${aspnet-request-posted-body} produces empty log

[Tabgyn]

Type:

• Bug

NLog version: 4.7.2

NLog.Web version: 4.9.2

Platform: .Net 4.5

Current NLog config

<?xml version="1.0" encoding="utf-8" ?>
<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      throwConfigExceptions="true">
  <targets>
    <target name="logfile" xsi:type="File" fileName="file.txt" layout="${aspnet-request}"/>    
  </targets>

  <rules>
    <logger name="*" minlevel="Error" writeTo="logfile"/>
  </rules>
</nlog>

C# Controller

using NLog;
using System;
using System.Web.Mvc;

namespace NLogSample.Controllers
{
    public class HomeController : Controller
    {
        private static readonly Logger Logger = LogManager.GetCurrentClassLogger();
        public ActionResult Index()
        {
            ViewBag.Title = "Home Page";

            return View();
        }

        public ActionResult Exception(string value, string body)
        {
            try
            {
                if(string.IsNullOrEmpty(value))
                    throw new ArgumentNullException(nameof(value));
            }
            catch (Exception ex)
            {
                Logger.Error(ex, ex.Message);
                throw;
            }

            return RedirectToAction("Index");
        }
    }
}

• What is the current result?
  ${aspnet-request} logs nothing

• What is the expected result?
  Request to be logged

• Did you checked the Internal log?
  Yes. The internal log does not have errors.

• Please post full exception details (message, stacktrace, inner exceptions)

Value cannot be null.
Parameter name: value
   at NLogSample.Controllers.HomeController.Exception(String value, String body) in C:\Users\Tiago\source\repos\NLogSample\NLogSample\Controllers\HomeController.cs:line 30
   at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
   at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
   at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<>c.<BeginInvokeSynchronousActionMethod>b__9_0(IAsyncResult asyncResult, ActionInvocation innerInvokeState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass11_0.<InvokeActionMethodFilterAsynchronouslyRecursive>b__0()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass11_2.<InvokeActionMethodFilterAsynchronouslyRecursive>b__2()

• Are there any workarounds?
  No

[snakefoot]

The documentation says that you need to specify what part of the AspNet-Request-HttpContext that you want to output (cookie, header, item, form, queryString):

https://github.com/NLog/NLog/wiki/AspNetRequest-layout-renderer

You will also notice that for ASP.NET Core, then it has been split into several layoutrenderers.

Maybe try this instead:

layout="${aspnet-request-url:includeQueryString=true}

See also: https://github.com/NLog/NLog/wiki/AspNetRequest-Url-Layout-Renderer

[Tabgyn]

Thank you! But now I'm trying to use ${aspnet-request-posted-body} and it doesn't show anything".

[snakefoot]

Sounds like a different issue. Maybe duplicate of #556

[Tabgyn]

I saw this issue, trying to work on a workaround since in my case it is Framework 4.5 and not Core

[snakefoot]

@Tabgyn Have you checked the NLog InternalLogger ? https://github.com/NLog/NLog/wiki/Logging-troubleshooting

[Tabgyn]

Yes

<nlog xmlns="http://www.nlog-project.org/schemas/NLog.xsd"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      throwConfigExceptions="true"
      internalLogFile="c:\log.txt" internalLogLevel="Trace">
...

I don't see errors
log.txt

[snakefoot]

Guess you have to start debugging, and figure out why NLog fails to extract anything from InputStream:

NLog.Web/src/Shared/LayoutRenderers/AspNetRequestPostedBody.cs

Lines 136 to 144 in 14ea99e

	private static Stream GetBodyStream(HttpRequest httpRequest)
	{
	#if !ASP_NET_CORE
	var body = httpRequest.InputStream;
	#else
	var body = httpRequest.Body;
	#endif
	return body;
	}

[snakefoot]

Thanks to @bakgerman now NLog.Web.AspNetCore v5.1 re-introduces ${aspnet-request-posted-body} with help from middleware:

app.UseMiddleware<NLog.Web.NLogRequestPostedBodyMiddleware>();

It is no longer necessary to explicit call context.Request.EnableBuffering(); as it is handled by the middleware.