Serilog.Enrichers.HttpContext

Enriches Serilog events with client IP, RequestBody, RequestQuery, HTTP request headers and memory usage. Correlation Id can be added via WithRequestHeader("X-Correlation-Id", "CorrelationId").

Supported frameworks: .NET Standard 2.1, .NET 6, .NET 7, .NET 8, .NET 9, .NET 10

Install the Serilog.Enrichers.HttpContext NuGet package

Install-Package Serilog.Enrichers.HttpContext

or

dotnet add package Serilog.Enrichers.HttpContext

Apply the enricher to your LoggerConfiguration in code:

Log.Logger = new LoggerConfiguration()
    .Enrich.WithClientIp()
    .Enrich.WithMemoryUsage()
    .Enrich.WithMemoryUsageExact()
    .Enrich.WithRequestBody()
    .Enrich.WithRequestQuery()
    .Enrich.WithRequestHeader("Header-Name1")
    // ...other configuration...
    .CreateLogger();

or in appsettings.json file (requires Serilog.Settings.Configuration or Serilog.AspNetCore):

{
  "Serilog": {
    "MinimumLevel": "Verbose",
    "Using":  [ "Serilog.Enrichers.HttpContext" ],
    "Enrich": [
      "WithClientIp",
      "WithMemoryUsage",
      "WithMemoryUsageExact",
      "WithRequestBody",
      "WithRequestQuery",
      {
        "Name": "WithRequestHeader",
        "Args": {
          "headerName": "X-Correlation-Id",
          "propertyName": "CorrelationId"
        }
      },
      {
        "Name": "WithRequestHeader",
        "Args": { "headerName": "User-Agent" }
      }
    ],
    "WriteTo": [
      { "Name": "Console" }
    ]
  }
}

---

Enricher Configuration

WithClientIp

Adds the ClientIp property — client IP address. By default uses "x-forwarded-for" header. When behind a proxy, uses the configured header to determine the real IP. Returns "unknown" when the IP cannot be determined.

Parameter	Type	Default	Description
headerName	string	"x-forwarded-for"	Proxy header name containing the IP address

Code:

.Enrich.WithClientIp()
.Enrich.WithClientIp(headerName: "CF-Connecting-IP")

appsettings.json:

"WithClientIp"

or with parameters:

{
  "Name": "WithClientIp",
  "Args": { "headerName": "CF-Connecting-IP" }
}

Full example for custom proxy header:

{
  "Serilog": {
    "MinimumLevel": "Verbose",
    "Using":  [ "Serilog.Enrichers.HttpContext" ],
    "Enrich": [
      {
        "Name": "WithClientIp",
        "Args": { "headerName": "CF-Connecting-IP" }
      }
    ],
    "WriteTo": [ { "Name": "Console" } ]
  }
}

WithMemoryUsage

Adds the MemoryUsage property — process memory usage in bytes. Works in any context (does not require HTTP request).

Code:

.Enrich.WithMemoryUsage()

appsettings.json:

"WithMemoryUsage"

WithMemoryUsageExact

Adds the MemoryUsageExact property — memory increase since the start of the request (in bytes).

Required: You must add app.UseSerilogMemoryUsageExact() middleware to the pipeline. Place it early, before request handlers (e.g. MapGet, MapControllers).

Enricher registration

Code:

.Enrich.WithMemoryUsageExact()

appsettings.json:

"WithMemoryUsageExact"

Middleware registration

Program.cs (minimal hosting):

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddHttpContextAccessor();
builder.Host.UseSerilog((context, services, configuration) => configuration
    .ReadFrom.Configuration(context.Configuration)
    .ReadFrom.Services(services));

var app = builder.Build();
app.UseSerilogMemoryUsageExact();
app.MapGet("/", () => "Hello");
app.Run();

Startup.cs (in Configure method):

public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerFactory)
{
    loggerFactory.AddSerilog();
    app.UseSerilogMemoryUsageExact();
    app.UseRouting();
    app.UseEndpoints(endpoints => { /* ... */ });
}

WithRequestBody

Adds the RequestBody property — HTTP request body. Note: If controllers or model binding read the body before logging, add middleware at the start of the pipeline to enable buffering:

app.Use(async (context, next) =>
{
    context.Request.EnableBuffering();
    await next();
});

Code:

.Enrich.WithRequestBody()

appsettings.json:

"WithRequestBody"

WithRequestQuery

Adds the RequestQuery property — HTTP request query string.

Code:

.Enrich.WithRequestQuery()

appsettings.json:

"WithRequestQuery"

WithRequestHeader

You can use multiple WithRequestHeader to log different request headers. WithRequestHeader accepts two parameters: the first parameter headerName is the header name to log, and the second parameter propertyName is the log property name.

Parameter	Type	Required	Description
headerName	string	yes	HTTP header name
propertyName	string	no	Log property name (if not specified — headerName without hyphens)

When the header is absent, the property value is null.

Code:

.Enrich.WithRequestHeader("User-Agent")
.Enrich.WithRequestHeader(headerName: "Content-Length", propertyName: "RequestLength")
.Enrich.WithRequestHeader("X-Correlation-Id", "CorrelationId")

appsettings.json:

{
  "Name": "WithRequestHeader",
  "Args": { "headerName": "User-Agent" }
}

or with custom property name:

{
  "Name": "WithRequestHeader",
  "Args": {
    "headerName": "X-Correlation-Id",
    "propertyName": "CorrelationId"
  }
}

Full example with multiple headers:

{
  "Serilog": {
    "MinimumLevel": "Verbose",
    "Using": [ "Serilog.Enrichers.HttpContext" ],
    "Enrich": [
      { "Name": "WithRequestHeader", "Args": { "headerName": "User-Agent" } },
      { "Name": "WithRequestHeader", "Args": { "headerName": "header-name" } },
      {
        "Name": "WithRequestHeader",
        "Args": {
          "headerName": "Content-Length",
          "propertyName": "RequestLength"
        }
      }
    ],
    "WriteTo": [ { "Name": "Console" } ]
  }
}

Note

To include logged headers in OutputTemplate, the header name without - should be used if you haven't set the log property name. For example, if the header name is User-Agent, you should use UserAgent.

Log.Logger = new LoggerConfiguration()
    .MinimumLevel.Debug()
    .Enrich.WithRequestHeader("User-Agent")
    .WriteTo.Console(outputTemplate: "[{Timestamp:HH:mm:ss}] {Level:u3} {UserAgent} {Message:lj}{NewLine}{Exception}")

---

Installing into an ASP.NET Core Web Application

You need to register the IHttpContextAccessor singleton so the enrichers have access to the requests HttpContext. Without it, WithClientIp, WithRequestBody, WithRequestQuery, WithRequestHeader, and WithMemoryUsageExact will not add properties when logging outside a request context or when HttpContext is unavailable.

If you use WithMemoryUsageExact, you must add the app.UseSerilogMemoryUsageExact() middleware early in the pipeline (before request handlers) to capture memory at the start of each request.

This is what your Startup class should contain in order for this enricher to work as expected:

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Serilog;

namespace MyWebApp
{
    public class Startup
    {
        public Startup()
        {
            Log.Logger = new LoggerConfiguration()
                .MinimumLevel.Verbose()
                .WriteTo.Console(outputTemplate: "[{Timestamp:HH:mm:ss}] {Level:u3} Client IP: {ClientIp} Correlation Id: {CorrelationId} header-name: {headername} {Message:lj}{NewLine}{Exception}")
                .Enrich.WithClientIp()
                .Enrich.WithMemoryUsage()
                .Enrich.WithMemoryUsageExact()
                .Enrich.WithRequestBody()
                .Enrich.WithRequestQuery()
                .Enrich.WithRequestHeader("header-name")
                .Enrich.WithRequestHeader("another-header-name", "AnotherHeaderNameNewName")
                .CreateLogger();
        }

        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            // ...
            services.AddHttpContextAccessor();
            // ...
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILoggerFactory loggerFactory)
        {
            // ...
            loggerFactory.AddSerilog();
            app.UseSerilogMemoryUsageExact();  // Required for WithMemoryUsageExact enricher
            // ...
        }
    }
}

For minimal hosting (Program.cs with WebApplication):

builder.Services.AddHttpContextAccessor();

builder.Host.UseSerilog((context, services, configuration) => configuration
    .ReadFrom.Configuration(context.Configuration)
    .ReadFrom.Services(services));

var app = builder.Build();
// ...
app.UseSerilogMemoryUsageExact();  // Required for WithMemoryUsageExact enricher
// ...
app.Run();