Unable to redirect Console output (logging) to text (stdoutLogFile) file?

[bdcoder2]

Describe the bug

When trying to redirect Console output to a text file, the stdoutLogFile is created, but is always empty.

The following settings are present in the projects ( ASP.NET Core Web Application) web.config file:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <system.webServer>
    <handlers>
      <remove name="aspNetCore" />
      <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModuleV2" resourceType="Unspecified" />
    </handlers>
    <aspNetCore processPath="%LAUNCHER_PATH%" arguments="%LAUNCHER_ARGS%" stdoutLogEnabled="true" stdoutLogFile="D:\temp\website3_log" hostingModel="inprocess">
       <handlerSettings>
          <handlerSetting name="debugFile" value="D:\\temp\\website3_debug_log" />
          <handlerSetting name="debugLevel" value="FILE,INFO" />
       </handlerSettings>
      <environmentVariables>
        <environmentVariable name="ASPNETCORE_HTTPS_PORT" value="44383" />
        <environmentVariable name="COMPLUS_ForceENC" value="1" />
        <environmentVariable name="ASPNETCORE_ENVIRONMENT" value="Development" />
      </environmentVariables>
    </aspNetCore>
  </system.webServer>
</configuration>

The debugFile is created and log entries are present without issue.

The stdoutLogFile is created, but remains empty.

Questions:

• WHY is the stdoutLogFile always empty? It appears that when Console.WriteLine( "this should be in the log file" ) statements are executed within code, the WriteLine method is NOT redirecting output to the stdoutLogFile.

To Reproduce

Steps to reproduce the behavior:

1. Using Visual Studio
2. Click on "Create a new project"
3. Select ASP.NET Core Web Application -> Next
4. Enter project name, Location, Solution Name -> Create
5. Add web.config to the project and set the stdoutLogEnabled="true"
6. Set the stdoutLogFile attribute to the path of the log file.

Expected behavior

When Console.WriteLine() statements are executed, it is expected that the Console output is redirected to the stdoutLogFile file (or, at least one ASSUME's that would be the case -- can this be confirmed anywhere in the docs? -- I have yet to find anything!!).

Additional context

Also looking for details with regard to the schema of the following files:

• web.config - where do we find the complete schema? Where do we find the complete schema that explains all valid entries that may appear in this file and the effect of each entry.

• launchsettings.json - again, where do we find the complete schema that explains all valid entries that may appear in this file and the effect of each entry.

• This issue was raised within the documentation at: Console log redirection needs working example AspNetCore.Docs#15080

Finally, not sure if this would be possible, but a more consistent approach to Console logging (redirection) might be to include a "handler" for Console output, for example:

   <handlerSettings>
      <handlerSetting name="debugFile" value="D:\\temp\\website3_debug_log" />
      <handlerSetting name="debugLevel" value="FILE,INFO" />
      <handlerSetting name="consoleFile" value="D:\\temp\\website3_console_log" />
   </handlerSettings>

Adding a handler for Console output would be more consistent than the stdoutLogFile and stdoutLogEnabled attributes on the aspNetCore node.

[javiercn]

@bdcoder2 Thanks for contacting us.

@jkotalik @BillHiebert What's the appropriate way to achieve this? I remember there was a way to make this work, at least from within visual studio and IIS Express.

@bdcoder2 Search for a web.config file under the project file, likely inside the .vs folder and enable logging there.

[bdcoder2]

@javiercn @jkotalik @BillHiebert - Searched .vs folder (and all sub-folders) for web.config - no file found; did you imply to create web.config if not found?

After a week of trying to redirect console output to a text file (when running under debug within VS), I have since moved on (by creating my own ultra-simple logging class); further effort at this point does not seem worth it. I think it best to just close this issue and admit defeat -- or include a line within the docs that state:

Redirecting Console output to a text file while running a project within VS cannot be (easily) done; save your time (and sanity), and use your own logging method or a third party logging utility.

Thanks!

[jkotalik]

@bdcoder2 if you are running with IISExpress, do you see logs written to the Debug window in Visual Studio? StdoutLogFile + IISExpress isn't a common scenario; we could have broken it in 3.0 which we will verify but logs should show up in debug output.

If you run with full IIS, the options you provided above should work and output should be logged to a file.

[bdcoder2]

@jkotalik - No, any Console.WriteLine( "anything" ); statements DO NOT show in Debug output, but the output can be displayed via:

View -> Output -> Show output from -> Then I select "website3 - ASP.NET Core Web Server" from the pull-down menu.

Output from Console.WriteLine() statements are viewable when the above is selected.

To clarify, I was using Console.WriteLine() within my project (not ILogger) -- and was wanting to redirect Console output to a text file via settings in web.config

[jkotalik]

View -> Output -> Show output from -> Then I select "website3 - ASP.NET Core Web Server" from the pull-down menu.

Yes, that is what I meant (not debug). Apologies for getting the wrong menu.

To give a bit more detail, we have slight differences in how we handle console redirection between IIS and IISExpress. In IIS Express, we assume a console is attached, therefore wherever IISExpress logs is where we let it log (which is ASP.NET Core Web Server in Visual Studio). For IIS, there is no console, so the file should work correctly. @bdcoder2 can you confirm when you run with IIS, using stdOutLogFile?

@anurse there may be an issue with IISExpress + StdOutLog file being enabled; it looks like it does not log to the file.

[bdcoder2]

@jkotalik - No problem. I have not run the project on IIS as I am only learning .Net Core and haven't had the opportunity to publish the project yet. Your post makes complete sense though.

May I suggest the following (for all the other newbies like myself that may try this) - do not support Console output redirection for IISExpress - period.

Simply add a note to the docs with regard to the stdoutLogEnabled and stdoutLogFile attributes on the aspNetCore node within web.config. Something along the lines of:

Console output redirection is NOT supported when using IISExpress. To view Console output when using IISExpress, use the VS command: View -> Output -> Show output from -> Then select "{project-name} - ASP.NET Core Web Server" from the pull-down menu.

Had a note like the one above been present in the documentation, I would have been spared 4 days of pain and suffering! :)

Thanks again.

[analogrelay]

I'm not able to repro this. I did a new project, enabled the stdout log file and the debug file and both were written properly.

[bdcoder2]

@anurse - Can you please post your project somewhere on GitHub (make public)? Out of pure curiosity, I would like to see what differences exist between something that works, and my abomination that doesn't !

[analogrelay]

I don't have it handy as I didn't keep it around after updating. It was just File > New Project and then I set stdoutLogPath to .\logs\stdout and stdoutLogEnabled to true.

For the debug log, I copied your handlerSettings section and set the path to .\\logs\\debug. Both logs were produced when I F5'd.

[bdcoder2]

@nurse - sound like what happened to me -- but I directed stdoutLogPath and debug file paths to D:\temp\ -- the debug file had entries in it, but the stdoutLogPath file was always empty!! Was your file empty as well?

[analogrelay]

Nope, both my files had content in them. So the files were created in your case but were empty?

[bdcoder2]

@nurse - The output file path was set to: D:\temp\ (outside of project); and in my case, the
stdoutLogPath file is always empty. The debug file was not empty.