谷歌语音api，node.js客户端 - 使用'操作'时出错

Question

我正在使用node.js客户端库，特别是startRecognition方法，并获得我使用speech.operation的结果。但是，我得到以下结果而不是结果 - 查看包含一些编码字符串而不是JavaScript对象的“value”对象。

{ result: 'response',
  name: '3939860839213416358',
  metadata: 
   { typeUrl: 'type.googleapis.com/google.cloud.speech.v1.LongRunningRecognizeMetadata',
     value: 'CGQSCwiKx47IBRCg6pRuGgsIqM6OyAUQgO+vYQ==' },
  done: true,
  error: null,
  response: 
   { typeUrl: 'type.googleapis.com/google.cloud.speech.v1.LongRunningRecognizeResponse',
     value: 'EoQaCtICCsoCVGhleSBzbWFsbCBsYXRlc3QgZW52aXJvbm1lbnQuIFdlIGhhdmUgYSBjb3Jwb3JhdGUgYnVzaW5lc3Mgc2VydmljZSBhbmQgdGhlcmVmb3Jl' } }

有人见过这个吗？这是一个错误吗？或者有没有办法将其解码为JavaScript对象？

以下是演示此问题的代码段：

var Speech = require('@google-cloud/speech')({
  projectId: 'my project name',
  keyFilename: '<key file name>.json'
});

var opName='';

var config = {
  encoding: 'LINEAR16',
  sampleRateHertz: 48000,
  languageCode: 'en-US',
  maxAlternatives: 10
};

asyncGoogleASR('gs://file-location',config);

function asyncGoogleASR(googleCloudURI,request) {
    Speech.startRecognition(googleCloudURI, request,async_callback);
}
function async_callback(err, operation, apiResponse) {
  if (err) {
    console.log(err);
  }
  opName=operation.latestResponse.name;

   operation
    .on('error', function(err) {
        console.log("error");
        console.log(err);
    })
    .on('complete', function(results) {
        console.log(results);  // this works okay
        var op = Speech.operation(opName);
           op
            .on('error', function(err) {
                console.log("error");
                console.log(err);
            })
            .on('complete', function(results) {
                console.log(results);  // this prints garbage
            });
   });


 }