VaporErrorKit

Install using SPM

.package(url: "https://github.com/Einstore/VaporErrorKit.git", from: "0.0.1")

Concept

Allow framework agnostic server side libraries to have a common error type while allowing easy error handling within the final app.

WebError libraries consist of three products:

• VaporErrorKit - This library
• NIOErrorKit - WebErrorKit extended for use with NIO
• WebErrorKit - Base types, protocols and tools; to be used in libraries

Basic use

Conform your error to WebError from WebErrorKit package

If your error is a String RawRepresentable (String enum) you get code property for free (see response output below)

enum MyError: String, WebError {

    case somethingHasHappened
    
}

above error will generate following error response:

// Status 500
{
    "code": "my_error.something_has_happened"
}

Custom use

enum MyError: String, WebError {
    
    case somethingHasHappened
    
    var statusCode: Int {
        return 417
    }
    
    var reason: String? {
        return "Something has happened!!!"
    }
    
}

above error will generate following error response:

// Status 417
{
    "code": "my_error.something_has_happened",
    "reason": "Something has happened!!!"
}

Custom enum types

For errors that don’t conform to String and RawRepresentable you can use SerializableWebError as follows:

enum MyError: SerializableWebError {

    case itsComplicated(complication: String)

    var serializedCode: String {
        switch self {
        case .itsComplicated(complication: let c):
            return "its_complicated:\(c)"
        }
    }

}

above error will generate following error response:

// Status 500
{
    "code": "my_error.its_complicated:huge_problem"
}

Integration with Vapor

WebErrorMiddleware

Register WebErrorMiddleware in your configure method

s.register(MiddlewareConfiguration.self) { c in
    // Create _empty_ middleware config
    var middlewares = MiddlewareConfiguration()

    // Catches errors and converts to HTTP response
    try middlewares.use(c.make(WebErrorMiddleware.self))

    return middlewares
}

Handling Swift.Error

• Code of the error message will be “snake cased” type of the error
• Status code is set to 500
• Reason is localizedDescription

Handling Vapor.AbortError

• Code of the error message will be “snake cased” type of the error while the reason and status code works the same

Base error types.

Author

Ondrej Rafaj @rafiki270

License

MIT; Copyright 2019 - Einstore