downloads.js

import phantom from 'phantom';
import path from 'path';
import fs from 'fs-extra';
import klawSync from 'klaw-sync';
import config from 'config';
import logger from '../utils/logger';

const sourcePath = config.get('downloads');

const waitUntil = asyncFunc => new Promise((resolve, reject) => {
  const wait = () => {
    asyncFunc().then((value) => {
      if (value === true) {
        resolve();
      } else {
        setTimeout(wait, 100);
      }
    }).catch((e) => {
      reject(e);
    });
  }
  wait();
});

const clearFolder = folder =>
  process.nextTick(() => {
    const files = klawSync(folder, { nodir: true });
    for (const file of files) {
      fs.removeSync(file.path);
    }
  });

const renderScreenshot = async (input, output) => {
  const instance = await phantom.create();
  const page = await instance.createPage();

  await page.property('viewportSize', { width: 1024, height: 600 });
  await page.open(input);

  await waitUntil(() => page.evaluate(() => window.done));
  await page.render(output);
  await instance.exit();
};

const downloadResume = async (url, options = {}) => {
  const {
    title,
    folder
  } = options;
  const resultFloder = path.resolve(__dirname, sourcePath, folder);

  // makesure folder exist
  await fs.ensureDirSync(sourcePath);
  await fs.ensureDir(resultFloder);

  const filePath = path.resolve(resultFloder, title);
  const resultPath = `/downloads/${folder}/${title}`;
  logger.info(`[RESUME:DOWNLOAD:RENDER-PATH] ${filePath}`);

  if (fs.existsSync(filePath)) {
    return resultPath;
  }

  clearFolder(resultFloder);
  await renderScreenshot(url, filePath);
  return resultPath;
};

export default {
  resume: downloadResume
};