Error result of an endpoint still returns Outcome::Success

[Andynopol]

Hi! I Have an endpoint that returns the known sensors of a network switch and I am confused about the outcome.

The docs state that an Resut::Err should expect an Outcome::Erorr from the endpoint, but it's not what I am getting. I tried to use a Responder enum, but I an unsuccessful.

Here is the endpoin:

#[get("/gateway/<gateway_id>/sensors")]
async fn get_nodes(
    gateway_id: ObjectIdDto, 
    gateway_col: &State<Arc<Collection<GatewayModel>>>, 
    nodes_col: &State<Arc<Collection<NodeModel>>>, 
    registry_col: &State<Arc<Collection<RegistryModel>>>, 
    auth: Auth
) -> Result<Json<Vec<NodeDto>>, Error> {
    let gateway = match find_gateway_for_user(&gateway_col, &gateway_id.0, auth.id()).await {
        Ok(value) => value,
        Err(fail_status) => return Err(fail_status),  // Propagate error upwards
    };

    let footprints = match registry_col.distinct("digital_footprint", doc! {"gateway_key": &gateway.key}).await {
        Ok(value) => value,
        Err(_) => return Err(Error::Internal(ErrorResponse::new("Connection error",  "Unable to connect to the database cluster"))),
    };

    let mut nodes = match nodes_col.find(doc! {"gateway_key": &gateway.key, "digital_footprint": {"$in": &footprints}}).await {
        Ok(cursor) => cursor.filter_map(|result| async { match result.ok() {
            Some(value) => Some(NodeDto::from(value)),
            None => None
        }}).collect::<Vec<NodeDto>>().await,
        Err(err) => {
            error!("{:?}", err);
            return Err(Error::Internal(ErrorResponse::new("Connection error", "Unable to connect to the database cluster")));
        }
    };

    let nodes = task::spawn(async move {
        let footprints = footprints.into_iter().filter_map(|bson_value|{
            if let Bson::String(s) = bson_value {
                Some(s)
            } else {
                None
            }
        }).collect::<HashSet<String>>();

        info!("{:?}", footprints);

        let default_nodes: Vec<NodeDto> = footprints
            .into_iter()
            .filter(|fp| !gateway.known_nodes.contains(fp))
            .map(|dfp| NodeDto::from(NodeModel::new(dfp, &gateway.key, None, None)))
            .collect();

        nodes.extend(default_nodes);
        nodes
    }).await.unwrap_or_else(|e| {
        error!("Series collection failed: {:?}", e);
        vec![]
    });

    Ok(Json(nodes))  // Return a successful JSON response here
}

And here is the Erorr enum:

use rocket::{response::Responder, serde::{json::Json, Serialize}};

#[derive(Responder, Debug)]
pub enum Error {
  #[response(status = 500, content_type = "json")]
  Internal(Json<ErrorResponse>),

  #[response(status = 404, content_type = "json")]
  NotFound(Json<ErrorResponse>),

  #[response(status = 401, content_type = "json")]
  Unauthorized(Json<ErrorResponse>),

  #[response(status = 400, content_type = "json")]
  BadRequest(Json<ErrorResponse>),
}

#[derive(Serialize, Debug)]
#[serde(crate = "rocket::serde")]
pub struct ErrorResponse {
  message: String,
  error: String
}

impl ErrorResponse {
  pub fn new(error: &str, message: &str) -> Json<Self> {
    Json(Self {
      error: error.to_string(),
      message: message.to_string()
    })
  }
}

What am I doing wrong here?

[the10thWiz]

I'm not sure what docs you were reading, but according to https://rocket.rs/guide/v0.5/responses/#result, Result just delegates the response to the Ok or Err type. The reason the endpoint as a whole returns Outcome::Sucess, is because it successfully generates a response (even if that response is a 4XX or 5XX response).