Examples for running JavaScript in WasmEdge

These examples showcase how to run JavaScript programs with the WasmEdge binary tools. WasmEdge provides a lightweight sandbox for running and managing JavaScript applications. More examples are available in this Github repo.

Get qjs.wasm from the wasmedge-quickjs repo

The qjs.wasm can be found on the wasmedge-quickjs release page

Basic examples

The qjs.wasm is a JavaScript interpreter compiled into WebAssembly. Below is a very simple JavaScript example in WasmEdge.

$ wasmedge --dir .:. qjs.wasm hello.js 1 2 3
Hello 1 2 3

You can run an interactive JavaScript terminal (read-eval-print loop, or REPL) from the WasmEdge CLI.

$ wasmedge --dir .:. qjs.wasm repl.js
QuickJS - Type "\h" for help
qjs >

Tensorflow examples

The qjs_tf.wasm is a JavaScript interpreter with WasmEdge Tensorflow extension compiled into WebAssembly. To run qjs_tf.wasm, you must use the wasmedge-tensorflow-lite CLI tool, which is a build of WasmEdge with Tensorflow extension built-in. You can download a full Tensorflow-based JavaScript example to classify images.

# Download the Tensorflow example
$ wget https://raw.githubusercontent.com/second-state/wasmedge-quickjs/main/example_js/tensorflow_lite_demo/aiy_food_V1_labelmap.txt
$ wget https://raw.githubusercontent.com/second-state/wasmedge-quickjs/main/example_js/tensorflow_lite_demo/food.jpg
$ wget https://raw.githubusercontent.com/second-state/wasmedge-quickjs/main/example_js/tensorflow_lite_demo/lite-model_aiy_vision_classifier_food_V1_1.tflite
$ wget https://raw.githubusercontent.com/second-state/wasmedge-quickjs/main/example_js/tensorflow_lite_demo/main.js

$ wasmedge-tensorflow-lite --dir .:. qjs_tf.wasm main.js
label: Hot dog
confidence: 0.8941176470588236

Learn more

Running JavaScript in WebAssembly with WasmEdge

The WasmEdge QuickJS runtime project

• Simple JavaScript examples
• Embed JavaScript in Rust
• Native host functions in JavaScript