serilog multiple instance per functionality

Question

While I have a general purpose logger for errors, exceptions etc that use rolling file sink to log stuff to my-{date}.log.

However, I need another instance for audit to audit-{date}.log and another instance to write perf info to perf-{date}.log.

How do I create multiple instances of serilog with different configuration or sink?

Interesting question, would [Expression-based event filtering](https://github.com/serilog/serilog-filters-expressions) help? — Mark G, Jul 24 '18 at 18:32
Take a look at Christo's answer https://stackoverflow.com/questions/51213779/can-i-log-to-separate-files-using-serilog — John81, Feb 27 '19 at 14:22

score 0 · Answer 1 · answered Jul 24 '18 at 18:34

You can do this like following:

        var loggerConfiguration = new LoggerConfiguration()
                       .MinimumLevel.Verbose()
                       .Enrich.FromLogContext();
        var fileBasePath = "<base log path>";
        loggerConfiguration
            .WriteTo.Console()
            .WriteTo.RollingFile(fileBasePath + "log-info-{Date}.txt")
            .WriteTo.Logger(fileLogger => fileLogger
                    .MinimumLevel.Error()
                    .WriteTo.RollingFile(fileBasePath + "log-error-{Date}.txt"))
            .WriteTo.Logger(fileLogger => fileLogger
                    .Filter.ByIncludingOnly(x =>
                          x.Level == LogEventLevel.Information &&
                          x.Properties.ContainsKey("<Audit Key>"))
                    .WriteTo.RollingFile(fileBasePath + "log-audit-{Date}.txt"));
        Log.Logger = loggerConfiguration.CreateLogger();

Note: Audit Key is a key which used in audit log

I don't want to do filtering.I need a new instance that respects to its own configuration. — DarthVader, Jul 25 '18 at 07:00

score 0 · Answer 2 · answered Nov 10 '18 at 20:01

I assume you would need different interface name to write audit and perf data (to be injected to your main business code). If that's the case just implement your IAudit, IPerfData with a new Serilog instance which you can totally customize where/how you save the log.

serilog multiple instance per functionality

2 Answers2