Vite Plugins

Versed in the JavaScript and Node ecosystem? Fan of Gleam & Vite? Interested of building polyglot projects? Those Plugins are here to help you build your dream project, with Gleam, Redraw or Node & TypeScript integrations.
They provide integrations between Gleam & Vite, simplify Gleam & React integration & help with package.json imports for your sub-packages, like in monorepo.

Installation

yarn add @chouquette/vite

Using Vite Gleam Plugin

Based on the fantastic work of Enderchief, you can easily integrate Gleam & Vite together. Create your Vite project with yarn create vite. Once it's done, create a new Gleam project inside your newly-created Vite project. Finally, inside your vite.config.js, import the plugin and inject it.

// vite.config.{ts,js}
import gleam from "@chouquette/vite/gleam"
export default {
  plugins: [gleam()],
}

[!INFO]

By default, TypeScript will complain about importing files with the .gleam extension. There are two choices for fixes:

• If the type of the import doesn't matter , add declare module "*.gleam"; inside any TypeScript file. A caveat is the LSP does not know if an export exists so it will not provide autocompletion when importing a Gleam file and it will type exports as any.
• Alternatively, if the vite dev server is running you can have full type safety when importing from Gleam. npm i ts-gleam. Create a tsconfig.json/jsconfig.json and set compilerOptions.plugins to [{"name": "ts-gleam"}] (RECOMMENDED)

Using Redraw Plugin

When using Redraw, you regularly need to interact with the Gleam FFI, and using JSX is often needed to integrate easily with existing React packages. The Redraw plugin add custom matcher for Vite, to add JSX support in Gleam FFI files. Indeed, in modern Vite installations, only .jsx files convert your JSX to JavaScript. With this plugin, all files ending in .redraw.js, .redraw.mjs, .redraw.ts & .redraw.mts will run through a modern JSX transformer to support FFI with React!

// vite.config.{ts,js}
import redraw from "@chouquette/vite/redraw"
export default {
  plugins: [redraw()],
}

Once the plugin has been added, you're now free to add FFI code with JSX.

// file.redraw.mjs
export function component() {
  return (
    <React.Fragment>
      <div>Gleam + React = 💜</div>
    </React.Fragment>
  )
}

Using Packages Plugin

With recent package.json, you can use sub-path imports. They're a standardised way to work Node & JavaScript packages, and they integrate perfectly with TypeScript and other JavaScript packages. However, when using Gleam, JavaScript files are simply copy-pasted as-is, and the paths won't be rewritten. For example, let's say you write your FFI like this.

// package.json
// Define an import path pointing to the Gleam prelude.
// The Gleam `build` folder is always at root of the project, alongside the
// `gleam.toml` file. If you put your `package.json` alongside them, the
// sub-path will always resolve correctly.
{
  "imports": {
    "#gleam/prelude": "./build/dev/javascript/prelude.mjs",
  },
}

//// module.gleam
//// Add an FFI function here, calling directly JavaScript. With the defined
//// API from Gleam, it's possible to directly call and return Gleam data
//// from JavaScript.

/// Divide a number by `y`, iif `y` is different from 0.
@external(javascript, "./module.ffi.mjs", "divide")
pub fn divide(x: Int, y: Int) -> Result(Int, Nil)

// module.ffi.mjs
// Import the prelude, to access Result type directly.
import * as gleam from "#gleam/prelude"
// Define the JavaScript FFI function.
export function divide(x, y) {
  if (y === 0) return gleam.Result$Error()
  const result = x / y
  return gleam.Result$Ok(result)
}

In your project, this will work correctly if you launch your program with Node. Node will correctly resolve the imports. Unfortunately, if your package is used as dependency, let's with path dependency in a monorepo, your project will not be able to access the package.json imports field, and the resolution will fail. The plugin, when called, will search for your local imports, and add them automatically to your project. Be careful though, you cannot have two imports with the same name, but with different resolutions. In that case, the plugin will fail & warn you.

// vite.config.{ts,js}
import packages from "@chouquette/vite/packages"
export default {
  resolve: {
    // Resolve the aliases from TypeScript config files and NPM imports.
    alias: await packages.aliases(__dirname),
  },
}

Thanks

Special thanks to Enderchief, who made the awesome initial effort to create vite-gleam, which has been the foundations for @chouquette/vite/gleam. That package does not replace vite-gleam, but instead provides an alternative and a coherent package including Redraw, Gleam and other Node niceties directly built together.