Swiftpack.co - Package - IBM-Swift/Kitura-NIO


Swift 5.0 APIDoc Build Status - Master macOS Linux Apache 2 Slack Status


Kitura-NIO is a SwiftNIO based networking library for Kitura. Kitura-NIO adopts the same API as KituraNet, making the transition from KituraNet to Kitura-NIO seamless. While Kitura-NIO shares some code with Kitura-Net, the core comprising of HTTPServer, ClientRequest/ClientResponse and TLS support have been implemented using SwiftNIO. Kitura-NIO uses NIOSSL for TLS support.

We expect most of our users to require higher level concepts such as routing, templates and middleware. These are not provided in Kitura-NIO. If you want to use those facilities you should be coding at the Kitura level, for this please see the Kitura project. Kitura-NIO, like Kitura-net, underpins Kitura which offers a higher abstraction level to users.

Kitura-NIO 2 has been tested with Swift 5. If you are using Swift 4, please use Kitura-NIO 1. See the release history for details.


  • Port Listening
  • HTTP Server support (request and response)
  • Basic HTTP client support

Using Kitura-NIO

With Kitura 2.5 and future releases, to run on top of Kitura-NIO (instead of Kitura-Net) all you need to do is set an environment variable called KITURA_NIO before building your Kitura application:

    export KITURA_NIO=1 && swift build

If you have already built your Kitura application using Kitura-Net and want to switch to using KITURA_NIO, you need to update the package before building:

    export KITURA_NIO=1 && swift package update && swift build

Using the environment variable we make sure that only one out of Kitura-NIO and Kitura-Net is linked into the final binary.

Please note that though Kitura-NIO has its own GitHub repository, the package name is KituraNet. This is because the Kitura-NIO and Kitura-Net are expected to provide identical APIs, and it makes sense if they share the package name too.

Getting Started

Visit www.kitura.io for reference documentation.

Contributing to Kitura-NIO

We'd be more than happy to receive bug reports, enhancement requests and pull requests!

  1. Clone this repository.

$ git clone https://github.com/IBM-Swift/Kitura-NIO && cd Kitura-NIO

  1. Build and run tests.

$ swift test

You may also want to run the tests in parallel: $ swift test --parallel

In some Linux environments, a low open file limit could cause test failures. See this.


We'd really love to hear feedback from you.

Join the Kitura on Swift Forums or our Slack to meet the team!


This library is licensed under Apache 2.0. The full license text is available in LICENSE.


Stars: 28
Help us keep the lights on


2.2.0 - Jul 29, 2019

What's new

  • A nasty race condtion related to WebSocket upgrade has been removed (#217)
  • ClientRequest: HTTP credentials will no longer be included in the ClientRequest.url property. This is a small behaviour change (#208)
  • The creation of HTTPServerRequest objects is now permissible only on the EventLoop on which the underlying HTTP request arrived (#215)
  • ClientRequest: new request headers added for parity with Kitura-net (#213)
  • ClientResponse.status is now updated to reflect the value of ClientResponse.statusCode (#214)

2.1.1 - Jun 5, 2019

What's new

  • Falling back to building HTTPServerRequest.urlURL using String concatenation instead of URLComponents. This also includes a change to ClientRequest that makes sure we don't percent-encode a URL string twice. (https://github.com/IBM-Swift/Kitura-NIO/pull/199)

2.1.0 - May 24, 2019

What's new

  • Allow Kitura-NIO to only listen on one network address (#205). Kitura listens on every available address/interface. This feature allows Kitura to listen on only on interface (only one network address)

2.0.5 - May 17, 2019

What's new

  • Upgrade to swift-nio 2.1 (#204)

2.0.4 - May 14, 2019

What's new

  • Fix for a WebSocket upgrade failure in Safari based clients(https://github.com/IBM-Swift/Kitura-NIO/pull/203)