A code file from the blog article about dumping any request in ASP.NET Core 2.0

Blog_RequestDump_AspNetCore2.cs

using System;
using System.IO;
using System.Linq;
using System.Text;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Routing;
using Microsoft.Extensions.DependencyInjection;

namespace RequestDump
{
    public class Startup
    {
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddRouting();
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            var routeHandler = new RouteHandler(
                context =>
                {
                    var path = Dump(context);

                    // Write the response to the user so he can see that request was dumped.
                    return context.Response.WriteAsync($"Request saved to '{path}'.");
                });

            var routeBuilder = new RouteBuilder(app, routeHandler);
            routeBuilder.MapRoute("Dump Any Request", "{*.}");

            var routes = routeBuilder.Build();
            app.UseRouter(routes);
        }

        private static string Dump(HttpContext context)
        {
            var httpMethod = context.Request.Method;

            // Get the full route of the request to use it as a part of dump file.
            var route = context.GetRouteData().Values["."];

            // Create file name.
            var fileName = EscapeInvalidChars($"{httpMethod}_{DateTime.Now:yyMMdd_HHmmss}_{route}.txt");
            var path = Path.Combine(@"C:\Dump", fileName);

            using (var reader = new StreamReader(context.Request.Body))
            {
                // Read the full body of the request and save it to file.
                var body = reader.ReadToEnd();
                File.WriteAllText(path, body);
            }

            return path;
        }

        private static string EscapeInvalidChars(string invalidFileName, char escapeChar = '_')
        {
            var builder = new StringBuilder(invalidFileName);
            var invalidChars = Path.GetInvalidFileNameChars().Concat(Path.GetInvalidPathChars());

            foreach (var c in invalidChars)
            {
                builder.Replace(c, escapeChar);
            }

            return builder.ToString();
        }
    }
}