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Using the Rust Host SDK

1. Install the Rust crate​

Install via Crates.io:

cargo add extism
note

If you need unreleased functionality you can install via git:

cargo add extism --git https://github.com/extism/extism.git

2. Import the library and use the APIs​

Count Vowels Plugin

code.wasm in this example is our example plugin that counts vowels. If you want to run this, download it first and set the path:

curl https://raw.githubusercontent.com/extism/extism/main/wasm/code.wasm > code.wasm
main.rs
use extism::{Context, Plugin};

fn main() {
    let wasm = include_bytes!("../../wasm/code.wasm");
    let context = Context::new();
    let mut plugin = Plugin::new(&context, wasm, false).unwrap();
    let data = plugin.call("count_vowels", "this is a test").unwrap();
    assert_eq!(data, b"{\"count\": 4}");
}

Need help?​

If you've encountered a bug or think something is missing, please open an issue on the Extism GitHub repository.

There is an active community on Discord where the project maintainers and users can help you. Come hang out!