vite-plugin-assemblyscript-asc

Add a AssemblyScript codebase to a Vite project with full HMR support and debug with source maps. Integrate the resulting WebAssembly in your frontend using standard AssemblyScript ESM imports and the typical debug and release build variants mapped to vite dev and vite build.

Installation

Just install it as:

yarn add -D vite-plugin-assemblyscript-asc

Vite integration usage

vite.config.ts

import assemblyScriptPlugin from "vite-plugin-assemblyscript-asc"

export default defineConfig({
  plugins: [
    assemblyScriptPlugin()
  ]
})

Runtime WebAssembly integration usage

The WebAssembly module comes with ESM bindings generated automatically. Also, the WASM code is inlined and being instanciated synchronously:

src/index.ts

import { add } from './as/build/assembly'

console.log(add(3, 4)) // prints: '7'

Example project

If you'd like to copy & paste, the example folder contains a fully working example project layout.

Default project layout

The default plugin configuration assumes that the AssemblyScript codebase is located in src/as and that the generated WebAssembly module is stored as build/assembly.wasm:

dist/
  [Vite build files]
src/
  as/
    assembly/
      [AssemblyScript codebase]
    build/
      assembly.wasm
      assembly.wasm.map
    asconfig.json
    package.json
  [Your other code, non-AssemblyScript]

In asconfig.json it is assumed that you change outFile to build/assembly.wasm and textFile to build/assembly.wat so that you can import from a single file location and the Vite execution mode could determine the build variant:

src/as/asconfig.json

{
  "targets": {
    "debug": {
      "outFile": "build/assembly.wasm",
      "textFile": "build/assembly.wat",
      "sourceMap": true,
      "debug": true
    },
    "release": {
      "outFile": "build/assembly.wasm",
      "textFile": "build/assembly.wat",
      "sourceMap": true,
      "optimizeLevel": 3,
      "shrinkLevel": 0,
      "converge": false,
      "noAssert": false
    }
  },
  "options": {
    "bindings": "esm"
  }
}

Custom project layout

That's why the default config looks like this:

{
  projectRoot: 'src/as',
  configFile: 'asconfig.json',
  srcMatch: 'assembly',
  srcEntryFile: 'assembly/index.ts',
  targetWasmFile: 'build/assembly.wasm',
  distFolder: 'dist'
}

In case your project layout looks differently, make sure the paths are set-up accordingly, by providing the necessary configuration options:

vite.config.ts

import assemblyScriptPlugin from "vite-plugin-assemblyscript-asc"

export default defineConfig({
  plugins: [
    // let's assume the codebase is located somewhere else
    assemblyScriptPlugin({ projectRoot: 'packages/assemblyscript' })
  ]
})

Contributors

Thanks to Menci, the author of vite-plugin-wasm for providing a great project layout and e2e test code.