Api调用返回错误**keyNotFound..***

Question

我正在尝试进行api调用，我正在查询中构建api并像往常一样解析它，但我遇到了错误：

keyNotFound(编码键(字符串值："locationType"，intValue:nil(，Swift。DecodingError.Context(编码路径：[_JSONKey(字符串值；"Index 0"，intValue:0(]，debugDescription:"；没有与键CodingKeys(字符串值："locationType"，intValue:nil(("locationType"(关联的值&"；，underlyingError：nil(**(

获取数据：

func fetchData(completionHandler: @escaping ([Root]) -> Void) {

let queryItems = [URLQueryItem(name: "lat", value: "51.176519"),URLQueryItem(name: "lng", value: "-0.622557"),URLQueryItem(name: "date", value: "2020-11")]
var urlComponents = URLComponents(string: "https://data.police.uk/api/crimes-street/all-crime")
urlComponents?.queryItems = queryItems
guard let combinedUrl = urlComponents?.url else {return}
print(combinedUrl)
let task = URLSession.shared.dataTask(with: combinedUrl,completionHandler : { (data, response, error) in
if let error = error {
print("Error with fetching accounts: (error)")
return
}
guard let httpResponse = response as? HTTPURLResponse,
(200...400).contains(httpResponse.statusCode) else {
print("Error with the response , unexpected status code:(response)")
return
}
guard let data = data else {return}
do {
let decoder = JSONDecoder()
let dataSummary = try decoder.decode([Root].self, from: data)
completionHandler(dataSummary.self ?? [])
} catch {
print(error)
}
})
task.resume()
}

ViewController:

override func viewDidLoad() {
super.viewDidLoad()
networking.fetchData{[weak self] (jsonValues) in
self?.jsonValues = jsonValues ;print("JSON values Inside closure : (jsonValues)")
}
print("JSON values outside closure: (jsonValues)")
}

根结构：

public struct Root: Codable {
public let category, location_Type: String
public let location: Location
public let context: String
public let outcomeStatus: OutcomeStatus
public let persistentId: String
public let id: Int
public let locationSubtype, month: String
public init(category: String, locationType: String, location: Location, context: String, outcomeStatus: OutcomeStatus, persistentId: String, id: Int, locationSubtype: String, month: String) {
self.category = category
self.locationType = locationType
self.location = location
self.context = context
self.outcomeStatus = outcomeStatus
self.persistentId = persistentId
self.id = id
self.locationSubtype = locationSubtype
self.month = month
}

}

任何帮助都将是惊人的！

Answer 1

错误表明它在API响应中找到了nil，因为我没有考虑到响应可以是nil我在根结构中设置了可选的值，然后它成功解析。

public let category, location_Type: String?
public let location: Location
public let context: String
public let outcomeStatus: OutcomeStatus?
public let persistentId: String?
public let id: Int
public let locationSubtype, month: String?