Thank you for your help Rob. We identified that if one of the custom properties was not set at the point in time we're about to log a message (in our case not all log messages had a job id), that the value that was previously set for that thread was logged. This was the cause of our inconsistencies. So far we seem to be fine as long as we explicitly set all custom properties every log attempt including nullifying values if we don't expect one.
I'm still not 100% confident in our solution at this point but we've made some ground anyways. Thanks again for your thoughts. From: Rob Prouse [mailto:rob.pro...@ivara.com] Sent: Wednesday, September 01, 2010 1:42 PM To: Log4NET User Subject: RE: Custom Properties in an ASP.Net Web Application I took a quick look at the code and as far as I can see, the ThreadContext is taken out of the logging event when formatting the message which happens when it is being written. Therefore, I believe that if you use any appender deriving from the BufferingSkeletonAppender, then the ThreadContext will be wrong because the writing of the message happens on a different thread. So, I don't think you can use the ThreadContext. I assume you want to use properties so that you can have them as separate columns in the DB, otherwise you could just insert the values into the message. If that is the case, then the only solution I can think of is to download the source, copy the code from the ADO appender and create your own that does not derive from the buffering appender. Or, you could look at NLog and see if it meets your needs. Rob From: Gagne, Chris [mailto:cga...@ivey.uwo.ca] Sent: Wednesday, September 01, 2010 12:01 PM To: 'Log4NET User' Subject: RE: Custom Properties in an ASP.Net Web Application Yeah we're using the log4net.Appender.AdoNetAppender. From: Rob Prouse [mailto:rob.pro...@ivara.com] Sent: Wednesday, September 01, 2010 11:59 AM To: Log4NET User Subject: RE: Custom Properties in an ASP.Net Web Application For the common log appenders, the log is output synchronously with the log message, so it should be on the same thread, so it shouldn't be a problem. I am not sure of the behavior when you use an asynchronous appender (like the ADO appender), but it should be pulling the context out before it goes asynchronous. If it doesn't, then that would be a bug in log4net, but I would need to look at the code. What appender are you using? From: Gagne, Chris [mailto:cga...@ivey.uwo.ca] Sent: Wednesday, September 01, 2010 11:03 AM To: Log4NET User Subject: Custom Properties in an ASP.Net Web Application Here's our situation... We're adding debug messages to an ASP.Net web application that allows our users to apply for a job online. We have a custom properties and database fields created named JobPostingId and MemberId. Here's a small code snippet of our logging. ILog logger = LogManager.GetLogger(CONST_JOBPOSTINGS); if (logger.IsDebugEnabled) { log4net.ThreadContext.Properties[CONST_JOBPOSTINGID] = JobPostingId; log4net.ThreadContext.Properties[CONST_MEMBERID] = MemberId; logger.Debug(message); } We've noticed very inconsistent values for our custom properties. I suspect it has something to do with the context belonging to a thread and that same thread being reused by different web requests, therefore different users. Does anyone have suggestions for me on how I can capture user specific data into custom properties? Any thoughts or suggestions would be greatly appreciated.
