Routes & Guards

Understanding how to define routes and guards

In jeasx, a file system-based routing system is at the heart of the framework. All routes are stored in the routes directory of your project and are functions that receive request and reply objects from Fastify as props. Routes can be written using JSX, but can also be written in JavaScript and/or TypeScript, so supported extensions are: .js(x)|.ts(x)

A route can return various types of payloads for the client, including HTML (default), JSON, or other formats. If you need to perform asynchronous operations, you can declare your route or imported components as async.

Named routes

The only rule for named routes is to enclose the base filename within brackets. This convention allows you to store components, services and utilities besides your routes without exposing them as endpoints.

Route path URL
src/routes/[index].jsx /
src/routes/a/b/[you-name-it].jsx /a/b/you-name-it
src/routes/company/[index].tsx /company
src/routes/images/[logo.svg].js /images/logo.svg
src/routes/api/posts/[update.json].ts /api/posts/update.json
src/routes/api/posts/utils/format.ts This file is not exposed as endpoint.

Code example

export default function FrontPage({ request, reply }) {
  const path = request.urlData().path;

  return (
      {"<!DOCTYPE html>"}
      <html lang="en">
        <base href={`${path.endsWith("/") ? path : path + "/"}`} />
        <title>Hello World</title>
        <h1>Hello World</h1>

Dynamic routes

Dynamic routes are wildcards designed to capture all requests for the current folder and its subfolders. They enable the creation of content with a dynamic URL structure, such as pages retrieved from a CMS. If a named route exists in the same folder as dynamic route, the named route will take precedence. The name for a dynamic route is fixed and must be: [...path](.jsx|.js|.tsx|.ts)

Route path URL
src/routes/blog/[...path].jsx /blog/article1

Code example

export default async function BlogPage({ request, reply }) {
  const segments = request.urlData().path.split("/");
  const product = await (await fetch(`${segments[1]}`)).json();

  if (product.message) {

  return (
    <Layout title={product.title} description={product.description}>


Guards enable you to intercept requests and are inherited from the root to the current folder. They are valuable for controlling access to a route. Typically, a guard does not return any payload, allowing the request to be handled by the next defined route. However, if a guard does return a payload, it will be delivered to the client, and no other route will be executed.

Route path URL
src/routes/blog/[...guard].jsx The code of the guard is executed before named or dynamic routes in the current folder or below.

Code example

export default function AuthorizationGuard({ request, reply }) {
  const authorization = request.headers["authorization"];
  if (
    authorization !== `Basic ${Buffer.from("demo:demo").toString("base64")}`
  ) {
    reply.header("WWW-Authenticate", 'Basic realm="Restricted Area');
    return (
      <Layout title="Error 401">
        <h1>Error 401</h1>
        <p>You are not allowed to view this page!</p>

Additionally, a guard has the capability to return an object, which will serve as props for all routes protected by the guard. This feature enables the creation of routes that are entirely independent from the request object, simplifying component testing.

export default function PropsGuard({ request }) {
  const body = request.body || {};
  return { message: body["message"] };
export default function MessageView({ message }) {
  return <p>{message ? message : "No message for you"}</p>;
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