Relay Compiler Playground

Compile parts of the Rust Relay compiler to Wasm and expose them as a web-based playground.

Build The Wasm Module

To build the wasm module:

cd relay-compiler-playground
wasm-pack build --target web

I had to do rustup component add rust-src as well.

This will create the NPM module in relay-compiler-playground/pkg.

Publishing

Bump the version in cargo.toml. This will be used for the generated package.json.

Build (see above)

Fix:

Note: Wasm-pack has a bug which has been resolved, but not yet shipped in a release which means the files array in the generated package.json file is missing an entry. You'll need to manually update that array to include "relay_compiler_playground_bg.js" before publishing:

  "files": [
    "relay_compiler_playground_bg.wasm",
    "relay_compiler_playground_bg.js",
    "relay_compiler_playground.js",
    "relay_compiler_playground.d.ts"
  ],

More info: https://github.com/rustwasm/wasm-pack/issues/837

Finally, publish: npm publish

Testing

cd relay-compiler-playground
wasm-pack build --target nodejs # NOTE: We build for node in tests and web to publish
yarn
yarn test

Manually Testing

Follow the steps above for "Build The Wasm Module".

cd relay-compiler-playground/pkg
yarn link

cd ~/fbsource/xplat/js/RKJSModules/Libraries/Relay/oss/__github__/website
yarn link relay-compiler-playground

# Launch the website in dev mode
yarn start

Navigate to http://localhost:3000/compiler-playground