✔ Importing and Calling Functions Between WASM Components · general

Here's a quick example of building two components using componentize-py, composing them, and running the result:

mkdir compose
cd compose
python3 -m venv .venv
source .venv/bin/activate
pip install componentize-py
cat >worlds.wit <<EOF
package test:test;

interface foo {
  bar: func() -> string;
}

world thing1 {
  export foo;
}

world thing2 {
  import foo;
  export run: func() -> string;
}
EOF
cat >mything1.py <<EOF
from wit_world import exports

class Foo(exports.Foo):
    def bar(self) -> string:
        return "Hello, world!"
EOF
cat >mything2.py <<EOF
import wit_world
from wit_world.imports import foo

class WitWorld(wit_world.WitWorld):
    def run(self) -> string:
        return foo.bar()
EOF
componentize-py -d worlds.wit -w thing1 componentize mything1 -o thing1.wasm
componentize-py -d worlds.wit -w thing2 componentize mything2 -o thing2.wasm
wasm-tools compose -d thing1.wasm thing2.wasm -o composed.wasm
wasmtime run --invoke 'run()' composed.wasm

Stream: general

Topic: ✔ Importing and Calling Functions Between WASM Components

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