index.js

const exec = require('child_process').execSync;
const express = require('express');
const busboy = require('connect-busboy');
const https = require('https');
const csvjson = require('csvjson');
const fs = require('fs');
const _ = require('lodash');
const app = express();
const config = {
  praatScript: __dirname + '/praat-script/',
  uploadPath: 'public/upload/',
  ca: 'ssl/fullchain.pem',
  key: 'ssl/privkey.pem',
  cert: 'ssl/cert.pem'
};
const sslOptions = {
  ca: fs.readFileSync(config.ca),
  key: fs.readFileSync(config.key),
  cert: fs.readFileSync(config.cert)
};

const analyzePitch = (filename) => {
  const filePath = __dirname + '/' + config.uploadPath;
  const praatScript = config.praatScript;

  exec('praat --run ' + praatScript + 'extractPitchIntensity.praat "' + filePath + '" "' + filename + '"', {stdio:[0,1,2]});
  exec('praat --run ' + praatScript + 'pitchIntensityScript.praat "' + filePath + '" "' + filename + '"', {stdio:[0,1,2]});
  const data = fs.readFileSync(config.uploadPath + filename + '.graph', {encoding : 'utf8'});
  return csvjson.toColumnArray(data, {
    delimiter: '\t',
    quote: '"'
  });
}

app.use(express.static('public'));

app.post('/upload', (req, res) => {
  const date = new Date();
  const filename = date.getTime() + '.wav';

  req.pipe(fs.createWriteStream(config.uploadPath + filename))
    .on('error', (e) => res.status(500).json({success: false, message: e.message}).end())
    .on('close', () => res.json({success: true, file: date.getTime()}))
});

app.get('/analyze/:filename', (req, res) => {
  res.json(analyzePitch(req.params.filename));
});

app.get('/questions', (req, res) => {
  res.json(JSON.parse(fs.readFileSync('./questions.json')));
});

app.get('/chart/:filename', (req, res) => {
  const data = fs.readFileSync(config.uploadPath + req.params.filename + '.graph', {encoding : 'utf8'});
  const jsonData = csvjson.toColumnArray(data, {
    delimiter: '\t',
    quote: '"'
  });
  res.json(jsonData);
});

app.get('/questions/:level/:count', (req, res) => {
  let questionsList = JSON.parse(fs.readFileSync('./questions.json'));

  questionsList = _.filter(questionsList, {level: req.params.level});
  res.json(_.sampleSize(questionsList, req.params.count));
});

app.post('/questions/', busboy({immediate: true}), (req, res) => {
  const busboy = req.busboy;
  const question = {};
  const questionsList = JSON.parse(fs.readFileSync('./questions.json'));
  let fstream;

  if (busboy) {
    busboy.on('file', function (fieldname, file, filename) {
      question.file = filename;
      fstream = fs.createWriteStream(config.uploadPath + filename);
      file.pipe(fstream);
      fstream.on('close', function () {});
    });

    busboy.on('field', function (fieldname, val) {
      switch (fieldname) {
        case 'question':
          question.question = val;
          break;
        case 'level':
          question.level = val;
          break;
      }
    });

    busboy.on('finish', function () {
      questionsList.push(question);
      fs.writeFile('./questions.json', JSON.stringify(questionsList, null, 2), function(){});
      analyzePitch(question.file.replace('.wav', ''));
      res.redirect('back');
    });

  } else {
    res.json({'result': false, 'message': 'no req.busboy'});
  }
});

https.createServer(sslOptions, app).listen(3000, function () {
  console.log('Listening on port 3000');
});