log4net - per user logging - log4net

Please help me with this query in using log4net.
I am using log4net in mhy we application. I am facing issues in configuring log4net to log errors at user level.
That is, If user X logs in, I like to create file name X and all error for user X should be written in X.log. Siilarly if Y user logs in the log file should be in name of Y.log and the most important point to note is, they could log in concurrently.
I tried the luck by creating log files whose name would be framed dynamically as soon as the user logs in. But issue here, if they are not using the application at the same time, the log files are creeated with correct name and writing as expected, but if both users have active sessions, log file is created only for user who FIRST logged in and error of second user has been recorded in log file that is created for FIRST user.
Please help me in this.

There has to be a better solution from this one, but you can change log4net configuration from code and even decide which config file to load - so you can do it in code, which is not as nice as editing an XML file.
so what you need to do, which is highly not recommended, is to create log4net configuration each time you call the logger static class, and do what needed based on the calling user.
again.. it doesn't feel right !
(and it will probably perform poorly).
another BETTER solution is to log everything to database (log4net supports it), with a user column, and then produce the logs from db....

Related

XPages OpenLog - Logging to wrong database

Apologies Paul, this is a duplicate to the post I put on OpenNTF, however the site will not allow me to log in the last 2 days to follow up, plus the wider audience of Stack might find me someone with an identical issue.
To keep it short.
I have 1 openLog database in a folder structure, logs/xpageslog.nsf
During development, I could log to this database, for example, using Paul Withers XPages OpenLog Logger, to log uncaught exceptions with the following settings:
private String logDbName = "logs\\xpageslog.nsf"; // in OpenLogItem.java from OpenLogClass library
logDbName = "logs/xpages.nsf" // in OpenLogFunctions.ls
xsp.openlog.filepath=log/xpageslog.nsf // in xsp.properties
However, if I then change all the above, to simply go to xpageslog.nsf, in the root of the server (this is a 2nd openLog database) errors still get logged to the first database.
I've tried building, cleaning, re-compiling, all to no avail. It seem's to be that somewhere, or somehow, the references to the original database are not being overwritten.
Any ideas?
It is good practice to use restart task http instead of tell http restart. Both commands have different effects.
As confirmed in comments, this solved the problem.
Some use tell http quit followed by load http, the effect is the same as with restart task http. At the other hand, simple tell http restart does not fully initialize http task, it's kind of soft reset and I recommend not using it.

Sentinel configuration with NLog/log4net

I have just started to use logging for my C# application. I am using NLog for logging entries to a *.log file and I view it using a Notepad++.
I want to try Sentinel, although I can view the logs on sentinel, I am not sure with the initial steps of sentinel, do I have to do the following every time I want to start sentinel to read a log?
Add new logger
Provider registration - NLog viewer
Visualizing the log
Cant I just start the sentinel and choose from a set configuration files ? If I am running two C# applications one using Log4Net and another Nlog, do I have to go through these over again instead of just selecting a config file?
Also what is the purpose of saving a session in sentinel ?
Once you have a session saved in a file - file.sntl - you can instruct Sentinel to pull that session in on startup by supplying the filename on the command line. I have nlog.sntl saved and use the following from a command script:
#echo off
start /B c:\apps\sentinel\sentinel nlog.sntl
I'm sure you'd be able to create a program shortcut with the same information - I just can't be bothered

Azure failed request error details

I've got an Azure app up and running, but various requests generate a 500 error. There are no other details that come back from the server to let me know exactly what the problem is. No stack trace, no error message. The only thing I get back from the server are the http headers indicating I've got an error.
I've done a little looking around but can't seem to find a way to retrieve the error details that I'm looking for. I've seen some articles that suggest that I enable logging, but I'm not sure 1) how to do that, 2) where those log files would go and 3) how to access said log files. I've seen posts that say to add a whole bunch of code to my application to enable logging, but all I'm looking for is an error message and a stack trace from a 500 error. Do I really have to add a bunch of code to my app to see that information? If not, how can I get at it?
Thanks!
Chris
The best long-term solution is to enable Azure Diagnostics, which I think is what you're referring to. If you want a quick-and-dirty solution, you can log errors out to a file and then RDP into the role instances to view them. This is very similar to what you would do on a server in your own datacenter.
You can create the logs however you like. I've used log4net and RollingFileAppenders with some success. Setting the logfile path to something like "\logs\mylog.txt" will place the logs in the E: drive of the VM. Note you'll still need code somewhere in your app to capture the error and write it to the log - typically the global error handler in Global.asax is a good place for that.
You'll also have to enable RDP access to your role instances. There are many articles detailing how to do that. Here's one.
This is not a generally recommended approach because the logs may disappears when the role recycles or is recreated. It's also a pain in the butt to log to keep an eye on all those different servers.
One other warning - it's possible that the 500 error is due to some failure in your web.config. If that is the case, all the the application-level error logging in the world isn't going to help you. So be sure that your web.config is valid, and also check the Windows Event Logs while you're RDP'd into the server.
500 internal server error is most generally caused by some problem on the server when it was not able to understand incoming requests or there was some problem in configuration. So, try to run the app locally and see if there is some problem. You can record errors in a database in catches/application_error and also can use tracing. Believe me they are very helpful and worth a few extra lines of code.
For tracing have a look here, http://msdn.microsoft.com/en-us/magazine/ff714589.aspx

Get an entry ID for log4net ADONetAppender

I am using log4net in a web app, and log all page errors to a SQL server. I was wondering if there was any way to retrieve the entry ID generated by it. I'm going off of the documentation found here
http://logging.apache.org/log4net/release/config-examples.html
I want to use this ID as a reference number I can show to a customer so that they may contact customer support to lookup in the system and not have to go through a log file.
Apart from writing your own appender as floyddotnet suggested you could consider:
Use a GUID. You can easily generate it in your application and will serve most of your purposes. Drawback: It may be inconvenient for the customers if they try to tell your support stuff about it on the phone. If you have only email support than this is maybe not an issue.
Consider creating an incident number outside of the logging framework. A quick call to a stored procedure that returns an ID that you save in a nullable field in your log table.
A combination of the above: Use a Guid and after logging you call a stored procedure that creates an incident and returns the ID.
Writing an appender that returns the ID creates a dependency between your application and appenders that you normally do not have: Log4net was designed with a clear separation between logging and writing the log messages somewhere. The appender that you need would affect that separation.
Since the ID is generated by the database and not by log4net, I don't believe this information is available to you.
What I've done in using log4net for such conditions is to include a datetime stamp in the message that goes down to the millisecond and present that to the user as a reference number. You can do then do a simple SQL query to get to the message in the log table.
I'm not sure its posible but you can write your own Appender for log4net end store this information in the log4net-context.
Howto writing an appender for log4net:
http://www.alteridem.net/2008/01/10/writing-an-appender-for-log4net/
Context-Description:
http://logging.apache.org/log4net/release/manual/contexts.html

selecting a log file

We have multiple log files like database log, weblog, quartzlog in our application.
Any log from files under package /app/database will go to database log.
Any log from files under package /app/offline will go to quartzlog log.
What we need now is - want to direct the log staments from one of the java file under /app/database to be outputted to quartzlog instead of database log.
How can we select a particular log file in java file?
You need to define the appropriate appender that logs in the desired file. Read this short introduction to see how you can do it.
Then in the configuration file, you can instruct all messages from a specific package to go in the selected appender:
log4j.logger.my.package = DEBUG, myFileAppender
EDIT:
I believe that in log4j only package resolution is possible - you can't use an appender per file or method. You could try to work around this by adding an extra layer on top of log4j or implementing your own appender.
For example, instead of log.debug use:
my.loggerproxy.log.debug(message);
If you only need to do it from a single method, then the above will be enough. Just instruct the logger proxy package to be logged in a different file.

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