nodejs_google_tts_api_example.ts

// Imports the Google Cloud client library
import { TextToSpeechClient } from '@google-cloud/text-to-speech';
import fs from 'fs-extra';
import { promisify } from 'util';
// Creates a client
const client = new TextToSpeechClient();
const convertSSMLtoAudio = async (ssmlText: any, langCode: string, gender: string) =>
  // eslint-disable-next-line no-async-promise-executor
  new Promise(async (resolve, reject) => {
    try {
      const audioFileName = `${Date.now().toString()}.mp3`;
      // Constructs the request
      const request: any = {
        // Select the text to synthesize
        input: { ssml: `<speak>${ssmlText}</speak>` },
        // Select the language and SSML Voice Gender (optional)
        voice: { languageCode: langCode ?? 'en-US', name: 'en-US-Wavenet-C', ssmlGender: gender ?? 'NEUTRAL' },
        // Select the type of audio encoding
        audioConfig: { audioEncoding: 'MP3', speakingRate: 1.1 },
      };

      // Performs the text-to-speech request
      const [response] = await client.synthesizeSpeech(request);
      // Write the binary audio content to a local file
      const writeFile = promisify(fs.writeFile);
      await writeFile(`assets/audio/${audioFileName}`, response.audioContent, 'binary');
      // await writeFile(path.join(__dirname, '../../../', 'assets/audio', audioFileName), response.audioContent, 'binary');
      // console.log('Audio content written to file: output.mp3');
      resolve(audioFileName);
    } catch (err) {
      reject(err);
    }
  });

const convertTextToAudio = async (text: string, langCode: string, gender: string) =>
  // eslint-disable-next-line no-async-promise-executor
  new Promise(async (resolve, reject) => {
    try {
      const audioFileName = `${Date.now().toString()}.mp3`;
      // Constructs the request
      const request: any = {
        // Select the text to synthesize
        input: { text: text },
        // Select the language and SSML Voice Gender (optional)
        voice: { languageCode: langCode ?? 'en-US', ssmlGender: gender ?? 'NEUTRAL' },
        // Select the type of audio encoding
        audioConfig: { audioEncoding: 'MP3', speakingRate: 1.1 },
      };

      // Performs the text-to-speech request
      const [response] = await client.synthesizeSpeech(request);
      // Write the binary audio content to a local file
      const writeFile = promisify(fs.writeFile);
      await writeFile(`assets/audio/${audioFileName}`, response.audioContent, 'binary');
      // await writeFile(path.join(__dirname, '../../../', 'assets/audio', audioFileName), response.audioContent, 'binary');
      // console.log('Audio content written to file: output.mp3');
      resolve(audioFileName);
    } catch (err) {
      reject(err);
    }
  });

/**
 * @description Function to delete file from public directory.
 * @param fileName fileName to be deleted from server to remove from conversation cache
 */
const removeAudioFile = async (fileName: string) => {
  fs.unlink(`public/${fileName}`, (err) => {
    if (err) {
      console.log('DELETING FILE ERROR : ', err);
    }
  });
};

const TextToSpeech = { convertSSMLtoAudio, convertTextToAudio, removeAudioFile };
export { TextToSpeech };