I have tried pretty much all the potential solutions on stackoverflow and so far no luck,
This is my json response:
[
"{\"id\":5,\"request_id\":\"rqst5c17fc752d44f1.15452158\",\"business_name\":\"611 Solutions\",\"business_email\":\"611thesolutions#gmail.com\",\"title\":\"123ABC - TESTING\",\"details\":\"Package is fragile, please haul with care\",\"load_description\":\"Royal Timber\",\"amount_offered\":\"2500\",\"pickup_address\":\"123 Colliumeal Dr, Fort Wayne, Indiana\",\"dropoff_address\":\"647 Airportway, Chicago, Illinois\",\"timestamp\":\"2018-12-17 19:43:49\"}"
]
Notice there are backslashes within the key and values of the json and my parsing is failing, this is how I am parse the json:
Alamofire.request(JOB_REQUEST_BASE_URL, method: .post, parameters: parameter, encoding: URLEncoding(), headers: nil).responseArray { (response: DataResponse<[JobResponseDataObject]>) in
log.debug("Fetching Job Requests...")
switch response.result {
case .success(let responseArray) :
log.debug(response.debugDescription)
log.debug("Sucessfully fetch job requests")
log.debug("Job request counts: \(responseArray.count)")
completionHandler(JobRequest.fetchJobRequest.Response(jobResponses: responseArray), nil)
case .failure(let error) :
log.debug("Fetching error: JobRequest")
log.debug(error.localizedDescription)
completionHandler(nil, .FailedToFetchEmptyJobRequests)
}
}
I have also tried fetching the pure string using .responseString and doing let json = response.result.value?.replacingOccurrences(of: "\\", with: "") and mapping it like so let jobs = Mapper<JobResponseDataObject>().map(JSONString: json!) so far no luck too. Please help
Thanks
You can try
if let str = responseArray.first as? String , let data = str.data(using:.utf8) {
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
let res = try decoder.decode(Root.self,from:data)
}
catch {
print(error)
}
}
struct Root: Codable {
let id: Int
let requestId, businessName, businessEmail, title: String
let details, loadDescription, amountOffered, pickupAddress: String
let dropoffAddress, timestamp: String
}
You don't need to remove backslashes - it's just serilized one more time, that means it needs to deserialize back.
Look at: Why json response includes backward slashes in web api response
Just make a Data object from the string item:
let data = stringItem.data(using: .utf8)
then decode normally using JSONDecoder.
Related
I'm pretty sure my model is correct based on my data, I cannot figure out why I am getting the format error?
JSON:
{
"1596193200":{
"clientref":1,
"type":"breakfast"
},
"1596200400":{
"clientref":0,
"type":"lunch"
},
"1596218400":{
"clientref":2,
"type":"dinner"
}
}
model:
struct Call: Decodable {
let clientref: Int?
let type: String?
}
edit updated question with the code for decoding the json data from the URL:
class CallService {
static let shared = CallService()
let CALLS_URL = "url.com/Calls.json"
func fetchCalls(completion: #escaping ([Call]) -> ()) {
guard let url = URL(string: CALLS_URL) else { return }
URLSession.shared.dataTask(with: url) { (data, response, error) in
// handle error
if let error = error {
print("Failed to fetch data with error: ", error.localizedDescription)
return
}
guard let data = data else {return}
do {
let call = try JSONDecoder().decode([Call].self, from: data)
completion(call)
} catch let error {
print("Failed to create JSON with error: ", error.localizedDescription)
}
}.resume()
}
}
I strongly suggest to learn how to debug: it includes where to look, what info to get, where to get them, etc, and at the end, fix it.
That's a good thing that you print the error, most beginner don't.
print("Failed to create JSON with error: ", error.localizedDescription)
=>
print("Failed to create JSON with error: ", error)
You'll get a better idea.
Second, if it failed, print the data stringified. You're supposed to have JSON, that's right. But how often do I see question about that issue, when it fact, the answer wasn't JSON at all (the API never stated it will return JSON), the author were facing an error (custom 404, etc.) and did get a XML/HTML message error etc.
So, when the parsing fails, I suggest to do:
print("Failed with data: \(String(data: data, encoding: .utf8))")
Check that the output is a valid JSON (plenty of online validators or apps that do that).
Now:
I'm pretty sure my model is correct based on my data,
Well, yes and no.
Little tip with Codable when debuting (and not using nested stuff): Do the reverse.
Make your struct Codable if it's not the case yet (I used Playgrounds)
struct Call: Codable {
let clientref: Int?
let type: String?
}
do {
let calls: [Call] = [Call(clientref: 1, type: "breakfast"),
Call(clientref: 0, type: "lunch"),
Call(clientref: 2, type: "dinner")]
let encoder = JSONEncoder()
encoder.outputFormatting = [.prettyPrinted]
let jsonData = try encoder.encode(calls)
let jsonStringified = String(data: jsonData, encoding: .utf8)
if let string = jsonStringified {
print(string)
}
} catch {
print("Got error: \(error)")
}
Output:
[
{
"clientref" : 1,
"type" : "breakfast"
},
{
"clientref" : 0,
"type" : "lunch"
},
{
"clientref" : 2,
"type" : "dinner"
}
]
It doesn't look like. I could only used an array to put various calls inside a single variable, and that's what you meant for decoding, because you wrote [Call].self, so you were expecting an array of Call. We are missing the "1596218400" parts. Wait, could it be a dictionary at top level? Yes. You can see the {} and the fact it uses "keys", not listing one after the others...
Wait, but now that we printed the full error, does it make more sense now?
typeMismatch(Swift.Array<Any>,
Swift.DecodingError.Context(codingPath: [],
debugDescription: "Expected to decode Array<Any> but found a dictionary instead.",
underlyingError: nil))
Fix:
let dictionary = try JSONDecoder().decode([String: Call].self, from: data)
completion(dictionary.values) //since I guess you only want the Call objects, not the keys with the numbers.
From the code you provided it looks like you are trying to decode an Array<Call>, but in the JSON the data is formatted as a Dictionary<String: Call>.
You should try:
let call = try JsonDecoder().decode(Dictionary<String: Call>.self, from: data)
I am using two textfields to pass login information to the PHP web service using Alamofire in the following way.
#IBAction func LoginButton(_ sender: Any) {
//getting the username and password
let parameters: Parameters=[
"Name":TextFieldUserName.text!,
"Pass":TextFieldPassword.text!
]
Alamofire.request(URL_USER_LOGIN, method: .post, parameters: parameters).responseJSON
{
response in
//printing response
print(response)
The following Json data is received on login.
[{"code":0,"message":"Check Username and Password....","userid":""}]
I want to use either "code" value (0 for false and 1 for true) or "message" value as String to put into an if - else statement for further steps. If Alamofire is not the best way to go about this, can someone please show another way. Thanks in advance for the help.
Do you need to deserialize the response from the server?
The easiest option is parsing response value as NSDictionary
if let JSON = response.result.value as? NSDictionary {
let code = JSON.value(forKey: "code") as? Int
let message = JSON.value(forKey: "message") as? String
}
You can also use the Codable protocol and the JSONDecoder to decode this response into your structure.
For example, declare struct:
struct LoginResponse: Codable {
var code: Int
var message: String
}
and decode response using JSONDecoder
let jsonDecoder = JSONDecoder()
let loginResponse = try? jsonDecoder.decode(LoginResponse.self, from: response.data)
I am developing an iOS App that fetches Trivia Questions from Open Trivia Database (API)
After reading the docs and played around with it I think that the best solution is to use base64 encoding (since it seems to be supported in Swift). I have successfully fetched the data and parsed it into structs using a JSONParser. The problem that I have to solve is how to convert the values from base64 to UTF8. (The keys are read correctly, and therefore it maps to my structs)
My first idea was to use decoder.dataDecodingStrategy = .base64, but that does not seem to have any effect at all. And I am not really sure why.
Is that the right way to do it, or should I decode it myself afterwards when the strings are read in to structs?
In short, the result of the Parsing is a struct containing a responseCode as an Int and array containing structs representing the questions with the strings that I want to convert to UTF8 as members
My code for parsing looks like this:
let urlPath = "https://opentdb.com/api.php?amount=10&encode=base64"
let apiURL = URL(string: urlPath)!
URLSession.shared.dataTask(with: apiURL) { (data, response, error) in
guard let data = data else {return}
do{
let decoder = JSONDecoder()
decoder.dataDecodingStrategy = .base64
let questionData = try decoder.decode(Response.self, from: data)
print(questionData)
}catch let err{
print("Error", err)
}
}.resume()
Base64 encoding is used for properties you declared as Data, not as Strings, like so:
struct Response: Codable {
let someBaseEncodedString: Data
var someString: String? {
get {
return String(data: someBaseEncodedString, encoding: .utf8)
}
}
}
So, for the example you are giving, all the properties that are returned as a base64 encoded string should have the Data type in your struct, and then after that decoded as strings.
As suggested by other answers, you can decode Data or Base-64 String after JSONSerialization or JSONDecoder decoded the API results.
But if you prefer to write decoding initializer, you can make it as follows:
This may not be much different from your own Response, I guess.
struct Response: Codable {
var responseCode: Int
var results: [Result]
enum CodingKeys: String, CodingKey {
case responseCode = "response_code"
case results
}
}
To prepare to write a decoding initializer for Response, I would like to use some extensions:
extension KeyedDecodingContainer {
func decodeBase64(forKey key: Key, encoding: String.Encoding) throws -> String {
guard let string = try self.decode(String.self, forKey: key).decodeBase64(encoding: encoding) else {
throw DecodingError.dataCorruptedError(forKey: key, in: self,
debugDescription: "Not a valid Base-64 representing UTF-8")
}
return string
}
func decodeBase64(forKey key: Key, encoding: String.Encoding) throws -> [String] {
var arrContainer = try self.nestedUnkeyedContainer(forKey: key)
var strings: [String] = []
while !arrContainer.isAtEnd {
guard let string = try arrContainer.decode(String.self).decodeBase64(encoding: encoding) else {
throw DecodingError.dataCorruptedError(forKey: key, in: self,
debugDescription: "Not a valid Base-64 representing UTF-8")
}
strings.append(string)
}
return strings
}
}
Using these extensions above, you can define the Result type as follows:
extension Response {
struct Result: Codable {
var category: String
var type: String
var difficulty: String
var question: String
var correctAnswer: String
var incorrectAnswers: [String]
enum CodingKeys: String, CodingKey {
case category
case type
case difficulty
case question
case correctAnswer = "correct_answer"
case incorrectAnswers = "incorrect_answers"
}
init(from decoder: Decoder) throws {
let container = try decoder.container(keyedBy: CodingKeys.self)
self.category = try container.decodeBase64(forKey: .category, encoding: .utf8)
self.type = try container.decodeBase64(forKey: .type, encoding: .utf8)
self.difficulty = try container.decodeBase64(forKey: .difficulty, encoding: .utf8)
self.question = try container.decodeBase64(forKey: .question, encoding: .utf8)
self.correctAnswer = try container.decodeBase64(forKey: .correctAnswer, encoding: .utf8)
self.incorrectAnswers = try container.decodeBase64(forKey: .incorrectAnswers, encoding: .utf8)
}
}
}
(You have not mentioned if your Response (or other name?) is defined as a nested type or not, but I think you can rename or modify it yourself.)
With all things above, you can simply decode the API response as:
do {
let decoder = JSONDecoder()
let questionData = try decoder.decode(Response.self, from: data)
print(questionData)
} catch {
print("Error", error)
}
By the way, you say I think that the best solution is to use base64 encoding (since it seems to be supported in Swift), but is that really true?
Base-64 to Data is supported in JSONDecoder, but it is not what you expect. So, using another encoding can be a better choice.
But, anyway, JSON string can represent all unicode characters using only ASCII with \uXXXX or \uHHHH\uLLLL. So, I do not understand why the API designers do not provide an option Standard JSON Encoding. If you can contact to them, please tell them to provide the option, that may simplify many client side codes.
I wanted to know the best way to parse json response of below type in Swift 4. Response is double encoded -
\"[{\\"value\\":\\"International University \\\\"MITSO\\\\"\\",\\"id\\":\\"a1v24000000uOrPAAU\\",\\"addlFields\\":[\\"Mi?narodny Universitet \\\\"MITSO\\\\"\\"]}]\"
Here is the data in NSData format -
(String) $R0 = "data: Optional(146 bytes) as NSData: <225b7b5c 2276616c 75655c22 3a5c2249 6e746572 6e617469 6f6e616c 20556e69 76657273 69747920 5c5c5c22 4d495453 4f5c5c5c 225c222c 5c226964 5c223a5c 22613176 32343030 30303030 754f7250 4141555c 222c5c22 6164646c 4669656c 64735c22 3a5b5c22 4d693f6e 61726f64 6e792055 6e697665 72736974 6574205c 5c5c224d 4954534f 5c5c5c22 5c225d7d 5d22>"
As you see value of the key "value" has a inner double quotes(").
JSONSerialization consider this as invalid Json.
Any help will be greatly appreciated.
The content of your data as String is as follows:
"[{\"value\":\"International University \\\"MITSO\\\"\",\"id\":\"a1v24000000uOrPAAU\",\"addlFields\":[\"Mi?narodny Universitet \\\"MITSO\\\"\"]}]"
Seeing the actual content without extra double-quotes and backslashes needed to show String as String-literal, it looks like some valid JSON is embedded in a String.
This may happen when the server side code double-encodes the data. You should better tell your server side engineer to fix the issue, but if it is difficult or would take long time, you can double-decode it.
Testing code:
import Foundation
let dataStr = "<225b7b5c 2276616c 75655c22 3a5c2249 6e746572 6e617469 6f6e616c 20556e69 76657273 69747920 5c5c5c22 4d495453 4f5c5c5c 225c222c 5c226964 5c223a5c 22613176 32343030 30303030 754f7250 4141555c 222c5c22 6164646c 4669656c 64735c22 3a5b5c22 4d693f6e 61726f64 6e792055 6e697665 72736974 6574205c 5c5c224d 4954534f 5c5c5c22 5c225d7d 5d22>".dropFirst().dropLast().replacingOccurrences(of: " ", with: "")
let byteArr = stride(from: 0, to: dataStr.count, by: 2).map{(index: Int)->UInt8 in
let start = dataStr.index(dataStr.startIndex, offsetBy: index)
let end = dataStr.index(start, offsetBy: 2)
return UInt8(dataStr[start..<end], radix: 16)!
}
let responseData = Data(bytes: byteArr)
print(responseData as NSData)
Check here, whether the print statement output is exactly the same as your sample response. (If you want to test the following code with your actual data than sample response, use just let responseData = result as! Data instead of above lines.)
So, you just need to use JSONSerialization twice:
block: do {
let firstDecoded = try JSONSerialization.jsonObject(with: responseData, options: .allowFragments) as! String
let firstDecodedData = firstDecoded.data(using: .utf8)!
let secondDecoded = try JSONSerialization.jsonObject(with: firstDecodedData)
//Code below is an example of using decoded result.
guard let resultArray = secondDecoded as? [[String: Any]] else {
print("result is not an Array of Dictionary")
break block
}
print(resultArray)
if
let addlFields = resultArray[0]["addlFields"] as? [String],
let firstAddl = addlFields.first
{
print(firstAddl)
}
} catch {
print(error)
}
Outputs: (Omitting some output for print(responseData as NSData).)
[["id": a1v24000000uOrPAAU, "value": International University "MITSO", "addlFields": <__NSSingleObjectArrayI 0x100e40c80>(
Mi?narodny Universitet "MITSO"
)
]]
Mi?narodny Universitet "MITSO"
(You may find some parts like <__NSSingleObjectArrayI 0x100e40c80> are strange, but it's just a problem of generating default description and you can access the elements as an Array.)
Anyway, please try and see what you can get with my code above.
#OOPer thank you for the solution. Appreciate you giving your time.
Solution worked as expected. Pasting code here which may help others.
Here is how I am doing -
func getData(text:String, callback:#escaping (_ result: Array<somedata>?,_ error:Error?) -> Void) {
let params = ["search":text]
getDataSomeAPI(url: "http:\\xyz.com\fdf", params: params) { (result, error) in
if error == nil {
do {
//Response is double encoded
if let firstDecoded = try JSONSerialization.jsonObject(with: result as! Data, options: .allowFragments) as? String
{
let firstDecodedData = firstDecoded.data(using: .utf8)!
if let secondDecoded = try JSONSerialization.jsonObject(with: firstDecodedData) as? NSArray {
var array = [somedata]()
for obj in secondDecoded {
Mapper<somedata>().map(JSONObject: obj).then { mappedObj in
array.append(mappedObj)
}
}
callback(array,nil)
}
}
}
catch {
//Handle unexpected data format
let error = NSError(domain: "",
code: 0,
userInfo: nil)
let sErr = Error(err: error)
callback(nil, sErr)
}
} else {
callback(nil, error)
}
}
}
I have a JSON array created using this call:
guard let json = (try? JSONSerialization.jsonObject(with: content, options: JSONSerialization.ReadingOptions.mutableContainers)) as? [Any] else {
print("This is not JSON!!!")
return
}
I am trying to get elements from the JSON objects in the array to display them using the following code:
struct sWidget: Codable{
var createdBy: String
var createdDate: Date
var status: String
var widgetNumber: String
var updatedBy: String
var updatedDate: Date
}
do {
let decoder = JSONDecoder()
for (index, value) in json.enumerated() {
let currentWidget = try decoder.decode(sWidget.self, from: json[index] as! Data)
let currentNum = currentWidget.widgetNumber
//print(currentNum)
widgetNums.append(currentNum)
}
}
catch {
print("decoding error")
}
The code compiles but when I run it I get this error in the output:
Could not cast value of type '__NSDictionaryM' (0x1063c34f8) to
'NSData' (0x1063c1090). 2018-08-09 09:41:02.666713-0500
TruckMeterLogScanner[14259:1223764] Could not cast value of type
'__NSDictionaryM' (0x1063c34f8) to 'NSData' (0x1063c1090).
I am still investigating but any tips would be helpful.
Did you try that fetching objects like above mentioned? Because i see that you are using Codable. Fetching is very simple with that actually.
let yourObjectArray = JSONDecoder().decode([sWidget].self, data: json as! Data)
May be this line can be buggy but you can fetch them with one line.
Extending #Cemal BAYRI's answer:
JSONDecoder() throws, so make sure to either us try? or try (don't forget do-catch with try)
guard let data = content as? Data else {
return [sWidget]()
}
let jsonDecoder = JSONDecoder()
1. try?
let yourObjectArray = try? jsonDecoder.decode([sWidget].self, data: data)
2. try
do {
let yourObjectArray = try jsonDecoder.decode([sWidget].self, data: data)
} catch let error {
}
Note: You would need to take care of Data and Date formatting. Below is an example for Date:
jsonDecoder.dateDecodingStrategy = .iso8601
You can also check it out here