nng.NET/NETCore

.NET bindings to NNG:

NNG, like its predecessors nanomsg (and to some extent ZeroMQ), is a lightweight, broker-less library, offering a simple API to solve common recurring messaging problems, such as publish/subscribe, RPC-style request/reply, or service discovery. The API frees the programmer from worrying about details like connection management, retries, and other common considerations, so that they can focus on the application instead of the plumbing.

Status:

Using latest NNG release.

For list of missing APIs/features see issues (is:open label:enhancement).

Goals of nng.NET:

• Async first: async/await access to nng_aio and nng_ctx
• Native layer: P/Invoke in separate files/namespace. Don't like our high-level OO wrapper? Re-use the pinvoke and make your own. Also makes cross-platform-friendly pinvoke easier.
• Tests as Documentation: xUnit unit/integration tests in "plain" C# similar to application code
• Modern .NET: C# 7.3 and using dotnet and targeting .NET Standard and .NET Core/5 from the start
• Safety: Minimal exceptions and null, type system avoids many runtime errors at compile time.
• Simple: Shallow class hierarchy (more composition than inheritance), idiomatic C# similar to original native code when reasonable.

Usage

Supports projects targeting:

• .NET 5
• .NET Core App 1.0+
• .NET Standard 1.5+
  • SuppressUnmanagedCodeSecurity is used with .NET Standard 2.0+ for improved PInvoke performance

Supported platforms:

• Windows Vista or later 32/64-bit (built on Windows Server 2019)
• macOS/OSX 10.?+ 64-bit (built on 10.15)
• Linux x86_64, ARM32/armv7l, ARM64/aarch64 (built on Debian 10/Buster)

Should be easy to add others that are supported by both .NET Core/5 and NNG.

After installing the package and building, your output folder should have runtimes/ directory containing native binaries.

Use NngLoadContext (or your own AssemblyLoadContext) to load the appropriate native library and use NNG:

var path = Path.GetDirectoryName(typeof(Program).Assembly.Location);
var ctx = new nng.NngLoadContext(path);
var factory = nng.NngLoadContext.Init(ctx);
// Use factory...

See tests/ and examples/ for usage examples.

Build & Run

You should be able to build nng.NET for/on any platform supported by .NET Core/5:

1. Build: dotnet build
2. Run: dotnet run or dotnet test tests

You should be able to build the NNG native shared library for any platform supported by NNG. See scripts/build_nng.ps1 for details, but in general:

1. Download/clone NNG source
2. On Windows, create Command Prompt suitable for Visual Studio:
   • Run x64 Visual Studio Developer Command Prompt to create a 64-bit library (or x86 for 32-bit)
   • OR, run vcvars64.bat in cmd.exe (or vcvars32.bat)
3. Run:

   mkdir build && cd build
   cmake -DBUILD_SHARED_LIBS=ON ..
   cmake --build .

4. Copy library to appropriate directory (i.e. nng.NET/runtimes/XXX/native/)