Function Components

Factory functions — #[component]

For construction logic that doesn't fit a plain struct literal (or types you don't own), write a free function instead:

use axumstart_components::{component, ComponentProvider};

#[component]
fn build_http_client() -> reqwest::Client {
    reqwest::Client::new()
}

#[component]
async fn build_thing(ctx: &ComponentProvider) -> Thing {
    let db: Arc<Database> = ctx.get().await;
    Thing::new(db)
}

Rules: at most one parameter, and it must be &ComponentProvider; the function must return the constructed type (async or sync, both work).

Like #[derive(Component)], this expands to a ComponentBlueprint impl plus an inventory registration, so it participates in register_all() automatically.