11. 11
    Use waitUntil to perform work after Cloudflare Worker returns response
    1m 41s

Use waitUntil to perform work after Cloudflare Worker returns response

InstructorJon Meyers

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The waitUntil function allows us to continue performing work in our Cloudflare Worker, after a response has been sent back to the client.

In this lesson, we modify the revalidate route to send a response immediately, and then continue on to fetch new data and refresh our KV store.

Finally, we use the Thunder Client extension to simulate a POST request to the revalidate route, and confirm that this receives a response before the cache is updated.

Code Snippets

Update Revalidate route to respond immediately

router.post(
  "/revalidate",
  withContent,
  async (request, { SUPABASE_URL, SUPABASE_ANON_KEY, ARTICLES }, context) => {
    const updateCache = async () => {
      const { type, record, old_record } = request.content;
      const supabase = createClient(SUPABASE_URL, SUPABASE_ANON_KEY);

      if (type === "INSERT" || type === "UPDATE") {
        await writeTo(ARTICLES, `/articles/${record.id}`, record);
      }

      if (type === "DELETE") {
        await ARTICLES.delete(`/articles/${old_record.id}`);
      }

      const { data: articles } = await supabase.from("articles").select("*");
      await writeTo(ARTICLES, "/articles", articles);
      console.log("updated cache");
    };

    context.waitUntil(updateCache());

    console.log("sending response");

    return json({ received: true });
  }
);

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npx wrangler dev

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