Is there a way for me to add properties to a LoggingEvent without the user
doing anything out of the ordinary. Maybe it's even best to assume an existing
application which is using log4net. I would like to take this existing log4net
application and without them changing any code, configuration changes are ok, I
would like to add properties to each LoggingEvent which is created from their
log statements like:
logger.Error();
logger.Info();
logger.Debug();
etc.
such that I could use the PropertyFilter filter to filter out events? I want
to set a property based on the level of the event. I could of course use the
LevelRangeFilter but in other cases I'm using the PropertyFilter and was
figuring it might be nice to do it the same for all events.
This other case where I'm using the PropertyFilter is for new events we've
introduced. These are what we call "compliance" and "business" events. We
originally introduced a "compliance" event and at that time I introduced a
custom level for that. However, I'm trying to move away from defining custom
levels and instead use a property on the event to distinguish its "category".
For these new events which don't fit nicely into the level gradient I've
introduced a method for developers to use to log them called LogEvent(). They
will pass in their logger, the category of the event, and the event. In this
scenario it's easy for me to set properties on the LoggingEvent. However, for
what we call the diagnostic events, those that are logged using the methods
exposed by log4net, we don't want them to have to do anything different than
they were doing. If they want to log an error they would still use:
logger.Error("this is my error");
or a warning:
logger.Warn("this is my warning");
etc.
Ideally I would like to set the "category" on those events also so that by the
time they make it to the appender it has this "category" property. Is there a
way to do that?
Thanks,
Nick
________________________________
From: Dominik Psenner <dpsen...@gmail.com>
Sent: Sunday, October 23, 2016 9:18 AM
To: Log4NET User
Subject: Re: Injecting properties into LoggingEvent
Sorry, I cannot grasp your requirements. Please try to explain your usecase
better in a way that gives the document some kind of structure.
On 23 Oct 2016 12:02 a.m., "Nicholas Duane"
<nic...@msn.com<mailto:nic...@msn.com>> wrote:
Thank you for the suggestions.
We are already logging complex objects in many cases. We have the notion of a
compliance event. That's basically a map (IDictionary<string, object>). We're
now adding business events. However, even with these "complex" events I don't
want the map to contain the category, at least not at event creation time. I
see an event as just a collection of properties. The act of logging it at a
certain level or category is what assigns the severity or category. For
example:
logger.Warn("this is my warning message");
logger.Error("this is my error message");
logger.Info("this is my info message");
In each of those cases if we assume the event is the message itself, there is
no criticality associated with that event. It's the act of logging that
defines the event's criticality. I want the same to be true for the category.
I believe I have this working fine for our "complex" events which don't fit
into the Level gradient. I expose a LogEvent() method which logs at the
Emergency level as I showed in the code I included in the previous thread.
However, we also need to capture diagnostic events, ones that are logged via
the logging framework's methods:
logger.Error(...);
logger.Warn(...);
What I am hoping to do is hook in some of my code and generate one of our
complex events each time the logging framework logs an event and will map the
level to one of our categories. I can imagine that this might be possible if I
somehow wrap a logger, but as I mentioned I don't want the user to have to call
anything special at startup to hook up that wrapping. I was hoping there would
be a way for me to hook myself in via configuration. I'm ok with giving them a
configuration file they need to use but I don't want them to have to change any
existing code them may have.
By the way, we did generate a custom log level for our compliance event.
However I'm trying to move away from that as it was point out that our events
don't fit well within the level gradient. So the new code for logging a
compliance event does not use that level. Both the compliance and business
event would be logged at the Emergency level. I would use the category
property to differentiate them. Similar, I guess, to log4j2's Markers.
Thanks,
Nick
________________________________
From: Dominik Psenner <dpsen...@gmail.com<mailto:dpsen...@gmail.com>>
Sent: Saturday, October 22, 2016 1:29 PM
To: Log4NET User
Subject: Re: Injecting properties into LoggingEvent
What I am proposing here are a mere ideas that will need further investigation.
I have not tried any of these ideas. You will have to prioritize these ideas
based on your requirements.
A. Implement an extension class for the ILog interface
B. Implement a custom ILog interface implementation and a LoggerFactory.
C. Define custom loglevels
D. Use thread context properties altogether with custom format layouts
E. Log "complex" classes that hold your category information and find a way to
format them
There might be more things that you could do..
On 22 Oct 2016 5:31 p.m., "Nicholas Duane"
<nic...@msn.com<mailto:nic...@msn.com>> wrote:
Is there a way for me to inject properties into a LoggingEvent? I'm trying to
accomplish this without the user (of log4net) doing anything special. The only
thing I could think of was wrapping loggers, and while I'm not against doing
that it would have to be done via configuration as I don't want the user to
have to do it programmatically. Is there any way for me to inject a logger
wrapper via configuration?
The reason I'm looking to do this is that I would like to set a property on the
LoggingEvent to use for filtering. This property would be determined based on
the level property. I could simply use the level property for filtering, but I
have other events which I generate which are all logged at the Emergency level
but have a different value for this property so for them I'm using this
property for filtering. I don't have the same issue with these other events
because they are logged via an extension method I provided on the ILog
interface:
public static class Logging
{
public static void LogEvent(this ILog logger, Category category, IEvent
evnt)
{
if ((category != null) && (evnt != null))
{
evnt.SetCategory(category.Name);
LoggingEvent le = new LoggingEvent(null, logger.Logger.Respository,
logger.Logger.Name<http://logger.Logger.Name>,
Level.Emergency, evnt, null);
le.Properties["category"] = category.Name;
logger.Logger.Log(le);
}
}
}
So for instance when a user does the following:
logger.Error("this is my error message");
or
logger.Warn("this is my warning message");
or
logger.Info("this is my info message");
I would like to set the property "category" on the LoggingEvent to
"criticalDiagnostic". When they do:
logger.Debug("this is my debug message");
or
logger.Trace("this is my trace message");
I would like to set the property "category" on the LoggingEvent to
"noncriticalDiagnostic". Any way for me to do that automagically?
I also posted this at:
http://stackoverflow.com/questions/40187597/injecting-properties-into-log4nets-loggingevent
Thanks,
Nick
