Decoding Nested Arrays from RapidAPI in Swift

Other Questions RapidAPI
1

I am exploring a COVID-19 API via RapidAPI and obtained the following response from an endpoint:

[0:
"country":"Canada"
"provinces":[

    0:{
    "province":"Alberta"
    "confirmed":754
    "recovered":0
    "deaths":9
    "active":0
    }...etc]

"latitude":56.130366
"longitude":-106.346771
"date":"2020-04-01"
}
]

My goal is to extract the ‘provinces’ data, so in Xcode I have created models as follows:

struct Nation: Codable {
    let name: String
    let regions: [Region]
}

struct Region: Codable {
    let name: String
    let confirmedCases: Int
    let recoveredCases: Int
    let fatalities: Int
    let activeCases: Int
}

While I believe these models are set up correctly, the parsing fails unless I comment out the ‘regions’ variable in Nation:

struct Nation: Codable {
    let name: String
    //let regions: [Region]
}

As a result, I can print the country’s name, but not the provinces. This leads me to think there’s an issue with my model structure. What might I be missing? I’ve referred to examples, and this setup should function correctly.

UPDATE: Here’s more code for context:

override func viewDidLoad() {
    super.viewDidLoad()

    Service.shared.fetchInfo(url: "url", hostName: "host", apiKey: "12345", requiresKey: true) { response in
        
        if let responseData = response {
            if let nations = try? JSONDecoder().decode([Nation].self, from: responseData) {
                // Assign the first province's name to a variable
                let province: String = nations[0].regions[0].name
                self.provinceOutput = province
            }
            
            DispatchQueue.main.async { [weak self] in
                // Output the province name
                print(self?.provinceOutput)
            }
        }
    }
}
2

You need to adjust your model to match the JSON keys and structure. Update your models like this:

struct Nation: Codable {
    let country: String
    let provinces: [Region]
    let latitude: Double
    let longitude: Double
    let date: String
}

struct Region: Codable {
    let province: String
    let confirmed: Int
    let recovered: Int
    let deaths: Int
    let active: Int
}

Also, ensure your JSONDecoder is correctly set for decoding. This should match the JSON response structure you shared. The key names in the models must exactly match the JSON keys. You might also want to double-check any optional fields or provide default values if some fields can be missing. Re-run your parsing with these adjustments.