wasmjs (QuickJS-NG in WebAssembly in Python)

[nmlorg]

Hi! I'm brand new to Wasm, Wasmtime, and QuickJS-NG. I wrote a Python wrapper around qjs-wasi-reactor.wasm.

$ git clone https://github.com/nmlorg/wasmjs
$ cd wasmjs
$ source ./activate
$ pytest
$ wasmjs
>>> 1 + 2
3
>>> ({hello: 1})
{'hello': 1}
>>> function mult(a, b) { return a * b; }; mult(2, 3);
6
>>> ^D
$ python
>>> from wasmjs import wasmjs
>>> js = wasmjs.WasmJS()
>>> js.eval('1 + 2')
3
>>> js.eval('({hello: 1})')
{'hello': 1}

---

1. Am I stepping on anyone's toes? Is there any reason I shouldn't be pursuing this?

2. It looks like go-quickjs-wasi-reactor and js-quickjs-wasi-reactor have qjs-wasi-reactor.wasm checked back into their own source trees, and presumably included in their packages as data. I can do that too, or I can have my package download the .wasm from GitHub as part of its installation (or first use), or I could potentially create a qjs-wasi-reactor Python package that only contains that one file (so my wasmjs code package would depend on both the wasmtime and qjs-wasi-reactor packages). Does anyone have any thoughts about this?

Thanks!

[saghul]

They there!

1. Am I stepping on anyone's toes? Is there any reason I shouldn't be pursuing this?

I don't think you are! Even if you were, nobody can tell you where to spend your time, so hack away! 💪

2. It looks like go-quickjs-wasi-reactor and js-quickjs-wasi-reactor have qjs-wasi-reactor.wasm checked back into their own source trees, and presumably included in their packages as data. I can do that too, or I can have my package download the .wasm from GitHub as part of its installation (or first use), or I could potentially create a qjs-wasi-reactor Python package that only contains that one file (so my wasmjs code package would depend on both the wasmtime and qjs-wasi-reactor packages). Does anyone have any thoughts about this?

I think it's probably best that you vendor it, or, if you are going to dynamically download it, pin it to a specific release to avoid surprises. I'd go the vendor route, to make sure your package is functional once installed, even when GH is down or whatever.

If / when you are ready to share it, we have a page with 3rd party packages here: https://quickjs-ng.github.io/quickjs/projects feel free to make a PR adding your project!

[nmlorg]

Cool 🙂

wasmjs is only 7 kB of code, and qjs-wasi-reactor.wasm is 1.5 MB, so I'd feel bad about code changes forcing people to download the .wasm over and over. I went ahead and put together a data-only package containing the .wasm file:

https://pypi.org/project/qjs-wasi-reactor.wasm/ (built from https://github.com/nmlorg/qjs-wasi-reactor.wasm)

and changed my wasmjs package to depend on that instead of expecting the file in the current directory.

If you ever want to take over ownership of this package or anything, just let me know.