Nunjucks for Hono

Adds support for the Nunjucks templating engine to Hono. Traditional templating engines do not work on serverless runtimes such as Cloudflare Workers because they rely on file system APIs and dynamic code evaluation.

Nunjacks is a templating engine with a neat feature which allows it to precompile templates to plain JavaScript. This code can then be loaded as a regular module and passed into the engine. This library just contains a little bit of glue to make working with it more pleasant.

npm add hono-nunjucks

Usage

1. Create a Nunjucks template within your project. Say "src/templates/hello.html".

<strong>Hello {{ username }}!</strong>

2. Compile the template into JavaScript.

npx hono-nunjucks-precompile src/templates src/precompiled.mjs

If you're using Wrangler, you can add a custom build step to watch the "src/ template" directory and automatically precompile & restart on any changes. Do not put the precompiled result to the template's directory to avoid a reload cycle.

[build]
command = "npx hono-nunjucks-precompile src/templates src/precompiled.mjs"
cwd = "."
watch_dir = "src/templates"

3. Import the "src/compiled.mjs" file and pass it to the middleware.

import { installNunjucks } from "hono-nunjucks";
import templates from "./src/precompiled.mjs";

app.use(
  "*",
  installNunjucks({
    templates
  })
);

Doing it like this ensures that the server is automatically restarted on changes and also that the precompiled templates are included in the resulting bundle (again assuming Cloudflare Workers).

4. Use the template in your code. Note that the extension is automatically stripped from the name.

async function home(c: Context) {
  // t is automatically added by the middleware
  const t = c.get("t");

  // Render the template to string (hello.html -> hello)
  const rendered = t.render("hello", { username: "rumburak" });

  // Send it as HTML
  return c.html(rendered);
}

5. Have a look at the documentation to see all of the available goodies.

License

ICS