Can Axum request bodies be inferred by the path macro?

[BrianHicks]

Hey! I see in the docs that inferring request_body is not available for all libraries, but I'm not sure how to find out which ones it's supported for. It's not working for me with Axum, but I'm not sure whether that's because it's unsupported or because I'm holding it wrong somehow. Here's what I have right now:

#[derive(ToSchema, Deserialize)]
pub struct RegisterRequest {
    email: String,
    password: String,
}

#[utoipa::path(post, path = "/api/v1/register")]
pub async fn register(
    State(_): State<Pool<Postgres>>,
    Json(_): Json<RegisterRequest>,
) -> impl IntoResponse {
    "TODO"
}

This doesn't result in any information about the request body in the generated spec. However, if I change it to this, it works:

#[utoipa::path(post, path = "/api/v1/register", request_body = RegisterRequest)]

This makes sense, to a certain extent. There are a couple reasons I'm not sure if I'm just doing something wrong, though:

• Axum seems to enforce that the body is the last parameter, which makes it seem like Utoipa should be able to see it.
• If I say request_body = Json<RegisterRequest>, compilation fails because Json<a> doesn't implement ToSchema. But maybe there's something else I need to use?