examples

Examples need to be compiled to wasm components and published to the runtime.

Prerequisites

• Rust with the wasm32-wasi and wasm32-unknown-unknown targets
• wasm-tools cli
• wasi_snapshot_preview1 adapter

Building wasi_snapshot_preview1 adapter

At the time of writing, the adapater can be compiled from the bytecodealliance/preview2-prototyping repository.

git clone https://github.com/bytecodealliance/preview2-prototyping.git
cd preview2-prototyping

The wasi_snapshot_preview1.wasm module needs to be built to the wasm32-unknown-unknown target.

cargo build --target wasm32-unknown-unknown --release

This will build a wasm file in target/wasm32-unknown-unknown/release/wasi_snapshot_preview1.wasm. This can be used as the adapater to convert the wasm module to a component with the wasm-tools cli.

Building an example

Modules need to be built to wasm32-wasi, and converted to a wasm component.

Start by building the counter example.

cargo build -p counter --release --target wasm32-wasi

Then you can use the wasm-tools cli to convert this to a wasm component using the wasi_snapshot_preview1.wasm adapter.

wasm-tools component new \
  ./target/wasm32-wasi/release/counter.wasm \
  --adapt ../../bytecodealliance/preview2-prototyping/target/wasm32-unknown-unknown/release/wasi_snapshot_preview1.wasm \
  -o ./counter.component.wasm

You should be left with a counter.component.wasm file. You can publish this to the runtime using thalo-cli.

cargo run -p thalo_cli -- --url "http://localhost:4433" publish ./examples/counter/counter.esdl ./counter.component.wasm

Once published, you can finally execute a command.

cargo run -p thalo_cli -- --url "http://localhost:4433" execute Counter counter-1 increment '{"amount":1}'