How to emit error when get json with key

Question

I'm using RxAlamorefire to handle network task in my app.

My problem is: When I make a request and it return json. If json has a key "error" I need emit error notification instead of onNext notification.

My code is like this one:

let observable = RxAlamofire.json(.get, url, parameters: nil, encoding: URLEncoding.default, headers: header)
.map { (json) -> SomeObject? in
//Should check json maybe not in ".map" to see if the json contain "error" then emit onError notification.
return Mapper<SomeObject>().map(JSONObject: json)
}

score 1 · Answer 1 · answered Apr 06 '17 at 07:33

Within map, you can use the throw keyword to send out and error

let observable = request.map { (json) -> SomeObject in
  if let error = json["error"] as? [AnyHashable: Any] {
    throw Mapper<ErrorObject>().map(JSONObject: error)
  } else {
    // regular deserialization
  }
}

This will result in an observable emitting an error of type ErrorObject when the json contains the error key.

How to emit error when get json with key

1 Answers1