#[controller("/users")]
#[derive(Default, Clone)]
struct UserController;

impl UserController {
    #[get("/:id")]
    async fn get(req: HttpRequest)
        -> Result<Json<User>, Error>
    {
        let id: u32 = req.param("id")
            .unwrap().parse().unwrap();
        let user = find_user(id).await?;
        Ok(Json(user))
    }

    #[post("")]
    async fn create(req: HttpRequest)
        -> Result<Json<User>, Error>
    {
        let dto: CreateUser = req.json()?;
        let user = create_user(dto).await?;
        Ok(Json(user))
    }
}

#[get("/users/{id}")]
async fn get_user(
    path: web::Path<u32>
) -> impl Responder {
    let id = path.into_inner();
    let user = find_user(id).await?;
    HttpResponse::Ok().json(user)
}

#[post("/users")]
async fn create_user(
    body: web::Json<CreateUser>
) -> impl Responder {
    let user = create_user(body.0).await?;
    HttpResponse::Created().json(user)
}

// In main:
App::new()
    .service(get_user)
    .service(create_user)

async fn get_user(
    Path(id): Path<u32>
) -> Result<Json<User>, AppError> {
    let user = find_user(id).await?;
    Ok(Json(user))
}

async fn create_user(
    Json(dto): Json<CreateUser>
) -> Result<Json<User>, AppError> {
    let user = create_user(dto).await?;
    Ok(Json(user))
}

// In main:
Router::new()
    .route("/users/:id", get(get_user))
    .route("/users", post(create_user))

#[get("/users/<id>")]
async fn get_user(id: u32)
    -> Result<Json<User>, Status>
{
    let user = find_user(id).await
        .map_err(|_| Status::NotFound)?;
    Ok(Json(user))
}

#[post("/users", data = "<dto>")]
async fn create_user(dto: Json<CreateUser>)
    -> Result<Json<User>, Status>
{
    let user = create_user(dto.0).await?;
    Ok(Json(user))
}

// In main:
rocket::build()
    .mount("/", routes![get_user, create_user])