Added W3CExtendedLogLayout for writing W3C Extended Logs

[snakefoot]

Activate RequestMiddleware like this:

        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
           ...
           app.UseMiddleware<NLog.Web.RequestLoggingMiddleware>();
           ...
        }

Enable W3C Log-File like this in NLog.config:

<nlog throwConfigExceptions="true">
  <extensions>
    <add assembly="NLog.Web.AspNetCore"/>
  </extensions>
  <targets>
    <target file="w3c-file" filename="W3C-Requests.log">
         <layout type="W3CExtendedLogLayout"/>
    </target>
  </targets>
  <rules>
     <logger name="NLogRequestLogging" minLevel="Debug" writeTo="w3c-file" final="true" />
  </rules>
</nlog>

Available W3C log-parsers:

• https://github.com/jibedoubleve/log-reader
• https://support.microsoft.com/en-us/topic/log-parser-2-2-and-asp-net-37531636-1cf5-dc52-f12a-6a9252155631
• https://techcommunity.microsoft.com/t5/exchange-team-blog/introducing-log-parser-studio/ba-p/601131
• https://www.finalanalytics.com/products/httplogbrowser

[codecov-commenter]

Codecov Report

Merging #700 (0ec75b0) into master (b98cd07) will decrease coverage by 3%.
The diff coverage is 55%.

❗ Current head 0ec75b0 differs from pull request most recent head 43dda2d. Consider uploading reports for the commit 43dda2d to get more accurate results

@@          Coverage Diff           @@
##           master   #700    +/-   ##
======================================
- Coverage      64%    62%    -3%     
======================================
  Files          38     45     +7     
  Lines         581    780   +199     
  Branches      140    183    +43     
======================================
+ Hits          374    482   +108     
- Misses        157    235    +78     
- Partials       50     63    +13     

Impacted Files	Coverage Δ
...tRenderers/AspNetApplicationValueLayoutRenderer.cs	75% <ø> (ø)
src/NLog.Web/NLogRequestLoggingModule.cs	0% <0%> (ø)
...b/Targets/Wrappers/AspNetBufferingTargetWrapper.cs	0% <0%> (ø)
...LayoutRenderers/AspNetAppBasePathLayoutRenderer.cs	0% <ø> (ø)
.../Shared/LayoutRenderers/AspNetMvcActionRenderer.cs	40% <ø> (ø)
...red/LayoutRenderers/AspNetMvcControllerRenderer.cs	40% <ø> (ø)
...enderers/AspNetRequestContentTypeLayoutRenderer.cs	0% <ø> (ø)
...youtRenderers/AspNetRequestCookieLayoutRenderer.cs	87% <ø> (ø)
...LayoutRenderers/AspNetRequestFormLayoutRenderer.cs	94% <ø> (ø)
...outRenderers/AspNetRequestHeadersLayoutRenderer.cs	81% <ø> (ø)
... and 32 more

---

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[snakefoot]

Further optimizations can be made when NLog 5.0-preview2 is out:

• ScopeTiming - No Format specified renders TimeSpan.TotalMilliseconds NLog#4586 (Allow aspnet-request-duration work on NetCore2 with help from ${scopetiming})
• Layout - Render with StringBuilder target made public NLog#4584 (Reduce memory allocations)

[sonarqubecloud]

SonarCloud Quality Gate failed.   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
5 Code Smells

78.0% Coverage
0.0% Duplication

[snakefoot]

Created wiki-page: https://github.com/NLog/NLog/wiki/W3CExtendedLogLayout