Config Components

Config components — #[derive(ComponentConfig)]

A config struct whose fields are read from environment variables once at registration time.

use axumstart_components::ComponentConfig;

#[derive(Clone, ComponentConfig)]
struct AppConfig {
    #[env_var("DATABASE_URL")]
    database_url: String,
    #[env_var("PORT", 8080)]
    port: u16,
}

#[env_var("VAR")] panics at resolution time if the variable is unset or fails to parse. #[env_var("VAR", default)] falls back to default (any expression of the field's type) if the variable is unset, but still panics on a parse failure.