Calculation/app/lib/nls_token.js

'use strict';

/**
 * 阿里云获取语音token接口
 *
 * @author CaiAoLin
 * @date 2018/1/25
 * @version
 */

const Core = require('@alicloud/pop-core');
const smsAli = require('../const/sms_alitemplate.js');
const Nls = require('alibabacloud-nls');
class NlsToken {
    constructor(ctx) {
        this.ctx = ctx;
        this.appkey = 'nE0d2Ue08rtPhb9e';
        this.shotUrl = 'wss://nls-gateway.cn-shanghai.aliyuncs.com/ws/v1';
    }

    async getToken() {
        const client = new Core({
            accessKeyId: smsAli.accessKey,
            accessKeySecret: smsAli.accessKeySecret,
            endpoint: 'https://nls-meta.cn-shanghai.aliyuncs.com', // 注意语音服务用这个endpoint
            apiVersion: '2019-02-28',
        });

        const params = {
            Action: 'CreateToken',
        };

        const requestOption = {
            method: 'POST',
        };

        try {
            const result = await client.request('CreateToken', params, requestOption);
            return result.Token.Id;
        } catch (err) {
            this.ctx.logger.error('获取语音识别Token失败', err);
            throw err;
        }
    }

    /**
     * audioBuffer: Buffer of wav (16k)
     */
    async oneShotRecognition(token, audioBuffer, url = this.shotUrl, appkey = this.appkey) {
        return new Promise(async (resolve, reject) => {
            let finalText = '';

            const sr = new Nls.SpeechRecognition({
                url,
                appkey,
                token,
                enable_punctuation_prediction: false,
                enable_inverse_text_normalization: true,
            });

            sr.on('started', (msg) => {
                try {
                    const data = JSON.parse(msg);
                    // console.log('Client recv started:', data);
                } catch (err) {
                    console.log('started parse error:', err);
                }
            });

            sr.on('changed', (msg) => {
                try {
                    const data = JSON.parse(msg);
                    if (data.payload && data.payload.result) {
                        finalText = data.payload.result;
                    }
                    console.log('changed finalText:', finalText);
                } catch (err) {
                    console.log('changed parse error:', err);
                }
            });

            sr.on('completed', (msg) => {
                try {
                    const data = JSON.parse(msg);
                    if (data.payload && data.payload.result) {
                        finalText = data.payload.result;
                    }
                    // console.log('completed finalText:', finalText);
                } catch (err) {
                    console.log('completed parse error:', err);
                }
            });

            sr.on('closed', () => {
                // console.log('closed finalText:', finalText);
                resolve(finalText.trim());
            });

            sr.on('failed', (msg) => {
                try {
                    const data = JSON.parse(msg);
                    reject(new Error(JSON.stringify(data)));
                } catch (err) {
                    reject(new Error(msg));
                }
            });

            try {
                // 启动识别
                await sr.start(sr.defaultStartParams(), true, 6000);

                if (!sr.sendAudio(audioBuffer)) {
                    throw new Error('send audio failed');
                }
                await sr.close();
            } catch (err) {
                console.log('error on start:', err);
                return reject(err);
            }
        });
    }
}

module.exports = NlsToken;