I have the following code that makes an API request to a flurry.com API endpoint and decodes the request.
let url = URL(string: bookStarRateDomainUrl)!
let task = URLSession.shared.dataTask(with: url, completionHandler: { (data, response, error) in
if let error = error {
print("Error with fetching book star rates: \(error)")
return
}
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode) else {
print("Error with the response, unexpected status code: \(response)")
return
}
if let data = data,
let flurryItems = try? JSONDecoder().decode(FlurryItem.self, from: data) {
completionHandler(flurryItems.results ?? [])
}
})
task.resume()
The problem is that I cannot use .decode(FlurryItem.self, because the values I get back from the API endpoint is this:
[{
dateTime:2020-06-05 00:00:00.000-07:00
event|name:BookStarRate
paramName|name:bookId
paramValue|name:why-buddism-is-true
count:3
}]
notice how the variable name is "paramName|name". The | makes it impossible to name a variable for that item. What can I do instead?
1- You need to use enum
struct Root: Codable {
var date: String
var name: String
var id: Int
var value: String
var count: Int
enum CodingKeys: String, CodingKey {
case date = "dateTime"
case name = "event|name"
case id = "paramName|name"
case value = "paramValue|name"
case count
}
}
2- You should use [FlurryItem].self
let flurryItems = try? JSONDecoder().decode([FlurryItem].self, from: data)
Related
I am a beginner in iOS development. I was trying to use an api URl: https://www.arbeitnow.com/api/job-board-api in my job search iOS app. But nothing shows on my app. I tested the URL in POSTMAN and it returns json(but HTML in description part?). I wrote the code:
func getResults(completed: #escaping (Result<[Results], ErrorMessage>) -> Void) {
let urlString = "https://www.arbeitnow.com/api/job-board-api"
guard let url = URL(string: urlString) else {return}
let task = URLSession.shared.dataTask(with: url) { data, response, error in
if let _ = error {
completed(.failure(.invalidData))
return
}
guard let response = response as? HTTPURLResponse, response.statusCode == 200 else {
completed(.failure(.invalidResponse))
return
}
guard let data = data else {
completed(.failure(.invalidData))
return
}
do {
let deconder = JSONDecoder()
deconder.keyDecodingStrategy = .convertFromSnakeCase
let results = try deconder.decode([Results].self, from: data)
completed(.success(results))
} catch {
completed(.failure(.invalidData))
}
}
task.resume()
}
struct Results: Codable {
let slug, companyName, title, resultsDescription: String
let remote: Bool
let url: String
let tags, jobTypes: [String]
let location: String
let createdAt: Int
enum CodingKeys: String, CodingKey {
case slug
case companyName = "company_name"
case title
case resultsDescription = "description"
case remote, url, tags
case jobTypes = "job_types"
case location
case createdAt = "created_at"
}
}
I used the code in HomeViewController:
override func viewDidLoad() {
super.viewDidLoad()
title = "Home"
collectionView.backgroundColor = UIColor(named: "backgroundMain")
collectionView.register(SearchViewCell.self, forCellWithReuseIdentifier: cellId)
setupSearchBar()
Service.shared.getResults() { [weak self] result in
switch result {
case .success(let results):
print(results)
self?.jobResults = results
DispatchQueue.main.async {
self?.collectionView.reloadData()
}
case .failure(let error):
print(error)
}
}
}
888
I don't know what is wrong with my code. Can anyone help? Thanks!
You are discarding all meaningful error information, which will make this hard to diagnose. If you get an Error object, you should return that:
enum WebServiceError: Error {
case httpError(Data, Int)
}
func getResults(completion: #escaping (Result<[Results], Error>) -> Void) {
let urlString = "https://www.arbeitnow.com/api/job-board-api"
guard let url = URL(string: urlString) else {
completion(.failure(URLError(.badURL)))
return
}
let task = URLSession.shared.dataTask(with: url) { data, response, error in
guard
let data = data,
let response = response as? HTTPURLResponse,
error == nil
else {
completion(.failure(error ?? URLError(.badServerResponse)))
return
}
guard 200 ..< 300 ~= response.statusCode else {
completion(.failure(WebServiceError.httpError(data, response.statusCode)))
return
}
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
let results = try decoder.decode([Results].self, from: data)
completion(.success(results.data))
} catch {
completion(.failure(error))
}
}
task.resume()
}
So, that will,
if there was a URLSession error, tell you what the error was;
if there was a non-2xx status code, tell you what the code was (and return the body of the response, too, in case you want to look at that); and
if there was a parsing error, tell you what the parsing error was.
Without something like this, that captures the salient error information, you are flying blind.
In this case, the error is that you are parsing for [Results], but the structure is a dictionary, whose key is data and whose value is a [Results]. You are missing an object for this dictionary that wraps the [Results].
struct ResponseObject: Decodable {
let data: [Posting]
let links: Links
let meta: Meta
}
struct Posting: Decodable {
let slug, companyName, title, description: String
let remote: Bool
let url: String
let tags, jobTypes: [String]
let location: String
let createdAt: Int
}
struct Links: Decodable {
let first: URL?
let last: URL?
let prev: URL?
let next: URL?
}
struct Meta: Decodable {
let currentPage: Int
let path: URL
let perPage: Int
let from: Int
let to: Int
let terms: String
let info: String
}
func getResults(completion: #escaping (Result<[Posting], Error>) -> Void) {
let urlString = "https://www.arbeitnow.com/api/job-board-api"
guard let url = URL(string: urlString) else {
completion(.failure(URLError(.badURL)))
return
}
let task = URLSession.shared.dataTask(with: url) { data, response, error in
guard
let data = data,
let response = response as? HTTPURLResponse,
error == nil
else {
completion(.failure(error ?? URLError(.badServerResponse)))
return
}
guard 200 ..< 300 ~= response.statusCode else {
completion(.failure(WebServiceError.httpError(data, response.statusCode)))
return
}
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
let results = try decoder.decode(ResponseObject.self, from: data)
completion(.success(results.data))
} catch {
completion(.failure(error))
}
}
task.resume()
}
Your model does not match the JSON you receive from the link you provided:
Using:
struct Root: Codable{
let data: [WorkData]
let links: Links
let meta: Meta
}
// MARK: - Links
struct Links: Codable {
let first: String
let last, prev: String?
let next: String
}
// MARK: - Meta
struct Meta: Codable {
let currentPage, from: Int
let path: String
let perPage, to: Int
let terms, info: String
enum CodingKeys: String, CodingKey {
case currentPage = "current_page"
case from, path
case perPage = "per_page"
case to, terms, info
}
}
struct WorkData: Codable {
let slug, companyName, title, payloadDescription: String
let remote: Bool
let url: String
let tags, jobTypes: [String]
let location: String
let createdAt: Int
enum CodingKeys: String, CodingKey {
case slug
case companyName = "company_name"
case title
case payloadDescription = "description"
case remote, url, tags
case jobTypes = "job_types"
case location
case createdAt = "created_at"
}
}
should solve the problem
Usage:
let root = JsonDecoder().decode(Root.self, from: data)
let firstCompany = root.data[0]
Edit to adress the comment:
This should work!
let results = try decoder.decode([Results].self, from: data)
is your code isn´t it?
instead use:
let root = JsonDecoder().decode(Root.self, from: data)
how could data be missing here?
After that you should either map the root object to your Result type to keep your Viewmodel and completion Handler the way they are now. Or change Viewmodel and completion Handler instead.
i have this struct import Foundation
import Foundation
// MARK: - Welcome
struct Say: Codable {
let response: [Rest]
init(response: [Rest]) {
self.response = response
}
}
// MARK: - Response
struct Rest: Codable {
let eventID: String
let data: ClassMe
enum CodingKeys: String, CodingKey {
case eventID = "event_id"
case data
}
init(eventID: String, data: ClassMe) {
self.eventID = eventID
self.data = data
}
}
// MARK: - DataClass
struct ClassMe: Codable {
let toTime, to, addInfo, maxWeight: String
let freeSpace, type, fromTime: String
let blocked: Blocked
let fromDate: String
let index: Int
let toDate, cost, from: String
let isDeleted: Bool
let userID: String
enum CodingKeys: String, CodingKey {
case toTime, to, addInfo, maxWeight, freeSpace, type, blocked, fromTime, fromDate, index
case toDate = "ToDate"
case cost, from
case isDeleted = "is_deleted"
case userID = "userId"
}
init(toTime: String, to: String, addInfo: String, maxWeight: String, freeSpace: String, type: String, blocked: Blocked, fromTime: String, fromDate: String, index: Int, toDate: String, cost: String, from: String, isDeleted: Bool, userID: String) {
self.toTime = toTime
self.to= to
self.addInfo = addInfo
self.maxWeight = maxWeight
self.freeSpace = freeSpace
self.type = type
self.blocked = blocked
self.fromTime = fromTime
self.fromDate = fromDate
self.index = index
self.toDate = toDate
self.cost = cost
self.from = from
self.isDeleted = isDeleted
self.userID = userID
}
}
enum Blocked: Codable {
case anythingArray([JSONAny])
case string(String)
init(from decoder: Decoder) throws {
let container = try decoder.singleValueContainer()
if let x = try? container.decode([JSONAny].self) {
self = .anythingArray(x)
return
}
if let x = try? container.decode(String.self) {
self = .string(x)
eturn
}
throw DecodingError.typeMismatch(Blocked.self, DecodingError.Context(codingPath: decoder.codingPath, debugDescription: "Wrong type for Blocked"))
}
func encode(to encoder: Encoder) throws {
var container = encoder.singleValueContainer()
switch self {
case .anythingArray(let x):
try container.encode(x)
case .string(let x):
try container.encode(x)
}
}
}
and if i want to save in core inside an http request i can’t for i
func httpfetchEventFly(){
// declare the parameter as a dictionary that contains string as key and value combination. considering inputs are valid
let dateFormatter = DateFormatter()
let t: [Int] = Array(0...100)
// var i: Int = 0
#State var i = 0
let parameters:Dictionary<String, Any> = [
"data" : [
"date":"07-03-2022",
"type":"airplane"
]
]
// create the url with URL
let url = URL(string: "myURL")! // change server url accordingly
// create the session object
let session = URLSession.shared
// now create the URLRequest object using the url object
var request = URLRequest(url: url)
request.httpMethod = "POST" //set http method as POST
request.httpBody = parameters.percentEncoded()
// add headers for the request
request.addValue("application/json; charset=utf-8", forHTTPHeaderField: "Content-Type") // change as per server requirements
request.addValue("application/json; charset=utf-8", forHTTPHeaderField: "Accept")
do {
// convert parameters to Data and assign dictionary to httpBody of request
request.httpBody = try JSONSerialization.data(withJSONObject: parameters, options: .prettyPrinted)
} catch let error {
print(error.localizedDescription)
return
}
// create dataTask using the session object to send data to the server
let task = session.dataTask(with: request) { data, response, error in
if let error = error {
print("Post Request Error: \(error.localizedDescription)")
return
}
// ensure there is valid response code returned from this HTTP response
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode)
else {
print("Invalid Response received from the server")
return
}
// ensure there is data returned
guard let responseData = data else {
print("nil Data received from the server")
return
}
do {
// create json object from data or use JSONDecoder to convert to Model stuct
if let jsonResponse = try JSONSerialization.jsonObject(with: responseData, options: .mutableContainers) as? Dictionary<String,Any>{
print(jsonResponse)
let decoder = JSONDecoder()
do {
let loginResponse = try decoder.decode(Say.self, from: responseData)
for i in t.prefix(120) { ← ((((that doesn’t work i want a solution for the index i))))
print("fromdate:", loginResponse.response[i].data.fromDate)
let peerfly = Peerfly(context: self.persistentContainer.viewContext)
//peertraffic.fromDate = dateFormatter.date(from: loginResponse.response[i].data.fromDate)
peerfly.fromDate = loginResponse.response[i].data.fromDate
peerfly.toDate = loginResponse.response[i].data.toDate
peerfly.freeSpace = loginResponse.response[i].data.freeSpace
peerfly.from = loginResponse.response[i].data.from
peerfly.to = loginResponse.response[i].data.to
peerfly.fromTime = loginResponse.response[i].data.fromTime
peerfly.toTime = loginResponse.response[i].data.fromTime
peerfly.cost = loginResponse.response[i].data.cost
peerfly.maxWeight = loginResponse.response[i].data.maxWeight
peerfly.addInfo = loginResponse.response[i].data.addInfo
peerfly.eventID = loginResponse.response[i].eventID
}
do {
try self.persistentContainer.viewContext.save()
} catch {
print("Failed to save event \(error)")
}
DispatchQueue.main.async {
self.events = loginResponse
}
} catch {
print(error)
}
// handle json response
} else {
print("data maybe corrupted or in wrong format")
throw URLError(.badServerResponse)
}
} catch let error {
print(error.localizedDescription)
}
}
// perform the task
task.resume()
}
}
}
i want an index to loop but when it reaches a null value it doesn’t do fatal error ,and out of range , i just want to take the index that has data which is the response array and if is null it does nothing ( neither prints or throw fatal error ), but can't do it
knowing that i used persistent because i am storing in core data
thank you very much my friends
I'm making an api request:
var urlRaw = bookSummaryReadsDomainUrl + apiKey;
let url = URL(string: urlRaw.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)!)
let task = URLSession.shared.dataTask(with: url!, completionHandler: { (data, response, error) in
if let error = error {
print("Error with fetching book summary reads: \(error)")
return
}
guard let httpResponse = response as? HTTPURLResponse,
(200...299).contains(httpResponse.statusCode) else {
print("Error with the response, unexpected status code: \(response)")
return
}
if let data = data,
let flurryItems = try? JSONDecoder().decode(FlurrySummary.self, from: data) {
completionHandler(flurryItems.rows ?? [])
}
})
task.resume()
to an endpoint that returns the following data
{
"rows": [
{
"dateTime": "2020-07-04 00:00:00.000-07:00",
"event|name": "BookSummaryRead",
"paramName|name": "bookId",
"paramValue|name": "elon-musk",
"count": 12
},
...
]
import Foundation
struct FlurrySummary: Codable {
var rows: [FlurryItem]?
enum CodingKeys: String, CodingKey {
case rows = "rows"
}
}
struct FlurryItem: Codable {
var name: String?
var event: String?
var value: String?
var count: String?
var date: String?
enum CodingKeys: String, CodingKey {
case name = "paramName|name"
case event = "event|name"
case value = "paramValue|name"
case count = "count"
case date = "dateTime"
}
}
For some reason the JSONDecoder.decode part is not working. It's not filling up the flurryItems and flurryItems.rows = nil. What am I doing wrong?
The property count in FlurryItem has to be of type Int.
var count: Int?
You have to catch the Error that are thrown.
do {
if let data = data,
let flurryItems = try JSONDecoder().decode(FlurrySummary.self, from: data) {
completionHandler(flurryItems.rows ?? [])
}
} catch { print(error) }
Also, you don't need the CodingKeys in FlurrySummary since the property name is the same.
struct FlurrySummary: Codable {
var rows: [FlurryItem]?
}
Note: Also, avoid using optional declaration if the property never becomes null.
My problem:
I use the site API - https://www.themealdb.com/api.php .
I want to get a list of all products. For this purpose, the link is https://www.themealdb.com/api/json/v1/1/categories.php
In my code, I created a structure:
struct Category: Decodable {
var idCategory: Int?
var strCategory: String?
var strCategoryDescription: String?
var strCategoryThumb: String?
}
Then I try to get to the address and get the data. I can convert the incoming data to JSON. It works.
Next, I want to convert the data and write it into an array of structures.
func load(url: String, completion: #escaping (_ objects: [Category])->()) {
guard let url = URL(string: url) else { return }
let session = URLSession.shared
session.dataTask(with: url) { (data, response, error) in
guard let data = data else { return }
do {
//let json = try? JSONSerialization.jsonObject(with: data, options: [])
//print("JSONSerialization" + "\(json)")
let object = try JSONDecoder().decode([Category].self, from: data)
print("JSONDecoder" + "\(object)")
completion(object)
} catch {
print(error.localizedDescription)
}
}.resume()
}
But in this line I get an error in the console:
The data couldn’t be read because it isn’t in the correct format.
Probably a mistake in my structure. I can not deal with this problem.
There are two mistakes.
The actual error
Type 'Array' mismatch: Expected to decode Array but found a dictionary instead.
indicates that you are ignoring the root object, the dictionary with key categories
The value for key id is String not Int, note the double quotes in the JSON
Declare all struct members as non-optional constants as the JSON provides all keys the in dictionaries. And please map the horrible dictionary keys to more meaningful member names.
And print all errors and never .localizedDescription in a Decodable catch block.
struct Response: Decodable {
let categories: [Category]
}
struct Category: Decodable {
let id: String
let name: String
let description: String
let thumbnailURL: URL
private enum CodingKeys: String, CodingKey {
case id = "idCategory"
case name = "strCategory"
case description = "strCategoryDescription"
case thumbnailURL = "strCategoryThumb"
}
}
func load(url: String, completion: #escaping ([Category]) -> Void) {
guard let url = URL(string: url) else { return }
let session = URLSession.shared
session.dataTask(with: url) { (data, _, error) in
if let error = error { print(error); return }
do {
let response = try JSONDecoder().decode(Response.self, from: data!)
print("JSONDecoder", response)
completion(response.categories)
} catch {
print(error)
completion([])
}
}.resume()
}
You need two codables
struct MyData: Codable {
var categories: [Category]?
}
And
let object = try JSONDecoder().decode(MyData.self, from: data)
With a wrapper class you can fetch your categories. The following code works fine in Playground:
let json = """
{
"categories": [
{"idCategory": "1"},
{"idCategory": "2"}
]
}
"""
struct CategoryHolder: Codable {
var categories: [Category]
}
struct Category: Codable {
let idCategory: String?
let strCategory: String?
let strCategoryDescription: String?
let strCategoryThumb: String?
}
let jsonData = Data(json.utf8)
let categories = try JSONDecoder().decode(CategoryHolder.self, from: jsonData).categories
I'm trying to parse JSON response using Codable but it gives me error.
I tried to refer from the below stack overflow link but did not work.
how do I parse Any in dictionary using swift
Below is my code, not sure where I'm wrong in this.
> enum JSONError: String,Error {
> case NoData = "ERROR: no data"
> case ConversionFailed = "ERROR: conversion from JSON failed"
> }
struct Owner : Decodable {
let full_name : String
let html_url:String
let follower:follower
}
struct follower : Decodable {
let followers_url : String
}
func jsonParser() {
let urlPath = "https://api.github.com/search/repositories?q=language:ruby&sort=stars&order=desc"
guard let endpoint = NSURL(string: urlPath) else {
print("Error creating endpoint")
return
}
let request = NSMutableURLRequest(url:endpoint as URL)
URLSession.shared.dataTask(with: request as URLRequest) { (data, response, error) in
do {
guard let data = data else {
throw JSONError.NoData
}
let jsonResponse = try JSONSerialization.jsonObject(with:
data)
let entries = try! JSONDecoder().decode([Owner].self, from: jsonResponse as! Data)
print(jsonResponse)
} catch let error as JSONError {
print(error.rawValue)
} catch let error as NSError {
print(error.debugDescription)
}
}.resume()
}
I need to get 3 information from this response - full name, html url and followers.
Link for web api
https://api.github.com/search/repositories?q=language:ruby
Please latest have a look at the code.
Below is the error message :
'__NSDictionaryI' (0x102965a98) to 'NSData' (0x102964580). 2019-02-09
16:17:42.062971+0530 PhotoViewwer[13342:259997] Could not cast value
of type '__NSDictionaryI' (0x102965a98) to 'NSData' (0x102964580).
Thanks
Please learn to read JSON. It's pretty easy. There are only two collection types, array ([]) and dictionary ({})
Your structs are wrong.
In the root dictionary of the JSON there is an array of dictionaries for key items.
In each dictionary there are keys full_name and owner (here is the location of the Owner struct).
A dictionary for key follower does not exist.
These structs represent the JSON correctly
struct Response : Decodable {
let items : [Item]
}
struct Item : Decodable {
let fullName : String
let owner : Owner
}
struct Owner : Decodable {
let htmlUrl : URL // URL strings can be decoded directly into URL
let followersUrl : URL
}
Add a completion handler to your function and use an enum as result type. The failure case returns all real errors. An URLRequest is redundant. Just pass the URL. The JSONSerialization line is pointless.
The convertFromSnakeCase strategy converts snake_cased keys to camelCased struct members
enum Result {
case success(Response), failure(Error)
}
func jsonParser(completion: #escaping (Result) -> Void) {
let endpoint = URL(string:"https://api.github.com/search/repositories?q=language:ruby&sort=stars&order=desc")!
URLSession.shared.dataTask(with: endpoint) { (data, response, error) in
if let error = error { completion(.failure(error)); return }
do {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
let entries = try decoder.decode(Response.self, from: data!)
completion(.success(entries))
} catch {
completion(.failure(error))
}
}.resume()
}
And call it
jsonParser { result in
switch result {
case .success(let entries) : print(entries)
case .failure(let error) : print(error)
}
}
Basically never use NS... classes if there are native equivalents, here URL for NSURL and URLRequest for NS(Mutable)URLRequest
Edit:
In Swift 5 the syntax becomes more convenient using the native Result type. It is able to convert the throwing expression
enum Result {
case success(Response), failure(Error)
}
func jsonParser(completion: #escaping (Result<Response,Error>) -> Void) {
let endpoint = URL(string:"https://api.github.com/search/repositories?q=language:ruby&sort=stars&order=desc")!
URLSession.shared.dataTask(with: endpoint) { (data, response, error) in
if let error = error { completion(.failure(error)); return }
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
completion(Result{ try decoder.decode(Response.self, from: data!) })
}.resume()
}
You need
func jsonParser() {
let urlPath = "https://api.github.com/search/repositories?q=language:ruby&sort=stars&order=desc"
guard let endpoint = NSURL(string: urlPath) else {
print("Error creating endpoint")
return
}
let request = NSMutableURLRequest(url:endpoint as URL)
URLSession.shared.dataTask(with: request as URLRequest) { (data, response, error) in
do {
let dec = JSONDecoder()
dec.keyDecodingStrategy = .convertFromSnakeCase
let entries = try dec.decode(Root.self, from:data!)
print(entries)
} catch {
print(error)
}
}.resume()
}
struct Root : Decodable {
let items:[Item]
}
struct Owner: Codable {
let login: String
let id: Int
let nodeId: String
let avatarUrl: String
let gravatarId: String
let url, htmlUrl, followersUrl: String
let followingUrl, gistsUrl, starredUrl: String
let subscriptionsUrl, organizationsUrl, reposUrl: String
let eventsUrl: String
}
struct Item: Codable {
let fullName : String
let htmlUrl:String
let owner: Owner
}
You shouldn't cast the response to data here
from: jsonResponse as! Data)
as it will crash