Creating Objects from JSON data using Google Places API in Swift - ios

Question

So I'm creating an app that uses the Google Places API to gather a list of restaurants. Using the API provides me with a JSON file full of details about each location like lat, long, rating, priceLevel, openNow, photos, etc. Below is the code used to gather said JSON from my given parameters:
func performGoogleSearch(radius: Double, type: String, price: Int ) {
let location = locationManager.location?.coordinate
let url: URL = URL(string: "https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=\(location?.latitude ?? 0),\(location?.longitude ?? 0)&radius=\(radius * 1609.34)&type=restaurant&maxprice=\(price)&key=AIzaSyBF0uwjr6BZc-Y-0kPsMBq2zNkl5EArioQ")!
let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
print(NSString(data: data!, encoding: String.Encoding.utf8.rawValue))
}
task.resume()
}
The data returned is a JSON like the following:
{
"html_attributions" : [],
"results" : [
{
"geometry" : {
"location" : {
"lat" : 37.7867167,
"lng" : -122.4111737
},
"viewport" : {
"northeast" : {
"lat" : 37.7881962302915,
"lng" : -122.4098846697085
},
"southwest" : {
"lat" : 37.7854982697085,
"lng" : -122.4125826302915
}
}
},
"icon" : "https://maps.gstatic.com/mapfiles/place_api/icons/lodging-71.png",
"id" : "3344890deedcb97b1c2d64814f92a02510ba39c8",
"name" : "Clift San Francisco",
"opening_hours" : {
"open_now" : false,
"weekday_text" : []
},
"photos" : [
{
"height" : 900,
"html_attributions" : [
"\u003ca href=\"https://maps.google.com/maps/contrib/114937580614387417622/photos\"\u003eClift San Francisco\u003c/a\u003e"
],
"photo_reference" : "CmRaAAAAwpWxfFJMJnK8G-LWJehCyUH5PFtepMF26XkZnXDRDo0wJMe-dAXLZ0zXGDmoEMi9n8YF5rYhgnr-EoDZFUawtiITYYocTJDAAjo1hw0sos4wVpfnx186o6pPgQWEv1f0EhDrydRti0bHEkhY4FNANV_KGhRmH8m7e6mO1sR2FlFxFuo5oSl00g",
"width" : 1155
}
],
"place_id" : "ChIJFUBxSY6AhYARwOaLV7TsLjw",
"price_level" : 4,
"rating" : 4.1,
"reference" : "CmRRAAAAA4IUvt3mHf2_QejiFA1acdgH2pg5h1_6GYDuVt-bzSwHqieSXmCAye5FRGJ0EjIM03WICU82MuKOiHor65j-e8rCDNEkltQnpoUX4AbCfRdybuqIPS5FxNsV_905or7BEhDNu3bKvzktrh2USu0zSNtoGhSkqf9WV1snRVufZ11kN6YgF961YQ",
"scope" : "GOOGLE",
"types" : [
"night_club",
"bar",
"lodging",
"restaurant",
"food",
"point_of_interest",
"establishment"
],
"vicinity" : "495 Geary Street, San Francisco"
},
{
"geometry" : {
"location" : {
"lat" : 37.78988329999999,
"lng" : -122.4091511
},
"viewport" : {
"northeast" : {
"lat" : 37.79135163029149,
"lng" : -122.4078268197085
},
"southwest" : {
"lat" : 37.78865366970849,
"lng" : -122.4105247802915
}
}
},
"icon" : "https://maps.gstatic.com/mapfiles/place_api/icons/lodging-71.png",
"id" : "547ceb15210b70b8734500183410bb10c644c395",
"name" : "Cornell Hotel De France",
"opening_hours" : {
"open_now" : true,
"weekday_text" : []
},
"photos" : [
{
"height" : 315,
"html_attributions" : [
"\u003ca href=\"https://maps.google.com/maps/contrib/114711934191765864568/photos\"\u003eCornell Hotel De France\u003c/a\u003e"
],
"photo_reference" : "CmRaAAAAJ3kTtFbeGT-8NWKbf9TPlN6gL6daO5zKq9DNZnzShZ-CcPUJnxMaVZybHZ0sGefM72WV01VcXr1AJWNKOSifZ63DIxxutKJ0ecqPUkM73LZLM-LO_eqsaWBRH8QN6PLYEhDykcPC3JAyDEDWpdiu3FP8GhRiJrTRNpnYQi1DDztzCRVKAM4N_A",
"width" : 851
}
],
"place_id" : "ChIJs6F3JYyAhYARDiVdBrmivCs",
"price_level" : 4,
"rating" : 4.2,
"reference" : "CmRRAAAAK05VMbTrE3cDxZreuM-Z0rbXcfdT4nflU0D17oCIwaF2RVbF85ch-1qKfRAGtMPxuuBvzw9sO-Y1rwRin-fEmzvgtiPsy8X_R2kfzh7rHX8iS8gJKc1QyTk2H4XU2O4hEhDMcIcjK5fWFvnGrJWxHgC6GhQAOkKXMCm7IjhOeOD__ZqzFlosmg",
"scope" : "GOOGLE",
"types" : [
"clothing_store",
"store",
"lodging",
"restaurant",
"food",
"point_of_interest",
"establishment"
],
"vicinity" : "715 Bush Street, San Francisco"
}
],
"status" : "OK"
}
I have an object called "Location" that hopes to take the JSON as a parameter to fill in its respective values. I would like to get to the point where I can take this JSON and turn it into an array of my "Location" struct populated with one "Location" for each restaurant returned in the Google Places API JSON.
Here is the "Location" struct:
import Foundation
struct Location: Codable {
var lat: Double
var long: Double
var icon: String?
var id: String?
var name: String
var openNow: Bool?
var photos: [String : Any]?
var placeID: String?
var priceLevel: Int?
var rating: Double?
var types: [String]?
init?(json: [String: Any]) {
guard let lat = json["lat"] as? Double,
let long = json["lng"] as? Double,
let icon = json["icon"] as? String,
let id = json["id"] as? String,
let name = json["name"] as? String,
let openNow = json["open_now"] as? Bool,
let photos = json["photos"] as? [String : Any],
let placeID = json ["place_id"] as? String,
let priceLevel = json["price_level"] as? Int,
let rating = json["rating"] as? Double,
let types = json["types"] as? [String]? else {
return nil
}
self.lat = lat
self.long = long
self.icon = icon
self.id = id
self.name = name
self.openNow = openNow
self.photos = photos
self.placeID = placeID
self.priceLevel = priceLevel
self.rating = rating
self.types = types
}
}
This struct is a start but is clearly lacking as I do not know how to go about taking the data from the JSON to make an array of this "Location" struct. Any guidance would be appreciated.

Answer 1

You can use JSONDecoder
let decoder = JSONDecoder()
do {
let locations = try decoder.decode([Location].self, from: yourJson)
print(locations)
} catch {
print(error.localizedDescription)
}
Also you can nest structs to represent your data which you're probably going to have to do. Have a look at "More Complex Nested Response" on this guide to JSON parsing

Answer 2

I eventually changed my "Location" struct to
Not be codable
Take each property as a parameter as opposed to taking the whole JSON dictionary as the parameter
In the "performGoogleSearch()" function, I essentially had to keep converting values of the dictionary into dictionaries themselves in order to reach deeper into the file. I then used each value I could get out of the JSON file and used them to create an object of my class. I then appended each object to my array of results.
func performGoogleSearch(radius: Double, type: String, price: Int ) {
let location = locationManager.location?.coordinate
let url: URL = URL(string: "https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=\(location?.latitude ?? 0),\(location?.longitude ?? 0)&radius=\(radius * 1609.34)&type=restaurant&maxprice=\(price)&key=AIzaSyBF0uwjr6BZc-Y-0kPsMBq2zNkl5EArioQ")!
let task = URLSession.shared.dataTask(with: url) {(data, response, error) in
let jsonObject = try? JSONSerialization.jsonObject(with: data! as Data, options: [])
if let jsonArray = jsonObject as? [String: Any] {
if let results = jsonArray["results"] as! [Any]?{
for result in results {
if let locationDictionary = result as? [String : Any] {
let geometry = locationDictionary["geometry"]! as! [String : Any]
let location = geometry["location"]! as! [String : Any]
let lat = location["lat"]
let long = location["lng"]
let openingHours = locationDictionary["opening_hours"] as? [String : Any]
let openNow = openingHours?["open_now"]
let photos = locationDictionary["photos"] as? [[String : Any]]
let newLocation = Location(lat: lat as! Double, long: long as! Double, id: locationDictionary["id"] as? String, name: locationDictionary["name"] as! String, openNow: openNow as? Int, photos: photos, placeID: locationDictionary["place_id"] as? String, priceLevel: locationDictionary["price_level"] as? Int, rating: locationDictionary["rating"] as? Double, types: locationDictionary["types"] as? [String])
googleResults.append(newLocation!)
}
}
print("Results: \(googleResults.count)")
let randomInt = Int(arc4random_uniform(UInt32(googleResults.count)))
print("RandomInt: \(randomInt)")
if googleResults.count != 0 {
self.googleResult = googleResults[randomInt]
self.annotation = MapBoxAnnotation(coordinate: CLLocationCoordinate2D(latitude: (self.self.googleResult?.lat)!, longitude: (self.self.googleResult?.long)!), title: self.googleResult?.name, subtitle: nil)
}
}
}
DispatchQueue.main.async {
self.animateResultView()
}
}
task.resume()
Location struct:
struct Location {
var lat: Double
var long: Double
var id: String?
var name: String
var openNow: Int?
var photos: [[String : Any]]?
var placeID: String?
var priceLevel: Int?
var rating: Double?
var types: [String]?
init?(lat: Double, long: Double, id: String?, name: String, openNow: Int?, photos: [[String : Any]]?, placeID: String?, priceLevel: Int?, rating: Double?, types: [String]?) {
self.lat = lat
self.long = long
self.id = id
self.name = name
self.openNow = openNow
self.photos = photos
self.placeID = placeID
self.priceLevel = priceLevel
self.rating = rating
self.types = types
}
}