Parsing a json string in swift - json

Question

I am new from Swift programming and I'm having problems with json string parsing. My json string format is as below:
{
"fileName": "test",
"display": "test",
"children": [
{
"fileName": "test2",
"display": "test2",
"children": [
{
"fileName": "test3",
"display": "test3",
"children": [
{
"fileName": "test4",
"display": "test4"
}
]
}
]
}
]
}
I want to parse this to list Dataobject with struct parent and child but until now have no success. My code is as below:
Children model:
import Foundation
public struct Children {
public let fileName: String
public let display: String
public let children: [Children]
public init(lat: String, long: String, hourData: [Children]) {
self.fileName = lat
self.display = long
self.children = hourData
}
}
extension Children: JSONDecodable {
public init(decoder: JSONDecoder) throws {
self.fileName = try decoder.decode(key: "fileName")
self.display = try decoder.decode(key: "display")
self.children = try decoder.decode(key: "children")
}
}
import Foundation
public protocol JSONDecodable {
init(decoder: JSONDecoder) throws
}
public enum JSONDecoderError: Error {
case invalidData
case keyNotFound(String)
case keyPathNotFound(String)
}
public struct JSONDecoder {
typealias JSON = [String: AnyObject]
// MARK: - Properties
private let JSONData: JSON
// MARK: - Static Methods
public static func decode<T: JSONDecodable>(data: Data) throws -> T {
let decoder = try JSONDecoder(data: data)
return try T(decoder: decoder)
}
// MARK: - Initialization
public init(data: Data) throws {
if let JSONData = try JSONSerialization.jsonObject(with: data, options: []) as? JSON {
self.JSONData = JSONData
} else {
throw JSONDecoderError.invalidData
}
}
// MARK: -
private init(JSONData: JSON) {
self.JSONData = JSONData
}
// MARK: - Public Interface
func decode<T>(key: String) throws -> T {
if key.contains(".") {
return try value(forKeyPath: key)
}
guard let value: T = try? value(forKey: key) else { throw JSONDecoderError.keyNotFound(key) }
return value
}
func decode<T: JSONDecodable>(key: String) throws -> [T] {
if key.contains(".") {
return try value(forKeyPath: key)
}
guard let value: [T] = try? value(forKey: key) else { throw JSONDecoderError.keyNotFound(key) }
return value
}
// MARK: - Private Interface
private func value<T>(forKey key: String) throws -> T {
guard let value = JSONData[key] as? T else { throw JSONDecoderError.keyNotFound(key) }
return value
}
private func value<T: JSONDecodable>(forKey key: String) throws -> [T] {
if let value = JSONData[key] as? [JSON] {
return try value.map({ (partial) -> T in
let decoder = JSONDecoder(JSONData: partial)
return try T(decoder: decoder)
})
}
throw JSONDecoderError.keyNotFound(key)
}
// MARK: -
private func value<T>(forKeyPath keyPath: String) throws -> T {
var partial = JSONData
let keys = keyPath.components(separatedBy: ".")
for i in 0..<keys.count {
if i < keys.count - 1 {
if let partialJSONData = JSONData[keys[i]] as? JSON {
partial = partialJSONData
} else {
throw JSONDecoderError.invalidData
}
} else {
return try JSONDecoder(JSONData: partial).value(forKey: keys[i])
}
}
throw JSONDecoderError.keyPathNotFound(keyPath)
}
private func value<T: JSONDecodable>(forKeyPath keyPath: String) throws -> [T] {
var partial = JSONData
let keys = keyPath.components(separatedBy: ".")
for i in 0..<keys.count {
if i < keys.count - 1 {
if let partialJSONData = JSONData[keys[i]] as? JSON {
partial = partialJSONData
} else {
throw JSONDecoderError.invalidData
}
} else {
return try JSONDecoder(JSONData: partial).value(forKey: keys[i])
}
}
throw JSONDecoderError.keyPathNotFound(keyPath)
}
}
Please help me resolve this.