a simple node.js scraper for automatically checking item availability on perfectcircuit.com

perfect-circuit-scraper.js

const puppeteer = require("puppeteer");

const URLS = [
  "https://www.perfectcircuit.com/intellijel-zeroscope-1u.html", // Zeroscope Oscilloscope 1U
  "https://www.perfectcircuit.com/expert-sleepers-es-8.html", // ES-8 USB Audio Interface
  "https://www.perfectcircuit.com/4ms-pingable-envelope-generator.html", // Pingable Envelope Generator
  "https://www.perfectcircuit.com/make-noise-erbe-verb-dsp-reverb-module.html", // Erbe-Verb DSP Reverb
  "https://www.perfectcircuit.com/xaoc-devices-batumi-model-1974.html", // Batumi Quad LFO
  "https://www.perfectcircuit.com/intellijel-shifty.html", // Intellijel Shifty
  "https://www.perfectcircuit.com/eowave-domino.html", // Eowave Domino Full Synth Voice
  "https://www.perfectcircuit.com/addac-603.html", // ADDAC603 VC Triple Bandpass Filter
  "https://www.perfectcircuit.com/wmd-performance-mixer.html", // WMD Performance Mixer
  "https://www.perfectcircuit.com/expert-sleepers-super-disting-ex-plus-alpha.html", // Super Disting EX Plus Alpha
];

const getPage = async () => {
  const browser = await puppeteer.launch();
  const close = () => browser.close();
  return { browser, close };
};

const parseAvailabilityFromPage = (browser) => async (url) => {
  const page = await browser.newPage();
  await page.goto(url);

  // Execute code in the DOM
  const data = await page.evaluate((url) => {
    const availabilityNode = document.querySelector(
      ".product-info-main .amstockstatus em"
    );

    const status = availabilityNode && availabilityNode.innerText;
    if (!status) {
      throw new Error(`No matching availability selector for ${url}`);
    }

    const nameNode = document.querySelector("h1.page-title");
    const name = nameNode && nameNode.innerText.replace("\n", " ");

    return { name, status, url };
  }, url);

  return data;
};

const scrapeUrls = async (page) => {
  return Promise.all(URLS.map(parseAvailabilityFromPage(page)));
};

const main = async () => {
  const { browser, close } = await getPage();

  try {
    const data = await scrapeUrls(browser);
    const results = data.reduce((acc, { name, status, url }) => {
      if (!acc[status]) {
        acc[status] = {};
      }
      acc[status][name] = url;
      return acc;
    }, {});
    console.log(results);
  } catch (err) {
    console.error(err);
  }

  await close();
};

main();