readme.md

wasi-component-model

Pre-Req

Install python modules - componentize-py, wasmtime-py and Runtime - wasmtime

Steps

1. Create the WIT world you'd like. Below is simple hello.wit that would print some string when hello function is called

package example:hello;
world hello {
  export hello: func() -> string;
}

2. To understand the internal bindings, you can always run below and create the GUEST; (Optional)

componentize-py -d hello.wit -w hello bindings hello_guest

3. Create the module in python and save it with name of the app.py (ACTUAL APP)

import hello
class Hello(hello.Hello):
    def hello(self) -> str:
        return "Hello, World!"

4. Generate the component app.wasm with below command from hello.wit and the module that was created above app.py

componentize-py -d hello.wit -w hello componentize --stub-wasi app -o app.wasm

or

componentize-py -d hello.wit -w hello componentize app -o app.wasm 

5. Create the host-side bindings for the component app.wasm

python3 -m wasmtime.bindgen app.wasm --out-dir hello_host

6. Now, we can write a simple host app using those bindings:

from hello_host import Root
from wasmtime import Config, Engine, Store

config = Config()
config.cache = True
engine = Engine(config)
store = Store(engine)
hello = Root(store)
print(f"component says: {hello.hello(store)}")

Flow chart :

Reference :

1. Above example
2. Implement host application in other languages - Rust, Golang, Python