Serilog Additional Properties with Exception logging

user_589333 0
Viewed 1412

I am using serilog with asp net core 3

It is setup and logging exceptions automatically - so i have no error handling to log the errors.

I was attempting to add extra context properties to logged items, and have added middleware to log these.

LogContext.PushProperty("Email", email);
LogContext.PushProperty("Url", url);

These are added if i manually log myself but any logs added automatically when an error occurs does not have these items added.

Any ideas?

NOTE: i have read this... https://blog.datalust.co/smart-logging-middleware-for-asp-net-core/ This is the closest i have found to working around the issue, but this catches the exception and manually logs it, which is a shame if this is the only way it can be done.

serilog asp.net-core
1 Answers

At first, LogContext is a stack; properties that are pushed onto the stack must be popped back off by disposing the object returned from PushProperty():

using (LogContext.PushProperty("Email", email))
using (LogContext.PushProperty("Url", url)){
   
    // middleware code
   ...
}

Otherwise, the behavior may be non-deterministic.

but any logs added automatically when an error occurs does not have these items added

I assume that error logging occurs outside of the scope, where these properties don't exist. In this case, try ThrowContextEnricher to enrich the exception log with properties from the original context where the exception was thrown.

// call it once on app startup
ThrowContextEnricher.EnsureInitialized();

...


// then each throwing will capture context,
// so you can enrich log in exception handler:
catch (Exception ex)
{
    using (LogContext.Push(new ThrowContextEnricher()))
    {
        Log.Error(ex, "Exception!"); 
    }
}

Or simply register ThrowContextEnricher globally at LoggerConfiguration (in this case ThrowContextEnricher.EnsureInitialized() is not required). So every exception log will be enriched:

Log.Logger = new LoggerConfiguration()
    .Enrich.With<ThrowContextEnricher>()
    .Enrich.FromLogContext()
    ...
    .CreateLogger();

Disclaimer: I am the author of that library, and I also left an example in this answer.

user_8434490
Related