Swift: search for json key and edit it - json

Question

I writing because I need to search a json-key passed in a function like a string. Do you have any suggestion on how I could implement it? Once I find the key I also need to edit the value. Here there is the code I wrote until now:
JSON:
{
"JSONRoot": {
"version": 1,
"Town": {
"hour": 0,
"latitude": "",
"longitude": 0,
"latitudine": 0
},
"MeasurePoints": {
"MeasurePoint": [
{
"code": "",
"codelocation": "",
}
]
},
"Wakeup": {
"startH": 6,
"startM": 0,
"maxAttempts": 3,
"maxRetry": 10
},
"Config": {
"port": 12345,
"A": {
"writable": true,
"value": 12
},
"B": {
"writable": true,
"value": 8
},
},
"Sales": {
"Stores": {
"Store": [
{
"description": "A description",
"type": "1",
"Floors": {
"basement": true,
"number": 2
},
"Doors": {
"type": "",
"number": 7
},
"Lights": {
"number": 20
}
},
{
"description": "A description",
"type": "4",
"Floors": {
"basement": none,
"number": 1
},
"Doors": {
"type": "",
"number": 4
},
"Lights": {
"number": 8
}
}
]
}
}
}
}
Structs with codable:
// MARK: - JSONConfig
struct JsonConfig: Codable {
let jsonRoot: JSONRoot?
enum CodingKeys: String, CodingKey {
case jsonRoot = "JSONRoot"
}
}
// MARK: - JSONRoot
struct JSONRoot: Codable {
let version: Int?
let measurePoints: MeasurePoints?
let wakeup: Wakeup?
let config: Config?
let sale: Sale?
enum CodingKeys: String, CodingKey {
case version
case measurePoints = "MeasurePoints"
case wakeup = "Wakeup"
case config = "Config"
case sale = "Sale"
}
}
// MARK: - Stores
struct Stores: Codable {
let stores: [Store]?
enum CodingKeys: String, CodingKey {
case stores = "Stores"
}
}
// MARK: - Store
struct Store: Codable {
let storeDescription: String?
let type: Int?
let floors: Floors?
let doors: Doors?
let lights: Lights?
enum CodingKeys: String, CodingKey {
case storeDescription = "description"
case type
case floors = "Floors"
case doors = "Doors"
case lights = "Lights"
}
}
// MARK: - Floors
struct Floors: Codable {
let basement: Bool?
let number: Int?
}
// MARK: - Doors
struct Doors: Codable {
let type: String?
let number: Int?
}
// MARK: - Lights
struct Lights: Codable {
let number: Int?
}
// MARK: - MeasurePoints
struct MeasurePoints: Codable {
let measurePoint: [MeasurePoint]?
enum CodingKeys: String, CodingKey {
case measurePoint = "MeasurePoint"
}
}
// MARK: - MeasurePoint
struct MeasurePoint: Codable {
let code, codeLocation: String?
}
// MARK: - Config
struct Config: Codable {
let port: Int?
let a, b: K?
enum CodingKeys: String, CodingKey {
case port
case a = "A"
case b = "B"
}
}
// MARK: - K
struct K: Codable {
let writable: Bool?
let value: Int?
}
// MARK: - Wakeup
struct Wakeup: Codable {
let startH, startM, maxAttempts, maxRetry: Int?
}
Function to search for a key:
func setKeyValue(jsonKey: String, value: String) {
let decoder = JSONDecoder()
let jsonData = Data(C.jsonString.utf8)
if let jsonResult = try? decoder.decode(JsonConfig.self, from: jsonData) {
// At this point I have the jsonKey = "JSONRoot.Wakeup.maxRetry" but how I can use it to search for
// the key in the jsonResult?
}
}
Obviously I need to create a new struct to edit the json but one step at a time.

Answer 1

Using JSONSerialisation is probably the most straightforward way here
var value: Any?
do {
if let jsonResult = try JSONSerialization.jsonObject(with: data) as? [String: Any] {
let keys = "JSONRoot.Wakeup.maxRetry".split(separator: ".").map {String($0)}
var dict = jsonResult
for i in 0..<keys.count {
if let temp = dict[keys[i]] as? [String:Any] {
dict = temp
continue
}
value = dict[keys[i]]
}
}
} catch {
print(error)
}
Note that this doesn't support arrays but a solution for that is very dependent on how the search key syntax would handle an array

Answer 2

If my thinking is correct as you, you can try with this code.
override func viewDidLoad() {
super.viewDidLoad()
let jsonString = """
{
"JSONRoot": {
"version": 1,
"Town": {
"hour": 0,
"latitude": "",
"longitude": 0,
"latitudine": 0
},
"MeasurePoints": {
"MeasurePoint": [{
"code": "",
"codelocation": ""
}]
},
"Wakeup": {
"startH": 6,
"startM": 0,
"maxAttempts": 3,
"maxRetry": 10
},
"Config": {
"port": 12345,
"A": {
"writable": true,
"value": 12
}
},
"Sales": {
"Stores": {
"Store": [{
"description": "A description",
"type": "1",
"Floors": {
"basement": true,
"number": 2
},
"Doors": {
"type": "",
"number": 7
},
"Lights": {
"number": 20
}
},
{
"description": "A description",
"type": "4",
"Floors": {
"basement": "none",
"number": 1
},
"Doors": {
"type": "",
"number": 4
},
"Lights": {
"number": 8
}
}
]
}
}
}
}
"""
editJson(jsonString)
}
func editJson(_ jsonString: String) {
do{
let jsonData = Data(jsonString.utf8)
var jsonObject = try JSONSerialization.jsonObject(with: jsonData)
parseDict(&jsonObject)
print("jsonObject: \(String(describing: jsonObject))")
}catch let error {
print(error.localizedDescription)
}
}
func parseDict(_ jsonObject: inout Any) {
if let _ = jsonObject as? String {
return
} else if var dictionary = jsonObject as? Dictionary<String, Any> {
for (key, value) in dictionary {
var nextObject = value
parseDict(&nextObject)
if let value = getValueWith(key), let _ = dictionary.removeValue(forKey: key) {
dictionary[key] = value
} else {
dictionary[key] = nextObject
}
}
jsonObject = dictionary
}else if let array = jsonObject as? Array<Any> {
var updatedArray = array
for (index, value) in array.enumerated() {
var nextObject = value
parseDict(&nextObject)
updatedArray[index] = nextObject
}
jsonObject = updatedArray
}
}
func getValueWith(_ key: String) -> String? {
return [
"description" : "Amit (amitpstu1#gmail.com) ... so on"
][key]
}

Answer 3

You can refresh your memory or learn more here:
https://developer.apple.com/documentation/foundation/archives_and_serialization/using_json_with_custom_types
You would be looking at merge json from different depths section. Using encodable extension etc.
You could also look here: In Swift, can one use a string to access a struct property? If you want to roll your own search function, like a modified dfs or something.