tableau_og_extension

// Copyright 2024 SavvyCal, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
const core = require("puppeteer-core");
const fs = require("fs");
const os = require("node:os");

const executablePath =
  process.platform === "win32"
    ? "C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe"
    : process.platform === "linux"
    ? "/usr/bin/google-chrome"
    : "/Applications/Google Chrome.app/Contents/MacOS/Google Chrome";

/**
 * Takes a rendered screenshot of an HTML page.
 *
 * @param {string} html - the contents of the page.
 * @param {boolean} isDev - whether we are in development mode.
 * @returns a Base64 encoded string of the screenshot.
 */
async function takeScreenshot(html) {
  let file;

  const browser = await core.launch({
    executablePath,
    headless: true,
    args: [
      "--disable-gpu",
      "--disable-dev-shm-usage",
      "--disable-setuid-sandbox",
      "--no-sandbox",
    ],
  });

  try {
    const page = await browser.newPage();

    // Set the viewport size to match standard open graph image cards
    await page.setViewport({ width: 1200, height: 630 });

    // Set the content to our rendered HTML
    await page.setContent(html, { waitUntil: "domcontentloaded" });

    // Wait until all images and fonts have loaded
    //
    // See: https://github.blog/2021-06-22-framework-building-open-graph-images/#some-performance-gotchas
    await page.evaluate(async () => {
      const selectors = Array.from(document.querySelectorAll("img"));
      await Promise.all([
        document.fonts.ready,
        ...selectors.map((img) => {
          // Image has already finished loading, let’s see if it worked
          if (img.complete) {
            // Image loaded and has presence
            if (img.naturalHeight !== 0) return;
            // Image failed, so it has no height
            throw new Error("Image failed to load");
          }
          // Image hasn’t loaded yet, added an event listener to know when it does
          return new Promise((resolve, reject) => {
            img.addEventListener("load", resolve);
            img.addEventListener("error", reject);
          });
        }),
      ]);
    });

    // Take the screenshot of the page
    file = await page.screenshot({ type: "png", encoding: "base64" });

    await page.close();
  } finally {
    await browser.close();
  }

  // Sometimes this fails with `ENOTEMPTY: directory not empty`. This is not
  // really supposed to happen, but I suspect when it does it's due to a race
  // condition of some kind where a directory is getting modified during the
  // recursive delete operation. We can just swallow this and figure it will
  // eventually succeed on subsequent requests. It might be a good idea to move
  // this into an Oban-managed cron task so that it won't affect the performance
  // of the screenshot process.
  try {
    deletePuppeteerProfiles();
  } catch {}

  return file;
}

/**
 * Delete puppeteer profiles from temp directory to free up space
 * See: https://github.com/puppeteer/puppeteer/issues/6414
 */
function deletePuppeteerProfiles() {
  const tmpdir = os.tmpdir();

  fs.readdirSync(tmpdir).forEach((file) => {
    if (file.startsWith("puppeteer_dev_chrome_profile")) {
      fs.rmSync(`/${tmpdir}/${file}`, { recursive: true, force: true });
    }
  });
}

module.exports = takeScreenshot;