How can you make two different NLog targets with same date inside? - asp.net-core

Question

I have the following two targets defined in NLog.config inside my ASP.NET Core project:
<targets>
<target name="MyApp" xsi:type="File"
fileName="${specialfolder:folder=ApplicationData}/MyApp/${date:format=yyyyMMdd_HHmmss:cached=true}_MyApp.log"
layout="${longdate}|${level:uppercase=true}|${logger}|${message}"
deleteOldFileOnStartup="false"/>
<target name="MyAppAll" xsi:type="File"
fileName="${specialfolder:folder=ApplicationData}/MyApp/${date:format=yyyyMMdd_HHmmss:cached=true}_MyApp.log"
layout="${longdate}|${level:uppercase=true}|${logger}|${message}"
deleteOldFileOnStartup="false"/>
</targets>
MyApp target logs all my logs from the app while MyAppAll includes some framework logs as well.
I am trying to get the NLog to create two log files that have the same timestamp but what I have observed is that MyAppAll will be created immediately on app start since this is the time framework logs start while MyApp will only be created once I send request to API and the result is that I have two files with different dates.
Any ideas on how to solve this?

Answer 1

You can use ${processinfo:StartTime}:
<targets>
<target name="MyApp" xsi:type="File"
fileName="${specialfolder:folder=ApplicationData}/MyApp/${processinfo:StartTime:format=yyyyMMdd_HHmmss:cached=true}_MyApp.log"
layout="${longdate}|${level:uppercase=true}|${logger}|${message}" />
<target name="MyAppAll" xsi:type="File"
fileName="${specialfolder:folder=ApplicationData}/MyApp/${processinfo:StartTime:format=yyyyMMdd_HHmmss:cached=true}_MyApp.log"
layout="${longdate}|${level:uppercase=true}|${logger}|${message}" />
</targets>
See also: https://github.com/NLog/NLog/wiki/ProcessInfo-Layout-Renderer
Notice having 2 file-targets sharing the same filename is not recommended. Forexample with NLog 5 where KeepFileOpen=true by default, then one will stop working.