Log4Net - Output not showing up at file - log4net

I have an Log4Net configuration that produces output as expected in a console application.
I have the exact same config, and invokation code (all done at the earliest point possible in the execution flow), but in the context of NUnit tests.
I know the configuration is loaded correctly. Additionally, I have turned the system diagnostics for Log4Net, and the debug prints are the exact same in both cases.
In the console application the text gets written. Otherwise, the file is empty.
The configuration code:
<log4net>
<!--APPENDERS-->
<!--Endpoint File Appender-->
<appender name="EndpointFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:\Temp\Endpoint.log" />
<appendToFile value="true" />
<maximumFileSize value="100KB" />
<maxSizeRollBackups value="10" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%message" />
</layout>
</appender>
<!--LOGGERS-->
<logger name="EndpointLog">
<level value="ALL" />
<appender-ref ref="EndpointFileAppender" />
</logger>
The Invocation code (first thing at application boot):
log4net.Config.XmlConfigurator.Configure();
ILog log = LogManager.GetLogger("EndpointLog");
log.Info("Hello World.");
Any ideas? Thanks

Is it that you need a root section? Try adding this:
<root>
<level value="All" />
<appender-ref ref="EndpointFileAppender" />
</root>

When you are running in an unittest context, you need to copy the log4net config into the bin folder with your unittest dlls. You can do this by setting copy tot output folder on the log4net config.

Related

Log4net RollingFileAppender not writing when application runs as a service

I have an C# application that can run on Windows 10 either as a console app or as a service, depending on a configuration parameter. I am writing log messages using a log4net RollingFileAppender. I'm using log4net version 4.5. When the application runs as a console app, the rolling file gets written as expected. When it is run as a service the file does not get written. What can I do to get my log file?
Here's the configuration file:
<?xml version="1.0" encoding="utf-8"?>
<log4net>
<appender name="TimedFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="c:/misc/HotspotControlService.log" />
<appendToFile value="true" />
<rollingStyle value="Date" />
<datePattern value="yyyyMMdd.lo\g" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date - %message%newline" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="TimedFileAppender" />
</root>
</log4net>
As usual, my own idiocy is the problem. I specified the configuration file in my program by the bare file name, with no folder given. The file exists in the same folder as my executable file. But when running as a service, the working folder is not the folder in which the executable folder lives. I used an absolute path for the configuration file name, and it worked.

What's wrong with my log4net config file

I have a config file with two appenders, one file appender and one database appender. I want to log everything to the file appender, and only log exceptions to the database appender. When setting up both appenders in the section it logs fine but all log events are sent to both appenders, which is not what i want.
I changed the configuration but with this current configuration, exceptions get logged to the database, and nothing is getting written to the file appender. Can anyone tell me why I am not getting anything written to the file appender?
<log4net debug="true">
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:\Log4net\Workflow\TestLog.txt" />
<threshold value="All" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10KB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%-5p {%logger} %d %5rms %-22.22c{1} %-18.18M - %m%n" />
</layout>
</appender>
<appender name="AdoNetAppender" type="log4net.Appender.AdoNetAppender">
<!-- Removed to keep this snippet simple-->
</appender>
<root>
<level value="Error" />
<appender-ref ref="AdoNetAppender" />
</root>
<logger name="AllLogs">
<level value="ALL" />
<appender-ref ref="RollingLogFileAppender" />
</logger>
</log4net>
What you have here is the following:
all logs events with the level Error or more will go to the AdoNetAppender
all logs events originating from a logger whose name is based on AllLogs will go to the RollingLogFileAppender
From what I understand you want all logs to default to the file, and only error ones to go also to the database. Then simply add both appenders to your root logger so that both get all events, and add filters to only let filters you're interested in pass through: a level range filter on your database appender would work
<log4net debug="true">
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<!-- rest of config snipped to save space -->
</appender>
<appender name="AdoNetAppender" type="log4net.Appender.AdoNetAppender">
<filter type="log4net.Filter.LevelRangeFilter">
<levelMin value="ERROR" />
<levelMax value="FATAL" />
</filter>
<!-- rest of config snipped to save space -->
</appender>
<root>
<appender-ref ref="AdoNetAppender" />
<appender-ref ref="RollingLogFileAppender" />
</root>
</log4net>
Of course if you don't want any duplicate just filter errors and above in the rolling file appender

log4net doesn't watch my app.config

I configured my log4net to watch on changes made to the app.config file.
[assembly: log4net.Config.XmlConfigurator(Watch = true)]
When I run my app and change things in the config file, these changes only take effect when I restart my app. Why could this be?
Is there also a way to tell log4net to watch on changes in the app.config? Like:
<appender name="FileAppender" type="log4net.Appender.FileAppender" >
<watch value="true" />
</appender>
------------- EDIT -------------
I tried now to use a separate config-file: log4net.config.
It looks like this:
<log4net>
<appender name="FileAppender" type="log4net.Appender.FileAppender">
<file value="c:\log.txt" />
<appendToFile value="true" />
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%d [%t] %-5p %c (line %L) -- %m%n" />
</layout>
</appender>
<root>
<appender-ref ref="FileAppender" />
</root>
</log4net>
In my assemblyInfo.cs I wrote the following:
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "log4net.config", Watch = true)]
The class that logs to the file looks like this:
ILog myLogger = LogManager.GetLogger(typeof(Form1));
myLogger.Debug("test");
This works like the old version. logfile entries are made, but when I change my log4net.config during runtime, these changes are not applied.... "Watch=true" should enable that feature, right?
HA!, I was just encountering the same problem, running unit tests that require logging.
Adding this line fixed it:
log4net.Config.XmlConfigurator.Configure();
My App.config:
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="log.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="100KB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="RollingFileAppender" />
</root>
</log4net>
I also do have this:
[assembly: log4net.Config.XmlConfigurator(Watch = true)]
According to log4net documentation, the Watch feature does not work for application configuration files (app.config, web.config):
Because the System.Configuration API does not support reloading of the config file
the configuration settings cannot be watched using the
log4net.Config.XmlConfigurator.ConfigureAndWatch methods.
So if you need the log4net configuration to be re-configurable, you will need to place it in a separate XML file and your application needs to have sufficient permissions to read the file:
The file to read the configuration from can be specified using any of the log4net.Config.XmlConfigurator methods that accept a System.IO.FileInfo object. Because the file system can be monitored for file change notifications the ConfigureAndWatch methods can be used to monitor the configuration file for modifications and automatically reconfigure log4net.
Even though I'm terribly late to the party - here's, what helped me: a simple call to log4net.LogManager.GetLogger("DUMMY"); at the very beginning of my program. I put it in the very first line of program.cs's Main() method. No need to assign the logger to any object, merely a polite request to log4net to read the assembly's attributes as stated here.
Using attributes can be a clearer method for defining where the application's configuration will be loaded from. However it is worth noting that attributes are purely passive. They are information only. Therefore if you use configuration attributes you must invoke log4net to allow it to read the attributes. A simple call to LogManager.GetLogger will cause the attributes on the calling assembly to be read and processed. Therefore it is imperative to make a logging call as early as possible during the application start-up, and certainly before any external assemblies have been loaded and invoked.

Log4Net section in Web.Config generates Error

So I am trying to set up Log4Net in my Web .NET 4.0 application. I have added the correct .dll to my project and have appended the following to my Web.Config file as starters:
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
<root>
<level value="DEBUG" />
<appender-ref ref="RollingLogFileAppender" />
</root>
</configSections>
<log4net debug="true">
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:\\TestProj\\TestLog.txt" />
<appendToFile value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%-5p %d %5rms %-22.22c{1} %-18.18M - %m%n" />
</layout>
</appender>
However, if I append the "log4net" section to Web.Config, I will receive the error message
Unable to start debugging on the web server. See help for common
configuration problems.....
Make sure the server is running correctly. Verify there are no syntax
errors in the web.config........
NOTE
I can remove all the internals of this section and leave only the declaration:
<log4net></log4net>
and I will still get the same error.
Can someone give me some pointers on how to track down this error?
For developers who are not sure exactly how to get started following might be a help
ConfigSections in app.config
Remember to tell your application that a library is introducing a custom configuration section are you are intended to utilize, I am not perfectly sure if it is mandatory or not but I always use it as first section within root <configuration> tag.
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
log4net config in app.config
There are quite a variety of different appenders available in log4net but I usually use RollingFileAppender so I am using the same one in this sample, you can find rest of those here.
<log4net>
<!-- file appender -->
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:/logs/my_log_file.log"/>
<appendToFile value="true"/>
<rollingStyle value="Date"/>
<maxSizeRollBackups value="30"/>
<datePattern value=".yyyy-MM-dd"/>
<staticLogFileName value="true"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger - %message%newline"/>
</layout>
</appender>
<root>
<level value="DEBUG"/>
<appender-ref ref="RollingFileAppender"/>
</root>
</log4net>
Update AssemblyInfo.cs file
I always miss this step whenever I have to create a new project. So remember you have to tell your application to watch for XMLConfigurator to perform configuration of log4net, so following line goes at the end of AssemblyInfo.cs file:
[assembly: log4net.Config.XmlConfigurator(Watch = true)]
Get Started
Remember to include the reference of log4net.dll then use following line of code to initialize logger within a class
private static ILog log = LogManager.GetLogger(typeof(MyClass));
And at the end lets use it like following
log.Info("Hello log4net");
Happy Logging :)
Take a look at a sample configurations at log4net documentation homepage.
Chances are you've misplaced required tags.

Turn off Debug Logging during Release in Log4net

When I compiled my application in release mode, I found that the Log4Net still logs debug information; any idea how to fix this?
This is my App.Config file:
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,Log4net"/>
</configSections>
<log4net>
<root>
<level value="DEBUG" />
<appender-ref ref="LogFileAppender" />
</root>
<appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender" >
<param name="File" value="C:\Documents and Settings\test\Application Data\Log.txt" />
<param name="AppendToFile" value="true" />
<rollingStyle value="Size" />
<maxSizeRollBackups value="10" />
<maximumFileSize value="10MB" />
<staticLogFileName value="true" />
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%-5p%d{yyyy-MM-dd hh:mm:ss} - %m%n" />
</layout>
</appender>
</log4net>
Did I miss anything?
There's nothing in your App.Config file to tell log4net to do things differently in release or debug mode. If you want logging to be different between the two builds, you have to change your configuration file between the two builds.
Your best bet is probably to create one App.Config for Release, one for Debug, and then follow the advice in the StackOverflow question:
Deploy an app.config based on build configuration
NOTE: The difference between your release and debug App.Config will be the following line in the debug version
<level value="DEBUG" />
versus the following line in the release version (or of course you could choose ERROR or FATAL if you want):
<level value="INFO" />
Maybe try something like this instead? Set to whatever minimum level you want to receive.
<level value="WARN" />
If your App.Config looks like this:
<root>
<level value="Info" />
<appender-ref ref="ConsoleAppender" />
<appender-ref ref="RollingFileAppender" />
</root>
You can modify the log level by code (put the code in Program.cs):
#if DEBUG
log4net.Repository.ILoggerRepository RootRep;
RootRep = LogManager.GetRepository(Assembly.GetCallingAssembly());
XmlElement section = ConfigurationManager.GetSection("log4net") as XmlElement;
XPathNavigator navigator = section.CreateNavigator();
XPathNodeIterator nodes = navigator.Select("root/level");
foreach (XPathNavigator appender in nodes)
{
appender.MoveToAttribute("value", string.Empty);
appender.SetValue("Debug");
}
IXmlRepositoryConfigurator xmlCon = RootRep as IXmlRepositoryConfigurator;
xmlCon.Configure(section);
#endif

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