> dataStore = [];
file.stream.listen((data) {
print("DataReceived: ${data.length}");
dataStore.insertAll(dataStore.length, data);
}, onDone: () {
print("Task Done");
saveFile.writeAsBytes(dataStore);
print("File saved at ${saveFile.path}");
}, onError: (error) {
print("Some Error");
});
}
Its easy but you have to go through a series of Steps to complete it.
1. Enable Google Drive API
click on the link to google console : https://console.developers.google.com/apis/library?project=diary-app-339509
form to fill to make OAuth client id
2. Make project available for external use .
for testing add test user email address
Now comes the coding part on flutter
3. Add the following packages to pubspec.yaml
googleapis: ^7.0.0
googleapis_auth: ^1.3.0
flutter_secure_storage: ^5.0.2
url_launcher: ^6.0.0-nullsafety
4. Get authentication from google and store the Auth details for future auths
Use the following class for storing Auth Details
import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:googleapis_auth/auth_io.dart';
class SecureStorage {
final storage = FlutterSecureStorage();
//Save Credentials
Future saveCredentials(AccessToken token, String refreshToken) async {
print(token.expiry.toIso8601String());
await storage.write(key: "type", value: token.type);
await storage.write(key: "data", value: token.data);
await storage.write(key: "expiry", value: token.expiry.toString());
await storage.write(key: "refreshToken", value: refreshToken);
}
//Get Saved Credentials
Future<Map<String, dynamic>?> getCredentials() async {
var result = await storage.readAll();
if (result.isEmpty) return null;
return result;
}
//Clear Saved Credentials
Future clear() {
return storage.deleteAll();
}
}
5.Finally use this class for saving your file to Drive
import 'dart:io';
import 'package:googleapis/drive/v3.dart' as ga;
import 'package:googleapis_auth/auth_io.dart';
import 'package:http/http.dart' as http;
import 'package:path/path.dart' as p;
import 'package:path_provider/path_provider.dart';
import 'package:personal_diary/app/utils/secure_storage.dart';
import 'package:url_launcher/url_launcher.dart';
const _clientId = "379503391554-6d33j9e6lan7lg0ac7sj81026u8nigs8.apps.googleusercontent.com";
const _scopes = ['https://www.googleapis.com/auth/drive.file'];
class GoogleDrive {
final storage = SecureStorage();
//Get Authenticated Http Client
Future<http.Client> getHttpClient() async {
//Get Credentials
var credentials = await storage.getCredentials();
if (credentials == null) {
//Needs user authentication
var authClient = await clientViaUserConsent(
ClientId(_clientId),_scopes, (url) {
//Open Url in Browser
launch(url);
});
//Save Credentials
await storage.saveCredentials(authClient.credentials.accessToken,
authClient.credentials.refreshToken!);
return authClient;
} else {
print(credentials["expiry"]);
//Already authenticated
return authenticatedClient(
http.Client(),
AccessCredentials(
AccessToken(credentials["type"], credentials["data"],
DateTime.tryParse(credentials["expiry"])!),
credentials["refreshToken"],
_scopes));
}
}
// check if the directory forlder is already available in drive , if available return its id
// if not available create a folder in drive and return id
// if not able to create id then it means user authetication has failed
Future<String?> _getFolderId(ga.DriveApi driveApi) async {
final mimeType = "application/vnd.google-apps.folder";
String folderName = "personalDiaryBackup";
try {
final found = await driveApi.files.list(
q: "mimeType = '$mimeType' and name = '$folderName'",
$fields: "files(id, name)",
);
final files = found.files;
if (files == null) {
print("Sign-in first Error");
return null;
}
// The folder already exists
if (files.isNotEmpty) {
return files.first.id;
}
// Create a folder
ga.File folder = ga.File();
folder.name = folderName;
folder.mimeType = mimeType;
final folderCreation = await driveApi.files.create(folder);
print("Folder ID: ${folderCreation.id}");
return folderCreation.id;
} catch (e) {
print(e);
return null;
}
}
uploadFileToGoogleDrive(File file) async {
var client = await getHttpClient();
var drive = ga.DriveApi(client);
String? folderId = await _getFolderId(drive);
if(folderId == null){
print("Sign-in first Error");
}else {
ga.File fileToUpload = ga.File();
fileToUpload.parents = [folderId];
fileToUpload.name = p.basename(file.absolute.path);
var response = await drive.files.create(
fileToUpload,
uploadMedia: ga.Media(file.openRead(), file.lengthSync()),
);
print(response);
}
}
Future<void> _downloadGoogleDriveFile(String fName, String gdID) async {
var client = await getHttpClient();
var drive = ga.DriveApi(client);
ga.Media file = await drive.files.get(gdID, downloadOptions: ga.DownloadOptions.FullMedia);
print(file.stream);
final directory = await getExternalStorageDirectory();
print(directory);
final saveFile = File('$directory/${DateTime.now().millisecondsSinceEpoch}$fName');
List<int> dataStore = [];
file.stream.listen((data) {
print("DataReceived: ${data.length}");
dataStore.insertAll(dataStore.length, data);
}, onDone: () {
print("Task Done");
saveFile.writeAsBytes(dataStore);
print("File saved at ${saveFile.path}");
}, onError: (error) {
print("Some Error");
});
}
}