Issues with Codable Arrays and Alamofire - swift

Question

I am attempting to submit the following request through Alamofire and I am receiving the following error:
2020-01-13 09:41:05.912103-0600 AFNetworkingDemo[29720:604258] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'Invalid type in JSON write (__SwiftValue)'
My assumption is that it is the way I am defining the arrays within the object (I was following some of the material found here: https://benscheirman.com/2017/06/swift-json)
struct ProgramRequest: Codable {
var userID: Int
var programData: ProgramData
var json: Constants.Json {
return [
"userID": userID,
"programData": programData.json,
]
}
}
struct ProgramData: Codable {
var airhotel: [AirHotel]
var security: [Security]
var json: Constants.Json {
return [
"airhotel": airhotel,
"security": security
]
}
}
struct AirHotel: Codable {
var id: Int
var loyaltyNumber: String
var json: Constants.Json {
return [
"id": id,
"loyaltyNumber": loyaltyNumber
]
}
}
struct Security: Codable {
var vendorCode: String
var loyaltyNumber: String
var json: [String: Any] {
return [
"vendorCode": vendorCode,
"loyaltyNumber": loyaltyNumber
]
}
}
The json dictionary at each level is to render the objects appropriately for Alamofire. For a given example, if I print it out using:
let jsonEncoder = JSONEncoder()
jsonEncoder.outputFormatting = .prettyPrinted
let jsonData = try jsonEncoder.encode(programRequest)
if let jsonString = String(data: jsonData, encoding: .utf8) {
print(jsonString) #1
}
print("IsValidJSON: ", JSONSerialization.isValidJSONObject(programRequest)) #2
print(programRequest.json) #3
urlRequest = try! JSONEncoding.default.encode(urlRequest, with: programRequest.json) #4 causes error
1 output:
{
"userID" : 10021,
"programData" : {
"airhotel" : [],
"security" : [
{
"vendorCode" : "sty",
"loyaltyNumber" : "Loyal1"
}
]
}
}
2 output
IsValidJSON: false
3 output - I noticed the AFNetworkingDemo.Security within the output, is that what Alamofire JSONEncoding on:
["programData": ["security": [AFNetworkingDemo.Security(vendorCode: "sty", loyaltyNumber: "Loyal1")], "airhotel": []], "userID": 10021]
My question would be, what changes to I need to make in the AirHotel and Security sections of ProgramRequest in order to resolve my issues with Alamofire?

Answer 1

Step 1: Stop reinventing Codable
The json computed property is not needed and wrongly used.
Remove it.
struct ProgramRequest: Codable {
var userID: Int
var programData: ProgramData
}
struct ProgramData: Codable {
var airhotel: [AirHotel]
var security: [Security]
}
struct AirHotel: Codable {
var id: Int
var loyaltyNumber: String
}
struct Security: Codable {
var vendorCode: String
var loyaltyNumber: String
}
Step 2: Start using Codable
Now given a programRequest, eg. like this
let programRequest = ProgramRequest(userID: 1, programData: ProgramData(airhotel: [AirHotel(id: 1, loyaltyNumber: "loyaltyNumber")], security: [Security(vendorCode: "loyaltyNumber", loyaltyNumber: "loyaltyNumber")]))
You can generate the correct Data value representing the JSON simply writing
let data = try JSONEncoder().encode(programRequest)
And (if you want) you can convert data intro a String
let json = String(data: data, encoding: .utf8)
Output
Optional("{\"userID\":1,\"programData\":{\"airhotel\":[{\"id\":1,\"loyaltyNumber\":\"loyaltyNumber\"}],\"security\":[{\"vendorCode\":\"loyaltyNumber\",\"loyaltyNumber\":\"loyaltyNumber\"}]}}")
That's it