使用 Android java 应用程序中的服务帐户连接到 google Drive API v3

Question

我正在开发一个 Android 应用程序，供我工作的公司内部使用。我需要将文本文件保存在 Google 云端硬盘的共享云端硬盘上。 在我开发的 Web 应用程序中使用服务帐户之前，我已经这样做过几次，但我似乎无法在 Android 应用程序环境中正确设置连接。

我已经尝试过谷歌提供的示例https://developers.google.com/drive/api/v3/quickstart/java但似乎这与Android不兼容，因为它尝试使用库仅在桌面环境中可用。

这是我实现的代码：

// Implements OnClick for sendData button
public void onClickSendData(View view) {
    try {
        // Build a new authorized API client service.
        final NetHttpTransport HTTP_TRANSPORT = new com.google.api.client.http.javanet.NetHttpTransport();
        Drive service = new Drive.Builder(HTTP_TRANSPORT, JSON_FACTORY, getCredentials(HTTP_TRANSPORT))
                .setApplicationName(APPLICATION_NAME)
                .build();

        // Upload file to google drive
        String timeStamp = new SimpleDateFormat("yyyyMMddHHmmss", Locale.forLanguageTag("hu-HU")).format(new java.util.Date());
        File fileMetadata = new File();
        fileMetadata.setName("scan_" + timeStamp + ".txt");
        fileMetadata.setParents(new ArrayList<String>(Arrays.asList(TARGET_FOLDER_ID)));
        java.io.File filePath = new java.io.File(getFilesDir() + java.io.File.separator + BARCODE_CONTAINER_TEMP_FILE);
        FileContent mediaContent = new FileContent("text/plain", filePath);
        File file = service.files().create(fileMetadata, mediaContent)
                .setFields("id")
                .execute();

        barcodeContainer.setText(R.string.tarhely_ures);
        barcodContainerEmptyFlag = true;

    }
    catch(Exception ex) {
        // Handle any exception
        ex.printStackTrace();

    }

}

private Credential getCredentials(final NetHttpTransport HTTP_TRANSPORT) throws IOException {
    // Load client secrets.
    InputStream in = MainActivity.class.getResourceAsStream(CREDENTIALS_FILE_PATH);
    if (in == null)
        throw new FileNotFoundException("Resource not found: " + CREDENTIALS_FILE_PATH);

    GoogleClientSecrets clientSecrets = GoogleClientSecrets.load(JSON_FACTORY, new InputStreamReader(in));

    java.io.File tokenFile = new java.io.File(getFilesDir() + java.io.File.separator + TOKENS_DIRECTORY_PATH);
    if(!tokenFile.isDirectory())
        tokenFile.mkdirs();

    // Build flow and trigger user authorization request.
    GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow.Builder(
            HTTP_TRANSPORT, JSON_FACTORY, clientSecrets, SCOPES)
            .setDataStoreFactory(new FileDataStoreFactory(tokenFile))
            .setAccessType("offline")
            .build();
    LocalServerReceiver receiver = new LocalServerReceiver.Builder().setPort(8888).build();

    return new AuthorizationCodeInstalledApp(flow, receiver).authorize("user");

}

运行时错误如下：

java.lang.ClassNotFoundException: Didn't find class “java.awt.Desktop” in Android

Answer 1

我终于找到了问题的答案，这是我使用

GoogleCredential.Builder()

记录的解决方案这里：

    //  Upload file to google drive
    public void uploadBarcodeFileToDrive() throws IOException, GeneralSecurityException {
        // Get service account secret
        InputStream inputStream = MainActivity.class.getResourceAsStream(CREDENTIALS_FILE_PATH);
        if (inputStream == null)
            throw new FileNotFoundException("Resource not found: " + CREDENTIALS_FILE_PATH);

        // Convert inputStream to file
        java.io.File clientSecret = new java.io.File(getFilesDir() + java.io.File.separator + "credentials.p12");
        OutputStream outputStream = new FileOutputStream(clientSecret);
        IOUtils.copy(inputStream, outputStream);
        if (!clientSecret.exists())
            throw new FileNotFoundException("Credentials (credentials.p12) not created from: " + CREDENTIALS_FILE_PATH);

        // Http transport creation
        HttpTransport httpTransport = AndroidHttp.newCompatibleTransport();
        // Instance of the JSON factory
        JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
        // Instance of the scopes required
        List<String> scopes = new ArrayList<>();
        scopes.add(DriveScopes.DRIVE);
        // Build Google credential
        GoogleCredential credential = new GoogleCredential.Builder()
                .setTransport(httpTransport)
                .setJsonFactory(jsonFactory)
                .setServiceAccountId(SERVICE_ACCOUNT_PROVIDER)
                .setServiceAccountScopes(scopes)
                .setServiceAccountPrivateKeyFromP12File(clientSecret)
                .setServiceAccountUser(SERVICE_ACCOUNT_USER)
                .build();
        // Build Drive service
        Drive service = new Drive.Builder(httpTransport, jsonFactory, credential)
                .setApplicationName(APPLICATION_NAME)
                .build();

        // Parents
        List<String> parents = new ArrayList<>();
        parents.add(TARGET_FOLDER_ID);
        // Setup file
        String timeStamp = new SimpleDateFormat("yyyyMMddHHmmss", Locale.forLanguageTag("hu-HU")).format(new java.util.Date());
        File fileMetadata = new File();
        fileMetadata.setName("scan_" + timeStamp + ".txt");
        fileMetadata.setParents(parents);
        java.io.File filePath = new java.io.File(getFilesDir() + java.io.File.separator + BARCODE_CONTAINER_TEMP_FILE);
        FileContent mediaContent = new FileContent("text/plain", filePath);
        // Upload file to google drive
        service.files().create(fileMetadata, mediaContent)
                .setFields("id")
                .execute();

    }

问题中描述的示例的主要区别，以及当前的解决方案如下：

• 对于

  GoogleCredential.Builder()

  ，我需要在 dev.console 中为现有服务帐户创建一个

  .p12

  类型密钥。
• 密钥存储在项目的 asset/credentials 文件夹中。
• 这个新密钥需要设置为

  java.io.File

  而不是

  InputStream

  ，因此我从项目资产中读取它，并在调用方法时将其复制到内部存储。

• SERVICE_ACCOUNT_USER

  应是服务帐户的

  [..]@[..].iam.gserviceaccount.com

  样式电子邮件地址。
• 如果您想使用“真实”帐户作为上传者，例如您想上传到用户的驱动器或与特定用户共享的文件夹，则

  setServiceAccountUser(SERVICE_ACCOUNT_USER)

  是必需的。
• 此用户应具有 dev.console 中服务帐户的访问权限。