W4k.AspNetCore.Correlator

Correlator helps you with handling correlation ID (also "request ID"): reading, generating new one and forwarding to subsequent requests.

Correlation ID is sent within HTTP headers. If header is not set, Correlator will happily generate new one for you.

Apart from accepting or generating correlation ID, it is also possible to return correlation ID back to caller, so in case when correlation ID is generated, caller is aware of that value.

To forward correlation ID to subsequent request, it is necessary to use designated HTTP message handler, see examples below.

W3 Trace Context and .NET

Be aware that Trace Context is not supported, Correlator helps you with simple non-standard headers.

Distributed tracing and trace context is built in .NET, You can get more insights from article: .NET distributed tracing.

Basic usage

Startup class

var builder = WebApplication.CreateBuilder(args); builder.Services.AddDefaultCorrelator(); var app = builder.Build(); // register as first middleware // (or as soon as possible to benefit from having correlation ID) app.UseCorrelator(); // ... app.Run();

Accessing correlation ID

Correlation ID of current request is available via ICorrelationContextAccessor.CorrelationContext: