我想在用户 Google Drive 帐户的 Backups 中备份数据并恢复它们。
我见过像 WhatsApp 这样的应用程序，它们允许用户通过 google drive 登录并定期备份到用户云。
我不想使用 firebase 云，因为数据是由用户自己而不是其他用户访问的，如果数据很大，成本会很高。有没有可用的软件包可以做到这一点？或者教程如何在颤振中实现这一点？
【问题讨论】：
标签： flutter google-drive-api backup
第 1 步
您需要已经创建了一个 Google Firebase 项目，并从 Google Developer Console 中启用 Google Drive API。请注意，您需要在 Google Developer Console 中选择与在 Google Firebase 中创建的项目相同的项目。
第 2 步
您需要使用 google 登录才能获取 googleSignInAccount 并使用 依赖关系
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));
}
将文件上传到 Google 云端硬盘
_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);
}
下载 Google 云端硬盘文件
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");
});
}
【讨论】：
这很容易，但您必须经过一系列步骤才能完成。
1.启用 Google Drive API
点击链接到谷歌控制台： https://console.developers.google.com/apis/library?project=diary-app-339509
form to fill to make OAuth client id
2。使项目可供外部使用。
for testing add test user email address
接下来是 Flutter 的编码部分
3.将以下包添加到 pubspec.yaml
googleapis: ^7.0.0
googleapis_auth: ^1.3.0
flutter_secure_storage: ^5.0.2
url_launcher: ^6.0.0-nullsafety
4.从 google 获取身份验证并存储身份验证详细信息以供将来身份验证使用
使用以下类来存储 Auth 详细信息
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.最后使用此类将文件保存到云端硬盘
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");
});
}
}
【讨论】：