WASI TinyGo JS Helpers

Build TinyGo functions for Node.js thanks to WebAssembly and the Node.js WASI support.

• wasi-tinygo-js is both a npm package and a Golang library.
• Why TinyGo? It's the only Go compiler that can build WASI compliant wasm modules

Install

Node.js

npm install [email protected]

Go

import (
  "github.com/bots-garden/wasi-tinygo-js/wasihelpers"
)

Create and build a wasm module (with TinyGo)

package main

import (
	"github.com/bots-garden/wasi-tinygo-js/wasihelpers"
)

func main() {
	wasihelpers.SetHandler(Handler)
}

func Handler(param []byte) ([]byte, error) {

	message := "👋 Hello World 🌎" + string(param)
	return []byte(message), nil
}

Build:

tinygo build -o hello.wasm -target wasi ./hello.go

Call the TinyGo Wasm function from Node.js

import {WasmHelper, WasmModule} from 'wasi-tinygo-js'

(async () => {
  const wasm = await WasmHelper.compile("./hello.wasm")

  let wasmModule = new WasmModule(wasm)

  let success = await wasmModule.initialize()

  if(success) {

    let result = wasmModule.callHandlerWithString("John Doe")
    if(result.isError) {
      console.log("😡", result.toString())
    } else {
      console.log("🙂", result.toString())
    }
  }

})()

You can call the Go handler with 3 types:

• Bytes: wasmModule.callHandlerWithBytes(new TextEncoder("utf8").encode("John Doe"))
• String: wasmModule.callHandlerWithString("John Doe")
• JSON: wasmModule.callHandlerWithJson({firstName: "John", lastName: "Doe"})

The 3 callHandler methods return a BufferResult type:

classDiagram
  class BufferResult {
    +Uint8Array buffer
    +boolean isError
    +BufferResult constructor(Uint8Array, boolean)
    +string toString()
    +object toJson()
  }

👀 Have a look to the /samples directory

Call the TinyGo Wasm function with WasmEdge, Wasmtime or Wasmer

If you want to execute the TinyGo wasm module with a WebAssembly Runtime, it's simple, update the main function like this:

package main

import (
	"fmt"
	"github.com/bots-garden/wasi-tinygo-js/wasihelpers"
	"os"
	"path/filepath"
)

func main() {
	if filepath.Ext(os.Args[0]) == ".wasm" {
		value, _ := Handler([]byte(os.Args[1]))
		fmt.Println(string(value))
	} else {
		wasihelpers.SetHandler(Handler)
	}
}

func Handler(param []byte) ([]byte, error) {

	message := "👋 Hello World 🌎" + string(param)
	return []byte(message), nil
}

And now, you can run it like this:

wasmer wasm/hello.wasm "Jane"
wasmtime wasm/hello.wasm "Jane"
wasmedge wasm/hello.wasm "Jane"

Files

This is subject to change

👀 Have a look to the /samples/hello-world-text directory