SwiftUI custom error with additional detail for support/tracking - swiftui

Question

I want to track additional information about errors to help support issues and be proactive where errors/bugs are encountered. I am new to iOS/Swift, but I have followed a few YouTube videos and posts on error handling to alert users of an error (this was the most up to date/best one I found) but I also want to provide more detail as well to help support. I created a custom error:
enum CustomError: Error {
case apiDecodingError
...
}
and extended it:
extension CustomError: LocalizedError {
var errorDescription: String? {
switch self {
case .apiDecodingError:
return NSLocalizedString("Problem understanding service response.", comment: "")
...
}
}
}
but I cannot add additional properties to the extension because: Extensions must not contain stored properties.
When I catch and throw a custom error from, for example, decoding the response of an api call:
} catch let DecodingError.keyNotFound(key, context) {
print("Key '\(key)' not found:", context.debugDescription)
print("codingPath:", context.codingPath)
throw CustomError.DecodingError
This makes for a simplified user message:
but I also want to send the detail to the bug tracking system with the specific problem, such as the key which was having the problem.
} catch {
print("\(error)")
let properties = ["Error" : error.localizedDescription]
Analytics.trackEvent("UpdateNotificationSetting", withProperties: properties, flags: .critical)
isAlertErrorPresented = true
errorAlert = ErrorAlert(error: error)
}
I would like to send along the detail but that means the custom error needs additional information from the inner error. I'm a novice at SwiftUI, is there a standard way to address this?

Answer 1

You can do it by expanding CustomError
enum CustomError: LocalizedError{
///Takes in any error and makes it compatible with `LocalizedError`
case error(Error)
///Allows for throwing an error with a custom description
case custom(description: String, failureReason: String? = nil, helpAnchor: String? = nil, recoverySuggestion: String? = nil)
///Can be used as a custom key using localization features
case customKey
///Mimic your decoding error
case apiDecodingError(key: String, path: String)
var errorDescription: String?{
switch self{
case .error(let error):
return error.localizedDescription
case .custom(let description, _ , _, _):
return description
case .apiDecodingError(let key, path: let path):
return String(format: "Key %# not found: codingPath: %#", key, path)
default:
///Add `customKeyErrorDescription` to Localizable.strings
return NSLocalizedString("\(self)" + "ErrorDescription", comment: "AppError")
}
}
var failureReason: String?{
switch self{
case .error(let error):
let nsError = error as NSError
return nsError.localizedFailureReason
case .custom(_ , let failureReason , _, _):
return failureReason
case .apiDecodingError(_, _):
return nil
default:
///Add `customKeyFailureReason` to Localizable.strings
return NSLocalizedString("\(self)" + "FailureReason", comment: "AppError")
}
}
var helpAnchor: String?{
switch self{
case .error(let error):
let nsError = error as NSError
return nsError.helpAnchor
case .custom(_ , _ , let helpAnchor, _):
return helpAnchor
case .apiDecodingError(_, _):
return nil
default:
///Add `customKeyHelpAnchor` to Localizable.strings
return NSLocalizedString("\(self)" + "HelpAnchor", comment: "AppError")
}
}
var recoverySuggestion: String?{
switch self{
case .error(let error):
let nsError = error as NSError
return nsError.localizedRecoverySuggestion
case .custom(_, _ , _, let recoverySuggestion):
return recoverySuggestion
case .apiDecodingError(_, _):
return nil
default:
///Add `customKeyRecoverySuggestion` to Localizable.strings
return NSLocalizedString("\(self)" + "RecoverySuggestion", comment: "AppError")
}
}
}
Then you can pass along any standard error
do{
}catch{
CustomError.error(error)
}