Hands-On Server-Side Web Development with Swift

Handling errors

Kitura provides you with a struct to handle initialization errors in InitializationError.swift:

// File: /Application/InitializationError.swiftimport Foundationpublic struct InitializationError: Error { // [1]    let message: String    init(_ msg: String) {        message = msg    }}extension InitializationError: LocalizedError { // [2]    public var errorDescription: String? {        return message    }}

The following features are implemented:

1. The InitializationError() struct is inherited from the Error() struct
2. The InitializationError() struct is extended from LocalizedError

The InitializationError() struct does no more than offer you a chance to modify the error message. You can, for example, replace an error message with a localized version ...