How to parse json with Alamofire in Swift 5 - ios

Question

I'm new in iOS programming language and I'm trying to fetch data from a WordPress JSON into a table view. I'm encountering the error:
value of type 'Any' has no subscripts
when I try to instantiate the object of the array.
Here is the JSON:
[
{
"id": 1352,
"date": "2019-10-16T09:30:39",
"date_gmt": "2019-10-16T09:30:39",
"guid": {
"rendered": "https://wepress.comm-it.it/ddjhgtr/"
},
"modified": "2019-10-16T13:23:41",
"modified_gmt": "2019-10-16T13:23:41",
"slug": "ddjhgtr",
"status": "publish",
"type": "post",
"link": "https://wepress.comm-it.it/ddjhgtr/",
"title": "ddjhgtr",
"content": "eryyreytyvggjggvhghhh",
"excerpt": "eryyreyty",
"author": 2,
"featured_media": {
"id": 1418,
"url": "https://wepress.comm-it.it/wp-content/uploads/2019/10/10-62.jpeg"
},
"comment_status": "open",
"ping_status": "open",
"sticky": false,
"template": "",
"format": "standard",
"meta": [],
"categories": [
{
"id": 1,
"name": "Uncategorized",
"description": ""
}
],
"tags": [],
"_links": {
"self": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts/1352"
}
],
"collection": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts"
}
],
"about": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/types/post"
}
],
"author": [
{
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/users/2"
}
],
"replies": [
{
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/comments?post=1352"
}
],
"version-history": [
{
"count": 3,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts/1352/revisions"
}
],
"predecessor-version": [
{
"id": 1419,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts/1352/revisions/1419"
}
],
"wp:featuredmedia": [
{
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/media/1418"
}
],
"wp:attachment": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/media?parent=1352"
}
],
"wp:term": [
{
"taxonomy": "category",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/categories?post=1352"
},
{
"taxonomy": "post_tag",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/tags?post=1352"
},
{
"taxonomy": "difficulty-level-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/difficulty-level-course?post=1352"
},
{
"taxonomy": "category-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/category-course?post=1352"
},
{
"taxonomy": "location-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/location-course?post=1352"
},
{
"taxonomy": "duration-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/duration-course?post=1352"
}
],
"curies": [
{
"name": "wp",
"href": "https://api.w.org/{rel}",
"templated": true
}
]
}
},
....(many other News objects)
{
"id": 774,
"date": "2019-10-07T07:30:51",
"date_gmt": "2019-10-07T07:30:51",
"guid": {
"rendered": "https://wepress.comm-it.it/name-here/"
},
"modified": "2019-10-07T07:30:51",
"modified_gmt": "2019-10-07T07:30:51",
"slug": "name-here",
"status": "publish",
"type": "post",
"link": "https://wepress.comm-it.it/name-here/",
"title": "name here",
"content": "desc here",
"excerpt": "desc here",
"author": 2,
"featured_media": null,
"comment_status": "open",
"ping_status": "open",
"sticky": false,
"template": "",
"format": "standard",
"meta": [],
"categories": [
{
"id": 1,
"name": "Uncategorized",
"description": ""
}
],
"tags": [],
"_links": {
"self": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts/774"
}
],
"collection": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts"
}
],
"about": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/types/post"
}
],
"author": [
{
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/users/2"
}
],
"replies": [
{
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/comments?post=774"
}
],
"version-history": [
{
"count": 0,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/posts/774/revisions"
}
],
"wp:attachment": [
{
"href": "https://wepress.comm-it.it/wp-json/wp/v2/media?parent=774"
}
],
"wp:term": [
{
"taxonomy": "category",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/categories?post=774"
},
{
"taxonomy": "post_tag",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/tags?post=774"
},
{
"taxonomy": "difficulty-level-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/difficulty-level-course?post=774"
},
{
"taxonomy": "category-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/category-course?post=774"
},
{
"taxonomy": "location-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/location-course?post=774"
},
{
"taxonomy": "duration-course",
"embeddable": true,
"href": "https://wepress.comm-it.it/wp-json/wp/v2/duration-course?post=774"
}
],
"curies": [
{
"name": "wp",
"href": "https://api.w.org/{rel}",
"templated": true
}
]
}
}
]
For the moment I'm interested to get just the image (featured_media), title and content of these "objects" and put them into the tableView. Indeed here are the structs that I created for them:
The news represents the struct contained into the JSON array
struct News {
public var id: Int
public var title: String
public var content: String
public var image: FeaturedMedia
}
struct FeaturedMedia {
public var id: Int
public var url: String
}
Here is the UITableViewCell class:
import UIKit
class NewsTableViewCell: UITableViewCell {
#IBOutlet weak var newsImage: UIImageView!
#IBOutlet weak var newsTitle: UILabel!
#IBOutlet weak var newsContent: UILabel!
override func awakeFromNib() {
super.awakeFromNib()
}
override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
}
}
And here the UITableViewController class:
import UIKit
import Alamofire
import Alamofire_SwiftyJSON
import SwiftyJSON
class NewsTableViewController: UITableViewController {
var newsList: [News] = [News]()
func parseJsonNews() {
DispatchQueue.main.async {
Alamofire.request("link request", method: .get).responseJSON { (response) in
switch response.result {
case .success(let value):
let news = [value]
print(news) // here in console it prints correctly the json, starting with [<__NSArrayI 0x6000001a9e60 ....
for new in news {
let title = new["title"]
print(title)
}
print(newsss)
self.tableView.reloadData()
case.failure(let error):
print(error.localizedDescription)
}
})
}
}
override func viewDidLoad() {
super.viewDidLoad()
parseJsonNews()
}
// MARK: - Table view data source
override func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
override func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.newsList.count
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "newsCell", for: indexPath) as? NewsTableViewCell
// Configure the cell...
let imageUrl = URL.init(string: newsList[indexPath.row].featuredMedia.url)
cell?.newsTitle.text = self.newsList[indexPath.row].title
cell?.newsContent.text = self.newsList[indexPath.row].content
cell.newsImage.load(url: imageUrl!)
return cell!
}
}
extension UIImageView {
func load(url: URL) {
DispatchQueue.global().async { [weak self] in
if let data = try? Data(contentsOf: url) {
if let image = UIImage(data: data) {
DispatchQueue.main.async {
self?.image = image
}
}
}
}
}
}
Looking for a solution, I just found many ways to parse dictionary JSON, but in this case, it is an array so I modified the code as you read at parseJsonNews method but it doesn't work properly.
Would be grateful for any help.

Answer 1

You can decode with Codable like this:
let data = try? JSONDecoder().decode([DummyData].self, from: jsonData)
But first, all of your models must comform Codable protocol. For example:
struct DummyData: Codable {
let id: Int
let date, dateGmt: String
let modified, modifiedGmt, slug, status: String
let type: String
let link: String
let title, content, excerpt: String
let author: Int
let commentStatus, pingStatus: String
let sticky: Bool
let template, format: String
enum CodingKeys: String, CodingKey {
case id, date
case dateGmt = "date_gmt"
case modified
case modifiedGmt = "modified_gmt"
case slug, status, type, link, title, content, excerpt, author
case commentStatus = "comment_status"
case pingStatus = "ping_status"
case sticky, template, format
}
}

Answer 2

A couple of things:
The error value of type 'Any' has no subscripts, refers to your line let title = new["title"].
the response results from Alamofire in the .success enum returns a type of Any,
this is true to the whole array of data that you fetched.
The Any type in swift doesn't have any subscripts implementations (i.e: you cannot access vars inside it using the following syntax obj['MY_VAR_NAME'].
In order to access the title from your news object like so let title = new["title"], you have to first cast the objects to a dictionary, this could be done like this:
// ...
let news = [value]
print(news)
for new in news {
if let obj = new as? [String: Any] {
let title = obj["title"]
print(title)
}
}
// ...
In order to parse/use your custom structs, they must first comply to swift's Codable protocol.
/// Example show only News, but the same which be used for FeaturedMedia
struct News {
public var id: Int
public var title: String
public var content: String
public var image: FeaturedMedia?
init?(jsonString: String) {
guard let data = jsonString.data(using: .utf8) else {
return nil
}
guard let object = News(data: data) else {
return nil
}
self = object
}
init?(data: Data) {
guard let object = try? JSONDecoder().decode(News.self, from:
data) else {
return nil
}
self = object
}
// Optional, for custom key names (i.e: "image" instead of "featured_media"
private enum CodingKeys: String, CodingKey {
case id = "id"
case image = "featured_media"
// etc..
}
}
After you've done number 4, you can then init your objects like so:
// ...
let news = [value]
print(news)
for new in news {
if let obj = News(new) {
/// obj is now a News object
let title = obj.title
print(title)
}
}
// ...
if you are in pursuit for even more info (for example to init the whole array)
check out this
I hope I've cleared things up:)

Answer 3

func ComplainData() {
let semaphore = DispatchSemaphore(value: 0)
var request = URLRequest(url: URL(string: Constant.localBaseurl2 + "compID") !, timeoutInterval: Double.infinity)
request.httpMethod = "GET"
let task = URLSession.shared.dataTask(with: request) {
data,
response,
error in
if let response = response {
let nsHTTPResponse = response as!HTTPURLResponse
print(nsHTTPResponse)
}
if let error = error {
print("\(error)")
return
}
if let data = data {
DispatchQueue.main.async {
let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase //or any other Decoder\
do {
let jsonDecoder = JSONDecoder()
let memberRecord =
try jsonDecoder.decode(COMPLAINTSVC.GetComplaints.self, from: data)
print(memberRecord.message)
for detailData in memberRecord.message {
print(detailData)
}
} catch {
print(error.localizedDescription)
}
}
}
semaphore.signal()
}
task.resume()
semaphore.wait()
}