scripts/download-images.js

/**
  Download images from a file containing URLS.

  The URL file must contain a single URL per line.
 */

const path = require("path");
const fs = require("fs");
const http = require("http");
const https = require("https");
const Stream = require("stream").Transform;

const inputFile = path.join(process.cwd(), process.argv[2]);
const outputDir = path.join(process.cwd(), process.argv[3]);
const basename = path.basename(inputFile);

const imageURLS = fs
  .readFileSync(inputFile, "utf8")
  .split("\n")
  .map(url => url.trim())
  .filter(url => url);

let successCount = 0;
let errorCount = 0;

function onEnd(err) {
  if (err) {
    errorCount += 1;
  } else {
    successCount += 1;
  }

  console.log(
    `${err ? "☠️" : "✅"}   ${successCount + errorCount} / ${imageURLS.length}`
  );

  if (successCount + errorCount === imageURLS.length) {
    console.log();
    console.log(`${errorCount} fail\n${successCount} success`);
    process.exit();
  }
}

imageURLS.forEach((url, i) => {
  const { request } = url.indexOf("http://github.com/mathieudutour/sketch-hotdog/blob/aa0219d05681188ba1ab43cb56497c728eb31a84/scripts/download-images.js") === 0 ? http : https;
  const ext = path.extname(url);
  const r = request(url.trim(), response => {
    const data = new Stream();

    response.on("data", chunk => {
      data.push(chunk);
    });

    response.on("error", onEnd);

    response.on("end", () => {
      fs.writeFileSync(
        path.join(outputDir, `${basename}_${i}${ext}`),
        data.read()
      );
      onEnd();
    });
  });

  r.on("error", onEnd);

  r.end();
});