Nlog: Semi Dynamic Routing Rules in code

[ssteiner]

I would like to replicate the example given in the "Semi Dynamic Routing Rules" section of this page: https://github.com/nlog/nlog/wiki/Filtering-log-messages

Nlog.Config.LoggingRule uses Nlog.LogLevel for MinLevel and MaxLevel, so how can I use a configuration variable to dynamically set the minLevel?

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[snakefoot]

Was thinking that people who used the config-api from code, didn't need the help of dynamic-layout-logic. Both because of the overhead, but also because the runtime validation of the Layout-result makes it more error-prone.

Instead I recommend that you just create the LoggingRule using the constructor where you can provide a ruleName. Then you can lookup the LoggingRule at later point and modify it like you want (See LoggingConfiguration.FindRuleByName).

P.S. Remember to call ReconfigureExistingLoggers after changing LoggingRules of the active Configuration,.

[snakefoot]

Alternative you can use NLog.Filters.WhenMethodFilter and implement your filtering there.

c# config.LoggingRules.Last().Filters.Add(new WhenMethodFilter(logEvent => ShouldIgnoreLogEvent(logEvent) ? FilterResult.Ignore : FilterResult.Log));

No need to call ReconfigureExistingLoggers and it is fully dynamic (not just semi).

[snakefoot]

Have updated the Wiki for you:

https://github.com/NLog/NLog/wiki/Filtering-log-messages

[ssteiner]

@snakefoot: I needed dynamic adaptation of the minimum log level. In my first attempt, I found the LogginRule.IsLoggingEnabledForLevel and LoggingRule.EnableLoggingForLevel methods, but I overlooked the method to set the minLevel (SetLoggingLevels). So my solution was somewhat clunky.
I had to make a second pass over the code and then discovered the SetLoggingLevels - so in the end, my solution looks pretty much as you suggested in your first post.

Thanks for the additional approach - that looks pretty much like the idea I first had (but didn't find the methods that would enable me to do so.).