TinyMan/node-jeanne

const google_speech = require('google-speech')
const path = require('path')
const ffmpeg = require("fluent-ffmpeg")
const Stream = require("stream")
const fs = require('fs')
const keys = require('keys/api-keys.json')
const google_api_key = keys["google-speech"]
const logger = require('lib/logger')('SpeechStream')


function SpeechStream(engine = "GOOGLE", lang = "fr-FR") {
    return new GoogleStream(google_api_key, lang)
}


class GoogleStream extends Stream.Writable {
    constructor(api_key, lang) {
        super()
        this.api_key = api_key
        this.lang = lang
        this.textStream = new Stream.PassThrough({
            objectMode: true
        })
        this.acc = []
        this.timeout = null
        this.pending = false
        this.input = this.converted = null
    }
    _write(chunk, encoding, cb) {
        clearTimeout(this.timeout)
        if (this.pending) {
            this.acc.push(chunk)
        } else {
            if (this.input == null) {
                this.input = new Stream.PassThrough
                this.converted = new Stream.PassThrough
                ffmpeg(this.input)
                    .withInputFormat('s16le')
                    .format('s16le')
                    .withAudioFrequency(16000)
                    .pipe(this.converted)

                if (this.acc.length > 0) {
                    this.input.write(Buffer.concat(this.acc))
                    this.acc = []
                }
            }
            this.input.write(chunk)
            this.timeout = setTimeout(this.makeRequest.bind(this), 500)
        }
        cb()
    }
    makeRequest() {
        logger.log("Making request ..\n")
        this.pending = true
        this.input.end()
        google_speech.ASR({
            //debug: true,
            developer_key: this.api_key,
            stream: this.converted,
            lang: this.lang
        }, this.requestCallback.bind(this))
    }
    requestCallback(err, res) {
        this.converted = null
        this.input = null
        this.pending = false
        if (err) return logger.error(err)
        this.handleResponse(res)
    }
    handleResponse(response) {
        logger.log(JSON.stringify(response))
        if (response.result && response.result.length > 0)
            this.textStream.push(response.result[response.result_index].alternative)
    }
}

module.exports = SpeechStream