Swift 3 - Compare key values from two different dictionaries and update one of them if key value matches - swift

Question

I have two arrays of dictionaries:
Dict 1 =
[{"id":"100", "name":"Matt", "phone":"0404040404", "address":"TBC"}
,{"id":"110", "name":"Sean", "phone":"0404040404", "address":"TBC"}
, {"id":"120", "name":"Luke", "phone":"0404040404", "address":"TBC"}]
Dict 2 =
[{"id":"100", "address":"1 Main Street"}
,{"id":"110", "address":"2 Main Road"}
, {"id":"120", "address":"3 Main Street"}]
I want to compare the key:value pair, id , of each dictionary in Dict 2 against Dict 1, and if the id matches, update the corresponding address in Dict 1 from the value in Dict2.
So the desired output should be:
Dict 1 =
[{"id":"100", "name":"Matt", "phone":"0404040404", "address":"1 Main Street"}
,{"id":"110", "name":"Sean", "phone":"0404040404", "address":"2 Main Road"}
, {"id":"120", "name":"Luke", "phone":"0404040404", "address":"3 Main Street"}]
EDIT
As requested, here is more information regarding how I am parsing the data. I am getting Dict1 and Dict2 as response to HTTP URL call btw. And also, I use dictionaries of the type [Dictionary] while parsing.
let Task1 = URLSession.shared.dataTask(with: URL!) { (Data, response, error) in
if error != nil {
print(error)
} else {
if let DataContent = Data {
do {
let JSONresponse1 = try JSONSerialization.jsonObject(with: DataContent, options: JSONSerialization.ReadingOptions.mutableContainers)
print(JSONresponse1)
for item in JSONresponse1 as! [Dictionary<String, Any>] {
//Parse here
}
}
catch { }
DispatchQueue.main.async(execute: {
self.getAddressTask()
})
}
}
}
Task1.resume()
}
JSONResponse1 is Dict 1
Then inside the getAddressTask() func called above, I do the HTTP URL call to get Dict 2
let AddressTask = URLSession.shared.dataTask(with: URL2!) { (Data, response, error) in
if error != nil {
print(error)
} else {
if let DataContent = Data {
do {
let JSONresponse2 = try JSONSerialization.jsonObject(with: timeRestrictionsDataContent, options: JSONSerialization.ReadingOptions.mutableContainers)
print(JSONresponse2)
for item in JSONresponse2 as! [Dictionary<String, Any>] {
//Parse here
}
catch { }
self.compileDictionaries()
}
}
}
AddressTask.resume()
JSONResponse2 is Dict2
Inside compileDictionaries() i would like to get the desired output as shown above.

Answer 1

You should struct your data using Codable protocol and create a mutating method to update your contact. If you need an array of your contacts once you have them updated all you need is to encode your contacts using JSONEncoder:
struct Contact: Codable, CustomStringConvertible {
let id: String
var address: String?
var name: String?
var phone: String?
mutating func update(with contact: Contact) {
address = contact.address ?? address
name = contact.name ?? name
phone = contact.phone ?? phone
}
var description: String {
return "ID: \(id)\nName: \(name ?? "")\nPhone: \(phone ?? "")\nAddress: \(address ?? "")\n"
}
}
Playground testing:
let json1 = """
[{"id":"100", "name":"Matt", "phone":"0404040404", "address":"TBC"},
{"id":"110", "name":"Sean", "phone":"0404040404", "address":"TBC"},
{"id":"120", "name":"Luke", "phone":"0404040404", "address":"TBC"}]
"""
let json2 = """
[{"id":"100", "address":"1 Main Street"},
{"id":"110", "address":"2 Main Road"},
{"id":"120", "address":"3 Main Street"}]
"""
var contacts: [Contact] = []
var updates: [Contact] = []
do {
contacts = try JSONDecoder().decode([Contact].self, from: Data(json1.utf8))
updates = try JSONDecoder().decode([Contact].self, from: Data(json2.utf8))
for contact in updates {
if let index = contacts.index(where: {$0.id == contact.id}) {
contacts[index].update(with: contact)
} else {
contacts.append(contact)
}
}
let updatedJSON = try JSONEncoder().encode(contacts)
print(String(data: updatedJSON, encoding: .utf8) ?? "")
} catch {
print(error)
}
This will print:
[{"id":"100","phone":"0404040404","name":"Matt","address":"1 Main
Street"},{"id":"110","phone":"0404040404","name":"Sean","address":"2
Main
Road"},{"id":"120","phone":"0404040404","name":"Luke","address":"3
Main Street"}]