Speech Adaptation in Dialogflow

index.js

const uuid = require('uuid');
const df = require('dialogflow').v2beta1;

const sessionId = uuid.v4();
const sessionClient = new df.SessionsClient();
const sessionPath = sessionClient.sessionPath(projectId, sessionId);

let request = {
  session: sessionPath,
  queryInput: {
    audioConfig: {
      sampleRateHertz: 16000,
      encoding: 'AUDIO_ENCODING_LINEAR_16',
      languageCode: 'en-US',
      speechContexts: [
          {
            phrases: [
              'mail',
              'email'
            ],
            boost: 20.0
          }
      ]
    },
    singleUtterance: singleUtterance
  }
}

request.inputAudio = audio;
const responses = await sessionClient.detectIntent(request);