Parsing Array of dictionaries in Swift using Codable - json

Question

I have a JSON response from an API and I cannot figure out how to convert it into an user object (a single user) using Swift Codable. This is the JSON (with some elements removed for ease of reading):
{
"user": [
{
"key": "id",
"value": "093"
},
{
"key": "name",
"value": "DEV"
},
{
"key": "city",
"value": "LG"
},
{
"key": "country",
"value": "IN"
},
{
"key": "group",
"value": "OPRR"
}
]
}

Answer 1

You could do it in two steps if you want to. First declare a struct for the received json
struct KeyValue: Decodable {
let key: String
let value: String
}
Then decode the json and map the result into a dictionary using the key/value pairs.
do {
let result = try JSONDecoder().decode([String: [KeyValue]].self, from: data)
if let array = result["user"] {
let dict = array.reduce(into: [:]) { $0[$1.key] = $1.value}
Then encode this dictionary into json and back again using a struct for User
struct User: Decodable {
let id: String
let name: String
let group: String
let city: String
let country: String
}
let userData = try JSONEncoder().encode(dict)
let user = try JSONDecoder().decode(User.self, from: userData)
The whole code block then becomes
do {
let decoder = JSONDecoder()
let result = try decoder.decode([String: [KeyValue]].self, from: data)
if let array = result["user"] {
let dict = array.reduce(into: [:]) { $0[$1.key] = $1.value}
let userData = try JSONEncoder().encode(dict)
let user = try decoder.decode(User.self, from: userData)
//...
}
} catch {
print(error)
}
A bit cumbersome but no manual key/property matching is needed.

Answer 2

you could try a struct with like this
struct Model: Codable {
struct User: Codable {
let key: String
let value: String
}
let singleuser: [User]
}

Answer 3

Create a struct with 2 variables key and value
public struct UserModel: Codable {
public struct User: Codable {
public let key: String
public let value: String
}
public let user: [User]
}
After that using JSONDecoder to decode your string.
func decode(payload: String) {
do {
let template = try JSONDecoder().decode(UserModel.self, from: payload.data(using: .utf8)!)
} catch {
print(error)
}
}