Мой код предложения. Основано на ответах @datinc и @ Mario-Hendricks
Вы, конечно, должны заменить dlog_Error на вызов функции входа в систему.
Такая структура кода должна предотвращать сбой вашего приложения в случае ошибки.
Для получения appStoreAppVersion не обязательно, и не должно привести к фатальным ошибкам.
И все же, с такой структурой кода, вы по-прежнему будете регистрировать вашу нефатальную ошибку.
class func appStoreAppVersion() -> String?
{
guard let bundleInfo = NSBundle.mainBundle().infoDictionary else {
dlog_Error("Counldn't fetch bundleInfo.")
return nil
}
let bundleId = bundleInfo[kCFBundleIdentifierKey as String] as! String
// dbug__print("bundleId = \(bundleId)")
let address = "http://itunes.apple.com/lookup?bundleId=\(bundleId)"
// dbug__print("address = \(address)")
guard let url = NSURLComponents.init(string: address)?.URL else {
dlog_Error("Malformed internet address: \(address)")
return nil
}
guard let data = NSData.init(contentsOfURL: url) else {
if Util.isInternetAvailable() {
dlog_MajorWarning("Web server request failed. Yet internet is reachable. Url was: \(address)")
}// else: internet is unreachable. All ok. It is of course impossible to fetch the appStoreAppVersion like this.
return nil
}
// dbug__print("data.length = \(data.length)")
if data.length < 100 { //: We got 42 for a wrong address. And aproximately 4684 for a good response
dlog_MajorWarning("Web server message is unexpectedly short: \(data.length) bytes")
}
guard let response = try? NSJSONSerialization.JSONObjectWithData(data, options: []) else {
dlog_Error("Failed to parse server response.")
return nil
}
guard let responseDic = response as? [String: AnyObject] else {
dlog_Error("Not a dictionary keyed with strings. Response with unexpected format.")
return nil
}
guard let resultCount = responseDic["resultCount"] else {
dlog_Error("No resultCount found.")
return nil
}
guard let count = resultCount as? Int else { //: Swift will handle NSNumber.integerValue
dlog_Error("Server response resultCount is not an NSNumber.integer.")
return nil
}
//:~ Determine how many results we got. There should be exactly one, but will be zero if the URL was wrong
guard count == 1 else {
dlog_Error("Server response resultCount=\(count), but was expected to be 1. URL (\(address)) must be wrong or something.")
return nil
}
guard let rawResults = responseDic["results"] else {
dlog_Error("Response does not contain a field called results. Results with unexpected format.")
return nil
}
guard let resultsArray = rawResults as? [AnyObject] else {
dlog_Error("Not an array of results. Results with unexpected format.")
return nil
}
guard let resultsDic = resultsArray[0] as? [String: AnyObject] else {
dlog_Error("Not a dictionary keyed with strings. Results with unexpected format.")
return nil
}
guard let rawVersion = resultsDic["version"] else {
dlog_Error("The key version is not part of the results")
return nil
}
guard let versionStr = rawVersion as? String else {
dlog_Error("Version is not a String")
return nil
}
return versionStr.e_trimmed()
}
extension String {
func e_trimmed() -> String
{
return stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
}
}