How to decode JSON data from Alamofire request - json

I'm trying to decode the json data after fetching json with alamofire. I have created the model class but i don't understand how to decode the data.
Alamofire.request("http://somerandomlink.xyz").responseJSON { (response) in
switch response.result {
case .failure(let error):
print(error)
case .success(let data):
do {
//print(response)
print("data: \(data)")
} catch let error {
print(error)
}
}
}
Model
struct LoremIpsum: Codable {
let var1: String
let var2: String
let var3: String
}

Alamofire has been updated to use Codable objects natively.
Use:
.responseDecodable(of: LoremIpsum.self) {
Instead of:
.responseJSON {

You can also use .responseData instead of responseJSON and then in the success case you can try decoding using JSONDecoder as follows:
let decoder = JSONDecoder()
do {
let users = try decoder.decode(LoremIpsum.self, from:data)
print("Users list :", users)
} catch {
print(error)
}

guard let users = try? JSONDecoder().decode(LoremIpsum.self, from: response) else {
return
}

Related

Swift - JSON decoding

I have a JSON response from an api call. The problem is I get different JSON responses depending on whether the user has entered the correct credentials or not. My question is how do I read and decode these responses to a useable struct and what is the best way to go about decoding these different responses. one thing I noticed is both response have a common "isSuccess" that may be useful. I have little to no experience with swift or reading JSON so this is all a learning experience for me.
This is the response for successful login
{"result":{"login":{"isAuthorized":true,"isEmpty":false,"userName":{"isEmpty":false,"name":{"firstName":"Jason","lastName":"Test","displayName":"Test, Jason","isEmpty":false,"fullName":"Jason Test"},"canDelete":false,"id":5793,"canModify":false},"username":"test#testable.com"},"parameters":{"isEmpty":false,"keep_logged_in_indicator":false,"username":"test#testable.com"}},"isAuthorized":true,"version":{"major":"2021","minor":"004","fix":"04","display":"2021.004.04","isEmpty":false},"isSystemDown":false,"timestamp":"2021-07-28T02:47:33Z","isSuccess":true}
This is the response for failure
{"isAuthorized":true,"version":{"major":"2021","minor":"004","fix":"04","display":"2021.004.04","isEmpty":false},"isSystemDown":false,"errors":[{"password":"Unable to login as 'test#testable.com'"}],"timestamp":"2021-07-28T02:47:05Z","isSuccess":false}
This is the code I have written for my api calls
func request<T: Decodable>(endPoint: EndPoint, method: Method, parameters: [String: Any]? = nil, completion: #escaping(Result<T, Error>) -> Void) {
// Creates a urlRequest
guard let request = createRequest(endPoint: endPoint, method: method, parameters: parameters) else {
completion(.failure(AppError.invalidUrl))
return
}
let session = URLSession.shared
session.dataTask(with: request) { data, response, error in
var results: Result<Data, Error>?
guard let httpResponse = response as? HTTPURLResponse, httpResponse.statusCode == 200 else {
completion(.failure(AppError.badStatusCode))
return
}
if let response = response {
// Gets the JSESSIONID
let cookieName = "JSESSIONID"
if let cookie = HTTPCookieStorage.shared.cookies?.first(where: { $0.name == cookieName }) {
debugPrint("\(cookieName): \(cookie.value)")
}
print(response)
}
if let data = data {
results = .success(data)
// Converts data to readable String
let responseString = String(data: data, encoding: .utf8) ?? "unable to convert to readable String"
print("Server Response: \(responseString.description)")
} else if let error = error {
results = .failure(error)
print("Server Error: \(error.localizedDescription)")
}
DispatchQueue.main.async {
self.handleResponse(result: results, completion: completion)
}
}.resume()
}
private func handleResponse<T: Decodable>(result: Result<Data, Error>?, completion: (Result<T, Error>) -> Void) {
guard let result = result else {
completion(.failure(AppError.unknownError))
return
}
switch result {
case .success(let data):
do {
let json = try JSONSerialization.jsonObject(with: data, options: [])
print("Server JsonObject response: \(json)")
} catch {
completion(.failure(AppError.errorDecoding))
}
let decoder = JSONDecoder()
// Decodes that json data
do {
} catch {
}
case .failure(let error):
completion(.failure(error))
}
}
Im mostly interesting in being able to display the json error that occurs when credentials are incorrect. The deadline for my project Is slowing approaching and any help or suggestions would be much appreciated.
You can use Swift's Result type to differentiate a successful result from a failed result.
The Result type is not decodable by default so you will need to write a custom decoder like this:
struct Response: Decodable {
let result: Swift.Result<Result, Errors>
enum CodingKeys: String, CodingKey {
case isSuccess
case errors
case result
}
struct Result: Codable {
let login: Login
struct Login: Codable {
let isAuthorized: Bool
}
}
struct Errors: Error {
let contents: [[String: String]]
}
init(from decoder: Decoder) throws {
let container = try decoder.container(keyedBy: CodingKeys.self)
if try container.decode(Bool.self, forKey: .isSuccess) {
result = .success(try container.decode(Result.self, forKey: .result))
} else {
result = .failure(
Errors(contents: try container.decode([[String: String]].self, forKey: .errors))
)
}
}
}

SwiftJSON parsing { Key: {Key: Value} } case?

Here is my json data :
{
"whois": {
"queryType": "IPv4",
"orgID": "ORG572"
}
}
and I want to get "orgID".
I try like this :
switch response.result {
case .success(let value):
let responseJson: JSON = JSON(value)
let orgID = responseJson["whois"]["orgID"].stringValue
print(orgID)
case .failure(let error):
print(error)
}
and that 'orgID' in log console is empty.
What I have to do?
Try using Codable to parse the data instead of using a 3rd party like SwiftyJSON.
Models:
struct Response: Codable {
let whois: Whois
}
struct Whois: Codable {
let queryType, orgID: String
}
Parse the JSON data like so,
do {
let response = try JSONDecoder().decode(Response.self, from: data)
print(response.whois.orgID)
} catch {
print(error)
}

Alamofire Get Response

I get a nil in let restResponse = try? JSONDecoder().decode(SelectCourseResponse.self, from: data) any reasons ?
func getMotherLangRequest() {
showActivityIndicatory(uiView: view, show: true)
AF.request(NetworkUrl.motherLang_getRequest,
method: .get)
.responseJSON { response in
self.showActivityIndicatory(uiView: self.view, show: false)
debugPrint(response)
switch response.result {
case .success:
guard let data = response.data else { return }
let restResponse = try? JSONDecoder().decode(SelectCourseResponse.self, from: data)
if restResponse?.status == 0 {
} else { self.showErrorResponse(data: data) }
case let .failure(error): print(error)
}
}
}
here get request
My SelectCourseResponse struct
Your price, icon and update_date fields are null declare them as optional and your code will work.
I would recommend using a do/catch block and printing out the error. That said, you have a number of null fields in your JSON object but you didn't define those fields as optional in your data structures. update_date, price, and icon should all be optionals.
do {
let restResponse = try JSONDecoder().decode(
SelectCourseResponse.self,
from: data
)
process(restReponse)
} catch {
print("DECODE ERROR: \(error)")
}

How should I go about parsing a JSON response from an API with Alamofire and SwiftyJSON?

I am trying to parse a JSON from an API using Alamofire and SwiftyJSON, but am having trouble trying to access the information in the JSON. I need to simply parse the JSON for an item called "ask_price": and also "time_coinapi" but I am not sure how I manage the response, or if I have to use a different method. here is what I have at the moment:
class CoinAPIManager {
var prices: [String] = []
var times: [String] = []
static let shared = CoinAPIManager()
func getReq() {
let headers: HTTPHeaders = [
"X-CoinAPI-Key": "Key"
]
Alamofire.request("https://rest.coinapi.io/v1/quotes/BITSTAMP_SPOT_BTC_USD/history?time_start=2018-08-21T00:00:00&time_end=2018-08-22T00:00:00&limit=100", headers: headers).responseJSON { response in
debugPrint(response)
if let data = try? String(contentsOf: response) {
let json = JSON(parseJSON: data)
parse(json: json)
}
}
func parse(json: JSON) {
for result in json[].arrayValue {
let price = result["ask_price"].stringValue
}
}
}
}
and I have also tried this:
func getReq() {
let headers: HTTPHeaders = [
"X-CoinAPI-Key": "Key"
]
Alamofire.request("https://rest.coinapi.io/v1/quotes/BITSTAMP_SPOT_BTC_USD/history?time_start=2018-08-21T00:00:00&time_end=2018-08-22T00:00:00&limit=100", headers: headers).responseJSON { response in
debugPrint(response)
switch response.result {
case .failure(let error):
// Do whatever here
return
case .success(let data):
// First make sure you got back a dictionary if that's what you expect
guard let json = data as? [String : AnyObject] else {
print("Failed to get expected response from webserver.")
return
}
// Then make sure you get the actual key/value types you expect
guard var price = json["ask_price"] as? Double else {
print("Failed to get data from webserver")
return
}
}
What am I doing wrong? this is how the JSON looks:
[
{
"symbol_id": "BITSTAMP_SPOT_BTC_USD",
"time_exchange": "2013-09-28T22:40:50.0000000Z",
"time_coinapi": "2017-03-18T22:42:21.3763342Z",
"ask_price": 770.000000000,
"ask_size": 3252,
"bid_price": 760,
"bid_size": 124
},
{
"symbol_id": "BITSTAMP_SPOT_BTC_USD",
"time_exchange": "2013-09-28T22:40:50.0000000",
"time_coinapi": "2017-03-18T22:42:21.3763342",
"ask_price": 770.000000000,
"ask_size": 3252,
"bid_price": 760,
"bid_size": 124
}
]
previous question deleted and reposted due to large mistake
you need to change your response to SwiftyJSON object like this
Alamofire.request("https://rest.coinapi.io/v1/quotes/BITSTAMP_SPOT_BTC_USD/history?time_start=2018-08-21T00:00:00&time_end=2018-08-22T00:00:00&limit=100", headers: headers).responseJSON { response in
debugPrint(response)
switch response.result {
case .failure(let error):
// Do whatever here
return
case .success:
// First make sure you got back a dictionary if that's what you expect
let responseJSON = JSON(response.result.value!)
if responseJSON.count != 0 {
print(responseJSON)
//do whatever you want with your object json
}
}
}
i suggest in your ApiManager you can use completion blocks to manage asyncronous request, check the next code.
class func getRequestWithoutParams(didSuccess:#escaping (_ message: JSON) -> Void, didFail: #escaping (_ alert:UIAlertController)->Void){
Alamofire.request("http://foo.bar"),method: .post,parameters: parameters,encoding: JSONEncoding.default,headers:nil).responseJSON { response in
switch response.result{
case .success:
let res = JSON(response.result.value!)
didSuccess(res)
break
case .failure(let error):
let alert = UIAlertController(title: "Error", message: error.localizedDescription, preferredStyle: .alert)
let done = UIAlertAction(title: "OK", style: .default, handler: nil)
alert.addAction(done)
didFail(alert)
}
}
}
From Swift 4, you should be able to use codable to solve it:
struct YourStructure: Codable {
let symbol_id: String?
let time_exchange: String?
let ask_price: String?
private enum CodingKeys: String, CodingKey {
case symbol_id = "symbol_id"
case time_exchange = "time_exchange"
case ask_price = "ask_price"
}
}
And then parse it with JSONDecoder
let decoder = JSONDecoder()
let parsedData = decoder.decode(YourStructure.self, from: "YourJsonData")

Type any has no subscript members swift 3

My code is this
import UIKit
import Alamofire
class ViewController: UIViewController {
var young = "https://jsonplaceholder.typicode.com/posts"
override func viewDidLoad() {
super.viewDidLoad()
callAlamo(url: young)
}
func callAlamo(url: String){
Alamofire.request(url).responseJSON { (response) in
let responseJSON = response.data
if responseJSON == nil{
print("response is empty")
}else{
print("Jon is \(responseJSON)")
self.parseJson(JSONData: responseJSON!)
}
}
}
func parseJson(JSONData: Data){
do{
let readableJSON = try JSONSerialization.jsonObject(with: JSONData, options: .mutableContainers)
for i in 0..<(readableJSON as AnyObject).count{
print(readableJSON[i] as String)
}
}catch{
print(error)
}
}
}
I need each array element inside this Json.
Try to use below code:
Alamofire.request(url).responseJSON { (response) in
switch response.result {
case .success(let value) :
print(response.request) // original URL request
print(response.response) // HTTP URL response
print(response.data) // server data
print(response.result) // result of response serialization
if let JSON = response.result.value as! [String:AnyObject]!{
print("JSON: ",JSON)
}
case .failure(let encodingError):
completionHandler(APIResponse.init(status: "failure", response: nil, result:nil))
}
}
When using the responseJSON handler, the JSON data has already been parsed internally by JSONSerialization. You do NOT want to try to parse it again, otherwise you're parsing the server's response data twice which is really bad for performance. All you need to do is the following:
Alamofire.request(url).responseJSON { response in
if let json = response.result.value {
print("Parsed JSON: \(json)")
// Now you can cast `json` to a Dictionary or Array
}
}