codewars tagger

codewars-tagger.js

// This script programmatically adjusts tags on Codewars kata
// list of untagged kata: https://www.codewars.com/kata/search?untagged

const puppeteer = require("puppeteer"); // ^20.2.0

let browser;
(async () => {
  ////////////////////////////////////////////////////////////////////

  // SETUP STEP 1: Set headless: false temporarily and log in manually.
  // Credentials will be stored in the browserdata dir.
  // After you're logged in, go back to headless: true (or "new").
  browser = await puppeteer.launch({
    headless: true,
    userDataDir: "browserdata",
  });

  // SETUP STEP 2: Manually create an empty collection
  // and fill in the information below.
  // This doesn't work in parallel; I would have to
  // create a new unique list per operation to do so,
  // which is possible, but fussy and unreliable.
  const collectionId = "62bf1595222562003e960b5b";
  const collectionName = "adjust-tags";

  // SETUP STEP 3: configure the kata and the tag operation.
  // (these should eventually be moved to params, args or file input)
  const kataId = "6459aa9aedc6d8004b348a16";
  const postAction = {
    op: "add", // "add" or "remove" tag(s)

    // tags from https://www.codewars.com/tags lowercased:
    tags: ["algorithms", "strings"],
  };

  ////////////////////////////////////////////////////////////////////

  const baseUrl = "https://www.codewars.com/";

  // navigate to the kata page and add it to the dummy collection
  const [page] = await browser.pages();
  await page.goto(baseUrl + "kata/" + kataId, {
    waitUntil: "domcontentloaded",
  });
  const addToColl = await page.waitForSelector(
    ".js-add-to-collection"
  );
  await addToColl.click();

  // poll until the modal opens and find the
  // row that matches our dummy collection
  const el = await page.waitForFunction(
    collectionId =>
      [...document.querySelectorAll(".collections li")].find(
        el =>
          el
            .querySelector("a")
            .href.includes(collectionId)
      ),
    {timeout: 10_000},
    collectionId
  );

  // click the button to add the item to the collection
  await el.evaluate(el => {
    if (
      el
        .querySelector(".btn")
        ?.textContent.toLowerCase()
        .trim() === "add"
    ) {
      el.querySelector(".btn").click();
    }
  });

  // wait for the 'add' button to change to 'remove'
  await page.waitForFunction(
    collectionId =>
      [...document.querySelectorAll(".collections li")]
        .find(el =>
          el
            .querySelector(".info-row a")
            .href.includes(collectionId)
        )
        ?.textContent.toLowerCase()
        .includes("remove"),
    {timeout: 10_001},
    collectionId
  );

  // navigate to the collection and check to see if
  // the removal button for the item we added is ready
  await page.goto(baseUrl + "collections/" + collectionName, {
    waitUntil: "domcontentloaded",
  });

  let removeBtn;
  try {
    removeBtn = await page.waitForSelector(".remove.js-remove", {
      timeout: 5_000,
    });
  } catch (err) {
    // if navigation beat the element, try refreshing
    await page.goto(baseUrl + "collections/" + collectionName, {
      waitUntil: "domcontentloaded",
    });
    removeBtn = await page.waitForSelector(".remove.js-remove", {
      timeout: 5_000,
    });
  }

  // ensure there is exactly 1 item in the collection
  const hasMultipleButtons = await page.evaluate(
    () =>
      document.querySelectorAll(".remove.js-remove").length !== 1
  );
  if (hasMultipleButtons) {
    throw Error("Found multiple challenges in the collection");
  }

  // click the add tags button and inject our POST action
  // rather than messing with tagging in the DOM
  let resolve = null;
  const reqP = new Promise(res => {
    resolve = res;
  });
  const handleRequest = async request => {
    if (/\/item-tags$/.test(request.url())) {
      const data = {
        method: "POST",
        headers: {...request.headers()},
        postData: JSON.stringify({
          ...JSON.parse(request.postData()),
          ...postAction,
        }),
      };
      request.continue(data);
      resolve();
    } else {
      request.continue();
    }
  };
  await page.setRequestInterception(true);
  page.on("request", handleRequest);
  const addBtn = await page.waitForSelector(
    '[data-action="click->collection#addTags"]'
  );
  await addBtn.click();
  await reqP;
  page.off("request", handleRequest);
  await page.setRequestInterception(false);

  // remove the new kata; it's temporary
  await removeBtn.evaluate(el => el.click());
  await page.evaluate(() =>
    document.querySelector(".remove.js-remove")?.click()
  );
  const confirmBtn = await page.waitForFunction(
    () =>
      [...document.querySelectorAll(".modal-footer .btn")].find(
        el => el.textContent.toLowerCase().includes("remove")
      ),
    {timeout: 10_001}
  );
  await confirmBtn.evaluate(el => el.click());

  // final check to make sure the collection is empty
  await page.goto(baseUrl + "collections/" + collectionName, {
    waitUntil: "domcontentloaded",
  });
  try {
    await page.waitForFunction(
      `!document.querySelector(".remove.js-remove")`,
      {timeout: 10_002}
    );
  } catch (err) {
    // refresh to see if the item has been removed
    await page.goto(baseUrl + "collections/" + collectionName, {
      waitUntil: "domcontentloaded",
    });
    await page.waitForFunction(
      `!document.querySelector(".remove.js-remove")`,
      {timeout: 10_003}
    );
  }
})()
  .catch(err => console.error(err))
  .finally(() => browser?.close());