Notion 自訂網域的程式碼，此段程式碼可讓 Cloudflare 串接個人 Notion Page，達到自訂 Notion 網域與網址的效果，請將此段程式碼貼到你的 Cloudflare Worker 編輯器內。更詳細的操作教學請參考 https://jcshawn.com/notion-custom-domain/

worker.js

/* 
 * Modifired via https://github.com/stephenou/fruitionsite/blob/master/worker.js 
 * This code is baesd on Fruitonsite service, localized by Chun Shawn in Traditional-Chinese.
 * You're able to set a custom domain with this code by using Cloudflare
 * Check for https://fruitionsite.com/ for toturials.
 * 
 * < Notion 自訂網域 Cloudflare 程式碼分享 >
 * 
 * 此程式由 Fruitonsite 製作（ https://fruitionsite.com/ ）
 * 由張君祥 Chun Shawn 翻譯繁體中文（ https://jcshawn.com ）
 * 將此程式碼加入到你的 Cloudflare Workers 路由設定，就可以將 Notion 連結改為你的個人網域
 * 請依照說明依序設定，歡迎參考翻譯者寫的手把手設定教學（ https://jcshawn.com/notion-custom-domain/ ）
 * 
 */

/* Notion 自定網域個人化設定開始 */

/* 第一步：在引號填入你的 Custom Domain，例如 jcshawn.com */
const MY_DOMAIN = "teachers-bar.com";

/*
 * 第二步。填入不想有英數結尾的 Notion Page 連結 ID ( xxx.notion.site/... 後面的字串就是代碼 )
 * 左側的字詞是你要自訂的連結代號，不用加引號
 * 右側要在引號填入相對應的 Notion page ID
 * 舉例來說，about : "jughew2oi31u9u302prjdf"，相對應的網址就是 jcshawn.com/about
 * 第一行爲主網址，只需填寫主頁的 Page ID，不用每一個 page 都填寫
 */

const SLUG_TO_PAGE = {
  "": "6de78fbc608440108ee70b2e713f2e1e",
  thanks: "9d9864f5338b47b0a7f42e0f0e2bbf46",
  showcase: "92053970e5084019ac096d2df7e7f440",
  roadmap: "7d4b21bfb4534364972e8bf9f68c2c36"
};

/* 第三步：分別輸入你的 SEO 標題與說明 */
const PAGE_TITLE = "這裡填寫網頁標題";
const PAGE_DESCRIPTION =
  "這裡寫網頁說明";

/* 第四步 : 自訂 Google Fonts 來做網頁字體，這裡我用支援中文的思源黑體，若要自訂請參考：https://fonts.google.com */
const GOOGLE_FONT = "Noto Sans TC";

/* 第五步：填入你的自訂 <script>，無此需求可略過 */
const CUSTOM_SCRIPT = ``;

/* Notion 自訂網域個人化結束，請勿更動下方的程式碼 */

const PAGE_TO_SLUG = {};
const slugs = [];
const pages = [];
Object.keys(SLUG_TO_PAGE).forEach(slug => {
  const page = SLUG_TO_PAGE[slug];
  slugs.push(slug);
  pages.push(page);
  PAGE_TO_SLUG[page] = slug;
});

addEventListener("fetch", event => {
  event.respondWith(fetchAndApply(event.request));
});

function generateSitemap() {
  let sitemap = '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">';
  slugs.forEach(
    (slug) =>
      (sitemap +=
        "<url><loc>https://" + MY_DOMAIN + "/" + slug + "</loc></url>")
  );
  sitemap += "</urlset>";
  return sitemap;
}

const corsHeaders = {
  "Access-Control-Allow-Origin": "*",
  "Access-Control-Allow-Methods": "GET, HEAD, POST, PUT, OPTIONS",
  "Access-Control-Allow-Headers": "Content-Type"
};

function handleOptions(request) {
  if (
    request.headers.get("Origin") !== null &&
    request.headers.get("Access-Control-Request-Method") !== null &&
    request.headers.get("Access-Control-Request-Headers") !== null
  ) {
    // Handle CORS pre-flight request.
    return new Response(null, {
      headers: corsHeaders
    });
  } else {
    // Handle standard OPTIONS request.
    return new Response(null, {
      headers: {
        Allow: "GET, HEAD, POST, PUT, OPTIONS"
      }
    });
  }
}

async function fetchAndApply(request) {
  if (request.method === "OPTIONS") {
    return handleOptions(request);
  }
  let url = new URL(request.url);
  url.hostname = 'www.notion.so';
  if (url.pathname === "/robots.txt") {
    return new Response("Sitemap: https://" + MY_DOMAIN + "/sitemap.xml");
  }
  if (url.pathname === "/sitemap.xml") {
    let response = new Response(generateSitemap());
    response.headers.set("content-type", "application/xml");
    return response;
  }
  let response;
  if (url.pathname.startsWith("/app") && url.pathname.endsWith("js")) {
    response = await fetch(url.toString());
    let body = await response.text();
    response = new Response(
      body
        .replace(/www.notion.so/g, MY_DOMAIN)
        .replace(/notion.so/g, MY_DOMAIN),
      response
    );
    response.headers.set("Content-Type", "application/x-javascript");
    return response;
  } else if (url.pathname.startsWith("/api")) {
    // Forward API
    response = await fetch(url.toString(), {
      body: url.pathname.startsWith('/api/v3/getPublicPageData') ? null : request.body,
      headers: {
        "content-type": "application/json;charset=UTF-8",
        "user-agent":
          "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.163 Safari/537.36"
      },
      method: "POST"
    });
    response = new Response(response.body, response);
    response.headers.set("Access-Control-Allow-Origin", "*");
    return response;
  } else if (slugs.indexOf(url.pathname.slice(1)) > -1) {
    const pageId = SLUG_TO_PAGE[url.pathname.slice(1)];
    return Response.redirect("https://" + MY_DOMAIN + "/" + pageId, 301);
  } else if (
    pages.indexOf(url.pathname.slice(1)) === -1 &&
    url.pathname.slice(1).match(/[0-9a-f]{32}/)
  ) {
    return Response.redirect('https://' + MY_DOMAIN, 301);
  } else {
    response = await fetch(url.toString(), {
      body: request.body,
      headers: request.headers,
      method: request.method
    });
    response = new Response(response.body, response);
    response.headers.delete("Content-Security-Policy");
    response.headers.delete("X-Content-Security-Policy");
  }

  return appendJavascript(response, SLUG_TO_PAGE);
}

class MetaRewriter {
  element(element) {
    if (PAGE_TITLE !== "") {
      if (
        element.getAttribute("property") === "og:title" ||
        element.getAttribute("name") === "twitter:title"
      ) {
        element.setAttribute("content", PAGE_TITLE);
      }
      if (element.tagName === "title") {
        element.setInnerContent(PAGE_TITLE);
      }
    }
    if (PAGE_DESCRIPTION !== "") {
      if (
        element.getAttribute("name") === "description" ||
        element.getAttribute("property") === "og:description" ||
        element.getAttribute("name") === "twitter:description"
      ) {
        element.setAttribute("content", PAGE_DESCRIPTION);
      }
    }
    if (
      element.getAttribute("property") === "og:url" ||
      element.getAttribute("name") === "twitter:url"
    ) {
      element.setAttribute("content", MY_DOMAIN);
    }
    if (element.getAttribute("name") === "apple-itunes-app") {
      element.remove();
    }
  }
}

class HeadRewriter {
  element(element) {
    if (GOOGLE_FONT !== "") {
      element.append(
        `<link href='https://fonts.googleapis.com/css?family=${GOOGLE_FONT.replace(' ', '+')}:Regular,Bold,Italic&display=swap' rel='stylesheet'>
        <style>* { font-family: "${GOOGLE_FONT}" !important; }</style>`,
        {
          html: true
        }
      );
    }
    element.append(
      `<style>
      div.notion-topbar > div > div:nth-child(3) { display: none !important; }
      div.notion-topbar > div > div:nth-child(4) { display: none !important; }
      div.notion-topbar > div > div:nth-child(5) { display: none !important; }
      div.notion-topbar > div > div:nth-child(6) { display: none !important; }
      div.notion-topbar-mobile > div:nth-child(3) { display: none !important; }
      div.notion-topbar-mobile > div:nth-child(4) { display: none !important; }
      div.notion-topbar > div > div:nth-child(1n).toggle-mode { display: block !important; }
      div.notion-topbar-mobile > div:nth-child(1n).toggle-mode { display: block !important; }
      </style>`,
      {
        html: true
      }
    );
  }
}

class BodyRewriter {
  constructor(SLUG_TO_PAGE) {
    this.SLUG_TO_PAGE = SLUG_TO_PAGE;
  }
  element(element) {
    element.append(
      `<script>
      window.CONFIG.domainBaseUrl = 'https://${MY_DOMAIN}';
      const SLUG_TO_PAGE = ${JSON.stringify(this.SLUG_TO_PAGE)};
      const PAGE_TO_SLUG = {};
      const slugs = [];
      const pages = [];
      const el = document.createElement('div');
      let redirected = false;
      Object.keys(SLUG_TO_PAGE).forEach(slug => {
        const page = SLUG_TO_PAGE[slug];
        slugs.push(slug);
        pages.push(page);
        PAGE_TO_SLUG[page] = slug;
      });
      function getPage() {
        return location.pathname.slice(-32);
      }
      function getSlug() {
        return location.pathname.slice(1);
      }
      function updateSlug() {
        const slug = PAGE_TO_SLUG[getPage()];
        if (slug != null) {
          history.replaceState(history.state, '', '/' + slug);
        }
      }
      function onDark() {
        el.innerHTML = '<div title="Change to Light Mode" style="margin-left: auto; margin-right: 14px; min-width: 0px;"><div role="button" tabindex="0" style="user-select: none; transition: background 120ms ease-in 0s; cursor: pointer; border-radius: 44px;"><div style="display: flex; flex-shrink: 0; height: 14px; width: 26px; border-radius: 44px; padding: 2px; box-sizing: content-box; background: rgb(46, 170, 220); transition: background 200ms ease 0s, box-shadow 200ms ease 0s;"><div style="width: 14px; height: 14px; border-radius: 44px; background: white; transition: transform 200ms ease-out 0s, background 200ms ease-out 0s; transform: translateX(12px) translateY(0px);"></div></div></div></div>';
        document.body.classList.add('dark');
        __console.environment.ThemeStore.setState({ mode: 'dark' });
      };
      function onLight() {
        el.innerHTML = '<div title="Change to Dark Mode" style="margin-left: auto; margin-right: 14px; min-width: 0px;"><div role="button" tabindex="0" style="user-select: none; transition: background 120ms ease-in 0s; cursor: pointer; border-radius: 44px;"><div style="display: flex; flex-shrink: 0; height: 14px; width: 26px; border-radius: 44px; padding: 2px; box-sizing: content-box; background: rgba(135, 131, 120, 0.3); transition: background 200ms ease 0s, box-shadow 200ms ease 0s;"><div style="width: 14px; height: 14px; border-radius: 44px; background: white; transition: transform 200ms ease-out 0s, background 200ms ease-out 0s; transform: translateX(0px) translateY(0px);"></div></div></div></div>';
        document.body.classList.remove('dark');
        __console.environment.ThemeStore.setState({ mode: 'light' });
      }
      function toggle() {
        if (document.body.classList.contains('dark')) {
          onLight();
        } else {
          onDark();
        }
      }
      function addDarkModeButton(device) {
        const nav = device === 'web' ? document.querySelector('.notion-topbar').firstChild : document.querySelector('.notion-topbar-mobile');
        el.className = 'toggle-mode';
        el.addEventListener('click', toggle);
        nav.appendChild(el);
        // enable smart dark mode based on user-preference
        if (window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches) {
            onDark();
        } else {
            onLight();
        }
        // try to detect if user-preference change
        window.matchMedia('(prefers-color-scheme: dark)').addEventListener('change', e => {
            toggle();
        });
      }
      const observer = new MutationObserver(function() {
        if (redirected) return;
        const nav = document.querySelector('.notion-topbar');
        const mobileNav = document.querySelector('.notion-topbar-mobile');
        if (nav && nav.firstChild && nav.firstChild.firstChild
          || mobileNav && mobileNav.firstChild) {
          redirected = true;
          updateSlug();
          addDarkModeButton(nav ? 'web' : 'mobile');
          const onpopstate = window.onpopstate;
          window.onpopstate = function() {
            if (slugs.includes(getSlug())) {
              const page = SLUG_TO_PAGE[getSlug()];
              if (page) {
                history.replaceState(history.state, 'bypass', '/' + page);
              }
            }
            onpopstate.apply(this, [].slice.call(arguments));
            updateSlug();
          };
        }
      });
      observer.observe(document.querySelector('#notion-app'), {
        childList: true,
        subtree: true,
      });
      const replaceState = window.history.replaceState;
      window.history.replaceState = function(state) {
        if (arguments[1] !== 'bypass' && slugs.includes(getSlug())) return;
        return replaceState.apply(window.history, arguments);
      };
      const pushState = window.history.pushState;
      window.history.pushState = function(state) {
        const dest = new URL(location.protocol + location.host + arguments[2]);
        const id = dest.pathname.slice(-32);
        if (pages.includes(id)) {
          arguments[2] = '/' + PAGE_TO_SLUG[id];
        }
        return pushState.apply(window.history, arguments);
      };
      const open = window.XMLHttpRequest.prototype.open;
      window.XMLHttpRequest.prototype.open = function() {
        arguments[1] = arguments[1].replace('${MY_DOMAIN}', 'www.notion.so');
        return open.apply(this, [].slice.call(arguments));
      };
    </script>${CUSTOM_SCRIPT}`,
      {
        html: true
      }
    );
  }
}

async function appendJavascript(res, SLUG_TO_PAGE) {
  return new HTMLRewriter()
    .on("title", new MetaRewriter())
    .on("meta", new MetaRewriter())
    .on("head", new HeadRewriter())
    .on("body", new BodyRewriter(SLUG_TO_PAGE))
    .transform(res);
}