错误：OAuth2Credentials 实例不支持刷新访问令牌。如何使用令牌值字符串创建 AccessToken 实例？

Question

我正在使用 Android 上的 Google Speech to Text 服务将语音流式传输到文本。 Here is official sample repository. 样本运行成功。但是或者，您应该在服务器端获取访问令牌，并提供给客户端应用程序。

所以我设置了一个服务器并为应用程序创建 RESTful api 以获取访问令牌。 {"token":"1234567890sdertyuikjhgfghjk....."}

并且还使用 api:https://www.googleapis.com/oauth2/v1/tokeninfo?access_token={token} 来获取令牌信息：

{
 "issued_to": "102073270616313859663",
 "audience": "102073270616313859663",
 "scope": "https://www.googleapis.com/auth/cloud-platform",
 "expires_in": 3600,
 "access_type": "offline"
}

然后创建一个 AccessToken 实例： AccessToken token = new AccessToken(tokenValue, expiresIn);

但出现以下错误：

07-04 20:14:07.395 3023-3067/com.google.cloud.android.speech E/SpeechService: Error calling the API.
io.grpc.StatusRuntimeException: UNKNOWN
    at io.grpc.Status.asRuntimeException(Status.java:543)
    at io.grpc.stub.ClientCalls$StreamObserverToCallListenerAdapter.onClose(ClientCalls.java:395)
    at io.grpc.ClientInterceptors$CheckedForwardingClientCall.start(ClientInterceptors.java:202)
    at io.grpc.stub.ClientCalls.startCall(ClientCalls.java:276)
    at io.grpc.stub.ClientCalls.asyncStreamingRequestCall(ClientCalls.java:266)
    at io.grpc.stub.ClientCalls.asyncBidiStreamingCall(ClientCalls.java:106)
    at com.google.cloud.speech.v1.SpeechGrpc$SpeechStub.streamingRecognize(SpeechGrpc.java:217)
    at com.google.cloud.android.speech.SpeechService.startRecognizing(SpeechService.java:264)
    at com.google.cloud.android.speech.MainActivity$1.onVoiceStart(MainActivity.java:62)
    at com.google.cloud.android.speech.VoiceRecorder$ProcessVoice.run(VoiceRecorder.java:199)
    at java.lang.Thread.run(Thread.java:764)
 Caused by: java.lang.IllegalStateException: OAuth2Credentials instance does not support refreshing the access token. An instance with a new access token should be used, or a derived type that supports refreshing.
    at com.google.auth.oauth2.OAuth2Credentials.refreshAccessToken(OAuth2Credentials.java:208)
    at com.google.auth.oauth2.OAuth2Credentials.refresh(OAuth2Credentials.java:175)
    at com.google.auth.oauth2.OAuth2Credentials.getRequestMetadata(OAuth2Credentials.java:161)
    at com.google.cloud.android.speech.SpeechService$GoogleCredentialsInterceptor.getRequestMetadata(SpeechService.java:532)
    at com.google.cloud.android.speech.SpeechService$GoogleCredentialsInterceptor.access$900(SpeechService.java:450)
    at com.google.cloud.android.speech.SpeechService$GoogleCredentialsInterceptor$1.checkedStart(SpeechService.java:474)
    at io.grpc.ClientInterceptors$CheckedForwardingClientCall.start(ClientInterceptors.java:194)
    at io.grpc.stub.ClientCalls.startCall(ClientCalls.java:276) 
    at io.grpc.stub.ClientCalls.asyncStreamingRequestCall(ClientCalls.java:266) 
    at io.grpc.stub.ClientCalls.asyncBidiStreamingCall(ClientCalls.java:106) 
    at com.google.cloud.speech.v1.SpeechGrpc$SpeechStub.streamingRecognize(SpeechGrpc.java:217) 
    at com.google.cloud.android.speech.SpeechService.startRecognizing(SpeechService.java:264) 
    at com.google.cloud.android.speech.MainActivity$1.onVoiceStart(MainActivity.java:62) 
    at com.google.cloud.android.speech.VoiceRecorder$ProcessVoice.run(VoiceRecorder.java:199) 
    at java.lang.Thread.run(Thread.java:764) 

我可以使用示例代码：

 final InputStream stream = getResources().openRawResource(R.raw.credential);
 final GoogleCredentials credentials = 
 GoogleCredentials.fromStream(stream).createScoped(SCOPE);
 final AccessToken token = credentials.refreshAccessToken();

得到一个working Token，通过getTokenValue()得到它的token值，通过getExpirationTime得到它的过期时间。然后创建一个 Token 实例： AccessToken token = new AccessToken(tokenValue, expiresIn); 返回一个 AccessToken 实例。但它会导致同样的错误。

所以我的问题是，当我获得令牌值字符串和到期时间时，如何创建一个 工作 AccessToken 实例。

Answer 1

不幸的是，我仍然无法通过构造函数创建一个有效的AccessToken。但我使用套接字服务器来解决问题。因为AccessToken已经实现了Serializable接口。因此，客户端和服务器之间的通信要容易得多。

服务器

private void  runServer() throws IOException, ClassNotFoundException{
    ServerSocket ss = new ServerSocket(port);

    Socket socket = ss.accept();
    ObjectOutputStream os = new ObjectOutputStream(socket.getOutputStream());
    ObjectInputStream is = new ObjectInputStream(socket.getInputStream());

    final InputStream stream = new ByteArrayInputStream(credential.getBytes(StandardCharsets.UTF_8));
    final GoogleCredentials credentials = GoogleCredentials.fromStream(stream)
                    .createScoped(SCOPE);
    final AccessToken token = credentials.refreshAccessToken();
    os.writeObject(token);
}