batchUrlChecks.js

const https = require("https");
const util = require("util");

// Adapted from https://gist.github.com/krnlde/797e5e0a6f12cc9bd563123756fc101f
https.get[util.promisify.custom] = function getAsync(options) {
  return new Promise((resolve, reject) => {
    https
      .get(options, (response) => {
        response.end = new Promise((resolve) => response.on("end", resolve));
        resolve(response);
      })
      .on("error", reject);
  });
};

const get = util.promisify(https.get);

const sleep = (time) => {
  return new Promise((resolve) => setTimeout(resolve, time));
};

const urls = [
  "https://www.example.com/",
  "https://www.example.org/",
  "https://www.example.net/",
  "invalid4",
  "https://www.example.com/",
  "https://www.example.org/",
  "https://www.example.net/",
  "invalid8",
  "https://www.example.com/",
  "https://www.example.org/",
  "https://www.example.net/",
  "invalid12",
  "https://www.example.com/",
  "https://www.example.org/",
  "https://www.example.net/",
  "invalid16",
];

const run = async (urls) => {
  const results = await Promise.all(
    urls.map(async (url) => {
      try {
        const response = await get(url);
        return [response.statusCode, url];
      } catch (e) {
        return [`ERR ${e.message}`, url];
      }
    })
  );

  results.map((res) => {
    console.log(res[0], res[1]);
  });
};

const runInBatches = async ({ urls, batchSize, delayMs }) => {
  while (urls.length > 0) {
    nextBatch = urls.splice(0, batchSize);
    await run(nextBatch);
    await sleep(delayMs);
  }
};

runInBatches({ urls, batchSize: 5, delayMs: 1000 });

/**
Output looks like:

> node batchUrlChecks.js
200 https://www.example.com/
200 https://www.example.org/
200 https://www.example.net/
ERR Invalid URL invalid4
200 https://www.example.com/
200 https://www.example.org/
200 https://www.example.net/
ERR Invalid URL invalid8
200 https://www.example.com/
200 https://www.example.org/
200 https://www.example.net/
ERR Invalid URL invalid12
200 https://www.example.com/
200 https://www.example.org/
200 https://www.example.net/
ERR Invalid URL invalid16
*/