Cloudflare Pages + HTMX

This is a starter project to create a zero-build web-app using HTMX on Cloudflare. It uses _hyperscript for additional (rare) client side JS and TailwindCSS and DaisyUI for styling and theme.

$ git clone https://github.com/stukennedy/cloudflare-htmx.git
$ cd cloudflare-htmx
$ npm i
$ npm run dev

NextJS-style routing files, written in Typescript, are found in the functions folder.
Endpoints should return HTML strings wrapped in a new Response().
import { html, view } from "@lib/html" declaration allows a string template to be syntax highlighted in VS Code
Use _middleware.ts files at any level of the folder structure to apply a layout. You should use this to at least apply your root level HTML wrapper. e.g.

// functions/_middleware.ts
import RootLayout from '@layouts/RootLayout';
import { applyLayout } from '@lib/html';

export const onRequestGet = [applyLayout(RootLayout)];

This makes sure that the RootLayout which is of type LayoutFunction wraps all GET requests throughout the app. Our RootLayout.ts looks like this:

import SupabaseAuth from '@components/SupabaseAuth';
import { html, LayoutFunction } from '@lib/html';

// this is the layout for the entire site
const _layout: LayoutFunction = ({ children }) => {
  const title = 'Cloudflare Pages + HTMX + Hyperscript';
  return html`
    <!DOCTYPE html>
    <html lang="en" data-theme="mytheme">
      <head>
        <meta charset="utf-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1" />
        <title>${title}</title>
        <link href="/assets/css/output.css" rel="stylesheet" />
        <script src="/assets/js/htmx.min.js"></script>
        <script src="/assets/js/_hyperscript.min.js"></script>
      </head>
      <body class="bg-base-300" hx-boost="true">
        ${children}
        <div id="toaster"></div>
        <div id="modal"></div>
        ${SupabaseAuth('/dashboard')}
      </body>
    </html>
  `;
};
export default _layout;

A layout function can be async too if needed.

Other layouts can be handled a similar way throughout the folder structure. e.g. to Apply the Navbar to just anything under route /dashboard we use this

// functions/dashboard/_middleware.ts
import DashLayout from '@layouts/DashLayout';
import { applyLayout } from '@lib/html';
import { getSupabase } from '@model/supabase';

const authentication: PagesFunction = async ({ request, next }) => {
  const url = new URL(request.url);
  const supabase = await getSupabase(request);
  const {
    data: { user },
  } = await supabase.auth.getUser();
  if (!user) {
    console.error('authentication: redirect to login', url.origin);
    return Response.redirect(url.origin, 303);
  } else {
    return next();
  }
};

export const onRequestGet = [authentication, applyLayout(DashLayout)];

This chains both the authentication function and the layout. If the authentication fails, it redirects to the login screen before getting to process the layout.

HTMX

HTMX is a lightweight javascript library that encourages webapps to be built using HATEOAS.

HATEOAS (Hypermedia as the Engine of Application State) is a constraint of the REST application architecture. It keeps the REST style architecture unique from most other network application architectures.

This means we return HTML from every endpoint request and never JSON. HTMX makes it easy to trigger asynchronous requests for data e.g. directly from a button click or page load ... and then allows you the control on where to place the HTML that the backend responds with.