I am getting an error trying to fetch data using Square's customer API.

debugDescription: "No value associated with key CodingKeys(stringValue: \"customer\", intValue: nil) (\"customer\").", underlyingError: nil))

Here is an example of the returned data:

{
  "customers": [
    {
      "id": "MJAG403GV96BX367R56N4FZJTG",
      "created_at": "2021-11-07T04:18:21.42Z",
      "updated_at": "2021-11-07T23:10:20Z",
      "given_name": "Test",
      "family_name": "Customer",
      "email_address": "email@email.com",
      "address": {
        "address_line_1": "123 Any St",
        "locality": "Somewhere",
        "administrative_district_level_1": "CA",
        "postal_code": "55555"
      },
      "phone_number": "+12025551234",
      "preferences": {
        "email_unsubscribed": false
      },
      "creation_source": "DIRECTORY",
      "segment_ids": [
        "MLPYEYRXNK0KW.REACHABLE"
      ],
      "version": 1
    }
  ]
}

And this is what I have for the model currently:

struct arrayOfCustomers: Codable {
    var customer: [Customer]
}

struct Customer: Codable, Identifiable  {
    var id: String
    var created_at: Date
    var updated_at: Date
    var given_name, family_name, email_address, phone_number: String?

    struct address: Codable {
        var address_line_1, locality, administrative_district_level_1, postalCode: String?
        var country: String?
    }
}

I have use "Ducky" (helper for JSON) and got this

import Foundation

struct Square: Decodable {
  struct Customer: Decodable, Identifiable {
    struct Address: Decodable {
      let addressLine1: String
      let locality: String
      let administrativeDistrictLevel1: String
      let postalCode: String
    }

    struct Preference: Decodable {
      let emailUnsubscribed: Bool
    }

    let id: String
    let createdAt: Date
    let updatedAt: Date
    let givenName: String
    let familyName: String
    let emailAddress: String
    let address: Address
    let phoneNumber: String
    let preferences: Preference
    let creationSource: String
    let segmentIds: [String]
    let version: Int
  }

  let customers: [Customer]
}

If you use. You able to use camelCase

let decoder = JSONDecoder()
decoder.keyDecodingStrategy = .convertFromSnakeCase
decoder.dateDecodingStrategy = .iso8601

Post your code that decodes the JSON, that's likely where the problem lies.

Here is the code that decodes the JSON:

class apiCall {
func getCustomers(completion:@escaping (arrayOfCustomers) -> ()) {
    guard let url = URL(string: "https://connect.squareup.com/v2/customers") else {
        print("Could not use URL")
        return
    }

    var request = URLRequest(url: url)
    request.httpMethod = "GET"
    request.setValue("application/json", forHTTPHeaderField: "Content-Type")
    request.setValue("2021-10-20", forHTTPHeaderField: "Square-Version")
    request.setValue("Bearer (Access Token is in my actual code)", forHTTPHeaderField: "Authorization")

    URLSession.shared.dataTask(with: request) { (data, _, _) in
        let customers = try! JSONDecoder().decode(arrayOfCustomers.self, from: data!)
            print(customers)
        for customer in customers.customer {
            print(customer.given_name)
        }
            DispatchQueue.main.async {
                completion(customers)
            }
    }
    .resume()
}
}