Loop through JSON Object Swift 5 - ios

Question

I am trying to iterate through a JSON object and obtain specific values in the swift programming language.
I am receiving a JSON like so
let json = try? JSONSerialization.jsonObject(with: data, options: []) as? [String : Any],
let charges = json["charges"] as? [String:Any]
json:
{
object: 'list',
data: [
{
id: 'ch_1IWQEfKn7R1M6tqnhrpyIhMk',
object: 'charge',
amount: 555,
amount_captured: 555,
amount_refunded: 0,
application: 'ca_IXRQuoBh5mSJXXpEccXssma6Oz0u3HjX',
application_fee: 'fee_1IWQEfKn7R1M6tqnvTHQeSEF',
application_fee_amount: 6,
balance_transaction: 'txn_1IWQEfKn7R1M6tqnkK9LCNuM',
billing_details: [Object],
calculated_statement_descriptor: 'TEST ACCOUNT',
captured: true,
created: 1616090777,
currency: 'usd',
customer: null,
description: null,
destination: null,
dispute: null,
disputed: false,
failure_code: null,
failure_message: null,
fraud_details: {},
invoice: null,
livemode: false,
metadata: {},
on_behalf_of: null,
order: null,
outcome: [Object],
paid: true,
payment_intent: 'pi_1IWQEeKn7R1M6tqnYbGfFCzg',
payment_method: 'pm_1IWQEeKn7R1M6tqnKLxSg6vZ',
payment_method_details: [Object],
receipt_email: null,
receipt_number: null,
receipt_url: 'https://pay.stripe.com/receipts/acct_1ISouBKn7R1M6tqn/ch_1IWQEfKn7R1M6tqnhrpyIhMk/rcpt_J8hdy05N6VfOmRECdumpti8Jiljz2Et',
refunded: false,
refunds: [Object],
review: null,
shipping: null,
source: null,
source_transfer: null,
statement_descriptor: null,
statement_descriptor_suffix: null,
status: 'succeeded',
transfer_data: null,
transfer_group: null
},
{
id: 'ch_1IU62QKn7R1M6tqnbXXlOpch',
object: 'charge',
amount: 5599,
amount_captured: 5599,
amount_refunded: 0,
application: 'ca_IXRQuoBh5mSJXXpEccXssma6Oz0u3HjX',
application_fee: 'fee_1IU62RKn7R1M6tqnLle3zblA',
application_fee_amount: 56,
balance_transaction: 'txn_1IU62RKn7R1M6tqn3ttu9F3N',
billing_details: [Object],
calculated_statement_descriptor: 'TEST ACCOUNT',
captured: true,
created: 1615536482,
currency: 'usd',
customer: null,
description: null,
destination: null,
dispute: null,
disputed: false,
failure_code: null,
failure_message: null,
fraud_details: {},
invoice: null,
livemode: false,
metadata: {},
on_behalf_of: null,
order: null,
outcome: [Object],
paid: true,
payment_intent: 'pi_1IU62NKn7R1M6tqnWSOLJVge',
payment_method: 'pm_1IU62PKn7R1M6tqnIyOUgUMX',
payment_method_details: [Object],
receipt_email: null,
receipt_number: null,
receipt_url: 'https://pay.stripe.com/receipts/acct_1ISouBKn7R1M6tqn/ch_1IU62QKn7R1M6tqnbXXlOpch/rcpt_J6Id30gjIhQU6AWPBHgUXoujbhFOTyf',
refunded: false,
refunds: [Object],
review: null,
shipping: null,
source: null,
source_transfer: null,
statement_descriptor: null,
statement_descriptor_suffix: null,
status: 'succeeded',
transfer_data: null,
transfer_group: null
},
{
id: 'ch_1IU60cKn7R1M6tqny9o2NV5W',
object: 'charge',
amount: 1000,
amount_captured: 1000,
amount_refunded: 0,
application: 'ca_IXRQuoBh5mSJXXpEccXssma6Oz0u3HjX',
application_fee: 'fee_1IU60cKn7R1M6tqn95nUHETe',
application_fee_amount: 10,
balance_transaction: 'txn_1IU60cKn7R1M6tqnZKNbSEXf',
billing_details: [Object],
calculated_statement_descriptor: 'TEST ACCOUNT',
captured: true,
created: 1615536370,
currency: 'usd',
customer: null,
description: null,
destination: null,
dispute: null,
disputed: false,
failure_code: null,
failure_message: null,
fraud_details: {},
invoice: null,
livemode: false,
metadata: {},
on_behalf_of: null,
order: null,
outcome: [Object],
paid: true,
payment_intent: 'pi_1IU60ZKn7R1M6tqnrUSK1TQD',
payment_method: 'pm_1IU60bKn7R1M6tqnAUHQXqJG',
payment_method_details: [Object],
receipt_email: null,
receipt_number: null,
receipt_url: 'https://pay.stripe.com/receipts/acct_1ISouBKn7R1M6tqn/ch_1IU60cKn7R1M6tqny9o2NV5W/rcpt_J6Ib5PEZQzEgyXWoOwKcxZ9x7mByCVu',
refunded: false,
refunds: [Object],
review: null,
shipping: null,
source: null,
source_transfer: null,
statement_descriptor: null,
statement_descriptor_suffix: null,
status: 'succeeded',
transfer_data: null,
transfer_group: null
}
],
has_more: true,
url: '/v1/charges'
}
How can I iterate through the JSON object to receive "amount", "currency", and "id".
For example PSUEDO:
for item in charges {
print(item["amount"])
print(item["currency"])
print(item["id"])
}
I may be initializing the json improperly such as
json["charges"] as? [String:Any]

Answer 1

You shouldn't use try ? - This throws away errors. Always use do/try/catch so that you handle any errors that occur, even if you just print them.
JSONSerialization and decoding JSON to arrays and dictionaries isn't best practice. It is much better to create suitable structs that conform to Codable and use JSONDecoder.
struct Response: Codable {
var object: String
var hasMore: Bool
var data: [ResponseData]
var url: String
enum CodingKeys: String, CodingKey {
case object
case hasMore = "has_more"
case url
case data
}
}
struct ResponseData: Codable {
var amount: Int
var currency: String
var id: String
}
For simplicity I have't added all of the properties to the ResponseData struct, just the ones you have said you are interested in
do {
let json = try JSONDecoder().decode(Response.self, from: data)
json.data.forEach { charge in
print(charge.id)
print(charge.currency)
print(charge.ammount)
}
} catch {
print("Error! \(error)")
}