swift-nio

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# SwiftNIO

SwiftNIO is a cross-platform asynchronous event-driven network application framework
for rapid development of maintainable high performance protocol servers & clients.

It's like [Netty](https://netty.io), but written for Swift.

### Repository organization

The SwiftNIO project is split across multiple repositories:

Repository | NIO 2
--- | ---
[https://github.com/apple/swift-nio][repo-nio] <br> SwiftNIO core | `from: "2.0.0"`
[https://github.com/apple/swift-nio-ssl][repo-nio-ssl] <br> TLS (SSL) support | `from: "2.0.0"`
[https://github.com/apple/swift-nio-http2][repo-nio-http2]<br> HTTP/2 support | `from: "1.0.0"`
[https://github.com/apple/swift-nio-extras][repo-nio-extras] <br>useful additions around SwiftNIO | `from: "1.0.0"`
[https://github.com/apple/swift-nio-transport-services][repo-nio-transport-services] <br> first-class support for macOS, iOS, tvOS, and watchOS | `from: "1.0.0"`
[https://github.com/apple/swift-nio-ssh][repo-nio-ssh] <br> SSH support | `.upToNextMinor(from: "0.2.0")`
[https://github.com/apple/swift-nio-quic][repo-nio-quic] <br> QUIC support (in active development) | `branch: "main"`
[https://github.com/apple/swift-nio-http3][repo-nio-http3] <br> HTTP/3 support (in active development) | `branch: "main"`

Within this repository we have a number of products that provide different functionality. This package contains the following products:

- `NIO`. This is an umbrella module exporting `NIOCore`, `NIOEmbedded` and `NIOPosix`.
- `NIOCore`. This provides the core abstractions and types for using SwiftNIO (see ["Conceptual Overview"](#conceptual-overview) for more details). Most NIO extension projects that provide things like new [`EventLoop`s][el] and [`Channel`s][c] or new protocol implementations should only need to depend on `NIOCore`.
- `NIOPosix`. This provides the primary [`EventLoopGroup`], [`EventLoop`][el], and [`Channel`s][c] for use on POSIX-based systems. This is our high performance core I/O layer. In general, this should only be imported by projects that plan to do some actual I/O, such as high-level protocol implementations or applications.
- `NIOEmbedded`. This provides [`EmbeddedChannel`][ec] and [`EmbeddedEventLoop`][eel], implementations of the `NIOCore` abstractions that provide fine-grained control over their execution. These are most often used for testing, but can also be used to drive protocol implementations in a way that is decoupled from networking altogether.
- `NIOConcurrencyHelpers`. This provides a few low-level concurrency primitives that are used by NIO implementations, such as locks and atomics.
- `NIOFoundationCompat`. This extends a number of NIO types for better interoperation with Foundation data types. If you are working with Foundation data types such as `Data`, you should import this.
- `NIOTLS`. This provides a few common a