HN Article Search

hn-article-search.user.js

// ==UserScript==
// @name         HN Article Search
// @namespace    http://tampermonkey.net/
// @version      1.0.0
// @match        *://*/*
// @grant        GM_registerMenuCommand
// @grant        GM_unregisterMenuCommand
// @grant        GM_openInTab
// @grant        GM_xmlhttpRequest
// @connect      hn.algolia.com
// ==/UserScript==

(function () {
  "use strict";

  // Exit if running in an iframe
  if (window.self !== window.top) {
    return;
  }

  function canonicalize(href) {
    try {
      const u = new URL(href);
      u.search = "";
      u.hash = "";
      u.hostname = u.hostname.replace(/^www\./, "");
      if (u.pathname.length > 1 && u.pathname.endsWith("/")) {
        u.pathname = u.pathname.slice(0, -1);
      }
      return u.toString();
    } catch {
      return href.split("?")[0].split("#")[0];
    }
  }

  // If we're on an HN item page, grab the submitted URL from the post itself
  function resolvePageUrl() {
    const loc = window.location;
    const isHNItem =
      (loc.hostname === "news.ycombinator.com" ||
        loc.hostname === "hn.algolia.com") &&
      loc.pathname === "/item";

    if (isHNItem) {
      // The submitted link lives in .titleline > a on news.ycombinator.com
      const link = document.querySelector(
        ".titleline > a, .title > a.storylink",
      );
      if (link && link.href && !link.href.startsWith("item?")) {
        return link.href;
      }
      // Self-post (Ask HN, Show HN text post) — nothing to search for
      return null;
    }

    return loc.href;
  }

  const pageUrl = resolvePageUrl();
  if (!pageUrl) {
    // On an HN self-post; nothing meaningful to search
    return;
  }

  const canonical = canonicalize(pageUrl);
  const bareUrl = canonical.replace(/^https?:\/\//, "");

  const searchUrl = `https://hn.algolia.com/?q=${encodeURIComponent(bareUrl)}`;
  const apiUrl = `https://hn.algolia.com/api/v1/search?query=${encodeURIComponent(bareUrl)}&restrictSearchableAttributes=url`;

  let menuId = null;

  function openSearch() {
    GM_openInTab(searchUrl, { active: true, setParent: true });
  }

  function registerMenu(label) {
    if (menuId !== null && typeof GM_unregisterMenuCommand === "function") {
      try {
        GM_unregisterMenuCommand(menuId);
      } catch (e) {
        /* some managers don't support it reliably */
      }
    }
    menuId = GM_registerMenuCommand(label, openSearch);
  }

  registerMenu("Searching…");

  GM_xmlhttpRequest({
    method: "GET",
    url: apiUrl,
    timeout: 8000,
    onload: (res) => {
      try {
        const data = JSON.parse(res.responseText);
        const n = data.nbHits ?? 0;
        const label =
          n === 0 ? "No results" : `${n} result${n === 1 ? "" : "s"}`;
        registerMenu(label);
      } catch (e) {
        registerMenu("Search this page");
      }
    },
    onerror: () => registerMenu("Search this page"),
    ontimeout: () => registerMenu("Search this page"),
  });
})();

Video of how it works: https://cleanshot.com/share/bKjjp0WV