just enough machinery to run in a cli

Author: pchickey

Cargo.lock

@@ -8,4 +8,7 @@ name = "component-init"
 path = "src/main.rs"
 
 [dependencies]
+anyhow.workspace = true
+clap = { version = "4", features = ["derive"] }
 component-init-wasmtime.workspace = true
+tokio = { version = "1", features = ["full"] }

cli/Cargo.toml

@@ -1,3 +1,31 @@
-fn main() {
-    println!("Hello, world!");
+use anyhow::{Context, Result};
+use clap::Parser;
+use std::path::PathBuf;
+
+/// Initialize a component. Saves the internal state of the component
+/// after its `component-init` export function has been called.
+#[derive(Parser, Debug)]
+#[command(version, about, long_about = None)]
+struct Args {
+    /// Input component.
+    #[arg(required = true)]
+    input: PathBuf,
+
+    /// Output component. If not provided, output will overwrite input.
+    #[arg(short, long)]
+    output: Option<PathBuf>,
+}
+
+#[tokio::main]
+async fn main() -> Result<()> {
+    let args = Args::parse();
+
+    let infile = &args.input;
+    let input =
+        std::fs::read(infile).with_context(|| format!("reading input from {:?}", infile))?;
+    let output = component_init_wasmtime::initialize(&input).await?;
+
+    let outfile = args.output.as_ref().unwrap_or(infile);
+    std::fs::write(outfile, output).with_context(|| format!("writing output to {:?}", outfile))?;
+    Ok(())
 }

cli/src/main.rs

@@ -4,6 +4,8 @@ version.workspace = true
 edition.workspace = true
 
 [dependencies]
+anyhow.workspace = true
+async-trait.workspace = true
 component-init.workspace = true
 wasmtime.workspace = true
 wasmtime-wasi.workspace = true