So in our project, we have enterprise library as our logger. Obviously, in production, we don't want to have our debug trace logging out all of the time, but we would like to be able to be able to turn on that debug trace without restarting the app pool, but I'm not quite sure how to go about it.
In the past, I'd have written something that would only log to the file if the file was present. So for instance, if I wanted to enable debug trace, I'd have the NOC drop a file in the log folder, then the next time the logger was invoked, it would see that the file is there and start dumping to it. Seems kind of cheesy, but it works. However, with a website, I'd have to write a full blown asynchronous logger that knew how to queue information to be written, and I don't really want to do that, and I don't know how to achieve this using Enterprise logger. Any ideas on this one would be great.
The other thought was to have a flag in the config file or registry that could be changed while the site is running which would enable that same trace.
I'm looking for ideas or solutions. The main concern is that we need to be able to enable and disable this logging on the fly.
So I wasn't able to find a built-in solution for doing this with EnterpriseLibrary, so this is what I ended up doing and it seems to work; in fact, I extended the idea a bit further by adding a priority override check.
I created a proxy class for writing to the EL LogWriter. What it does is check for the existence of a file (priority_override.txt in this case). If the file is present, it will read the file and search for the text PriorityLevel={n} where n is the override. If it is able to get this override number, it will then override the priority level that was provided in the code. I use this to basically force a high priority on all log statements so that they don't get blocked by the Filter.
My default filter prevents anything below a priority 5 from making it to the listeners; this trick allows me to override that by temporarily increasing the priority of all logs.So since Debug is generally priority 1, it doesn't get logged. If I drop a file in the log directory called priority_override.txt that has the contents PriorityLevel=99, then ALL log statements will make it to the configured listeners and handled accordingly. Everything else is just a normal matter of configuring EL with proper categories and priorities etc. So for instance, if my highest priority is 5 and that triggers an email, then I would just override it to 4 so that everything gets logged but emails do not get sent. Then when we're done troubleshooting in production, for instance, we just delete the priority_override.txt and everything returns to normal.
Additionally, now we don't have to manage the changing of config files separately for our test environments. We can just leave the priority_override.txt in the log folder in each respective environment.