How to send body parameter in Alamofire in Swift? - json

Question

I have an api which consumes BODY parameter, like this
{"answers":[{"qid":2588,"value":["Free Society"]},{"qid":150,"value":["Closing of fSociety"]}],"uniqid":"t4815694"}
So what I have done is, I have created Data Model named SubmitAnswerModel like this which contains another Data Model named QuestionAnswersToSubmit
import Foundation
import ObjectMapper
import RealmSwift
class SubmitAnswerModel: Object {
var answers = [QuestionAnswersToSubmit]()
#objc dynamic var uniqid: String?
override static func primaryKey() -> String {
return "uniqid"
}
}
class QuestionAnswersToSubmit: Object {
#objc dynamic var qid = 0
var value = [String]()
override static func primaryKey() -> String {
return "qid"
}
}
So this object extends RealmObject and now I need to set values to this object and send it as BODY parameter in the api. I am doing it like this
func submitAnswerToApi() {
guard let token = UserDefault().getLoginAccessTokenKey() else {
print("No login token. Please relogin.")
return
}
let answersToSubmit = SubmitAnswerModel() //main model
let realm = try! Realm()
let savedExamResponse = realm.object(ofType: SavedExamResponse.self, forPrimaryKey: id)
answersToSubmit.uniqid = savedExamResponse?.uniqueId
var answerListToSubmit = [QuestionAnswersToSubmit]()
for item in (savedExamResponse?.questionAnswerList)! {
let answerToSubmit = QuestionAnswersToSubmit()
answerToSubmit.qid = item.questionId
answerToSubmit.value = [item.selectedOption]
answerListToSubmit.append(answerToSubmit)
}
answersToSubmit.answers = answerListToSubmit
let urlString = UrlCollection.submitAnswerUrl + "uniqid=" + answersToSubmit.uniqid! + "&token=" + token
let param = answersToSubmit
let uniqidParam = answersToSubmit.uniqid
dump(param)
var request = URLRequest(url: URL(string: urlString)!)
request.httpMethod = "POST"
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
if (!JSONSerialization.isValidJSONObject(answersToSubmit)) {
print("is not a valid json object")
//return
}
request.httpBody = try? JSONSerialization.data(withJSONObject: answersToSubmit)
Alamofire.request(request)
.responseJSON { response in
switch response.result {
case .failure(let error):
print(error)
if let data = response.data, let responseString = String(data: data, encoding: .utf8) {
print(responseString)
}
case .success(let responseObject):
print(responseObject)
}
}
}
So the problem now is, I am getting this error Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '*** +[NSJSONSerialization dataWithJSONObject:options:error:]: Invalid top-level type in JSON write'. What is the proper way to pass BODY parameter in SWIFT. Any help would be appreciated. Thanks!

Answer 1

Your Json format could be wrong, please refer to this question:
Invalid top-level type in JSON write'
Btw, the preferred way to set body using Alamofire is to pass a Dictionary to the parameters and then set encoding to URLEncoding.httpbody, like so:
let parameters: Parameters = ["foo": "bar"]
Alamofire.request("https://someapi/post", parameters: parameters, encoding: URLEncoding.httpbody)