Serilog–Filter expressions

One of the lesser known features inside Serilog is the support for filter expressions. This gives you a SQL like syntax to filter your log messages.

To enable this feature you have to install the Serilog.Filters.Expressions nuget package.

	var expr = "@Level = 'Information' and AppId is not null and Items[?] like 'C%'";
	Log.Logger = new LoggerConfiguration()
	.Enrich.WithProperty("AppId", 10)
	.Filter.ByIncludingOnly(expr)
	.WriteTo.Console()
	.CreateLogger();
	// Printed
	Log.Information("Cart contains {@Items}", new[] { "Tea", "Coffee" });
	Log.Information("Cart contains {@Items}", new[] { "Peanuts", "Chocolate" });
	// Not printed
	Log.Warning("Cart contains {@Items}", new[] { "Tea", "Coffee" });
	Log.Information("Cart contains {@Items}", new[] { "Apricots" });
	Log.CloseAndFlush();

view raw SerilogFilterDSL.cs hosted with ❤ by GitHub

More information: https://nblumhardt.com/2017/01/serilog-filtering-dsl/