I have a configuration file for my project that includes the configuration for the log4net logger.
It is as it follows:
<log4net>
<appender name="LogFileAppender" type="log4net.Appender.FileAppender">
<file value="MyLogFile.txt" />
<appendToFile value="true" />
<layout type="log4net.Layout.PatternLayout">
<header value ="Start file processing..."/>
<conversionPattern value="%newline%date - %message%exception" />
<footer type="log4net.Util.PatternString" value="File processing finished.%newline%newline" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="LogFileAppender" />
</root>
</log4net>
I am wondering if it is possible dynamicaly to change the value of my :
<file value="MyLogFile.txt" />
Simplest way to dynamically change log4net configuration, is setting xml configurator to watch changes of config file:
[assembly: XmlConfigurator(Watch = true)]
When you will do some changes to application config file (one which lives near exe) log4net will automatically reconfigure itself and further output will go to other file.
If you for some reason want to do this programatically then you need to get instance of file appender from logger repository (aka Hierarchy):
var fileAppender = LogManager.GetLoggerRepository()
.GetAppenders()
.OfType<FileAppender>()
.FirstOrDefault(fa => fa.Name == "LogFileAppender");
And change it's settings:
if (fileAppender != null)
{
fileAppender.File = Path.Combine(Environment.CurrentDirectory, "foo.txt");
fileAppender.ActivateOptions();
}
Keep in mind, that simple setting File property will not open new file - it just sets file name which should be opened during appender activation. So, you need to activate it manually just after changing file path.
Yup, you can access the appender at runtime and change the properties of it. Just make sure you call ActivateOptions after changing anything.
Here's an example that changes the connection string for an ADO appender. You should be able to adapt that easily enough for what you are trying to do:
http://blog.gfader.com/2010/05/log4net-how-to-change-settings-of.html
You can read the log4net file, parse it with a xml parser in your application and change the file value attribute. Then save the log4net file. If you have watch=true, the new configuration will be picked up as the new configuration.
You can do some thing like this also
<file type="log4net.Util.PatternString" value="%property{LogFileName}.log" />
ILog logger = LogManager.GetLogger("SampleAppender");
log4net.GlobalContext.Properties["LogFileName"] = "MyLog";
XmlConfigurator.Configure();
Related
I have a third party using a configuration file that looks like this:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net" />
<!--Others sections-->
</configSections>
<log4net>
<appender name="RollingFileAppender" type="log4net.Appender.RollingFileAppender">
<file value=".\logs\logclient.txt" />
<appendToFile value="false" />
<rollingStyle value="Date" />
<maximumFileSize value="1000KB" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%date [%thread] %-5level %logger [%ndc] - %message%newline" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="RollingFileAppender" />
</root>
</log4net>
</configuration>
The code in the third party looks like :
LogManager.GetRepository(Assembly.GetCallingAssembly()), configFile);
LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
I would like the third party dll to use my own appender defined in my own configuration file. How can I managed this ?
NB :
the third party need to use its own configuration file because others
sections are mandatory and I can not add them in my file
I can modify the third party configuration file, I can not modify mine
There are two existing questions that propose a solution to dynamically edit log4net configuration:
Dynamically reconfigure Log4Net
How can I change the file location programmatically? (see JackAce answer).
As far as I understand, you must use the third party configuration file and you can modify it.
The configSource property/attribute should work to redirect the log4net configuration section of your third party configuration file.
In the third party configuration file :
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net" />
</configSections>
<log4net configSource="pathtoyourlog4net.config" />
log4net library is a tool to help the programmer output log statements
to a variety of output targets.
You can also configure log4net in code instead of using a config file,this SO post clearly explains the question.
Change appender dynamically:
public static void ChangeFilePath(string appenderName, string newFilename)
{
log4net.Repository.ILoggerRepository repository = log4net.LogManager.GetRepository();
foreach (log4net.Appender.IAppender appender in repository.GetAppenders())
{
if (appender.Name.CompareTo(appenderName) == 0 && appender is log4net.Appender.FileAppender)
{
log4net.Appender.FileAppender fileAppender = (log4net.Appender.FileAppender)appender;
fileAppender.File = System.IO.Path.Combine(fileAppender.File, newFilename);
fileAppender.ActivateOptions();
}
}
}
Reference post
If your .NET app is referencing the thirdparty.dll, at runtime the app will ignore the thirdparty.dll.config completely. Also, the thirdparty.dll will not pickup the settings in the thirdparty.dll.config as it is expecting these to be loaded by the exe.
What you have to do is to merge (or replicate) the content of the thirdparty.dll.config into your own app.config. Both your app and the thirdparty.dll will be able to pickup the settings in your app.exe.config and you only need to maintain one .config file.
Furthermore, you can then add additional appenders to the log4net section and it will be picked-up by both your app and the thirdparty.dll.
I followed logging instructions given here:
I created a Assembly.cs that has this the following:
[assembly: log4net.Config.XmlConfigurator(Watch = true)]
This is my web.config file:
<configuration>
<configSections>
<section name="log4net"
type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
</configSections>
<log4net>
<appender name="FileAppender"
type="log4net.Appender.FileAppender">
<file value="C:\Users\SOIS\Documents\Visual Studio 2010\WebSites\DummyPharmacy\logfile.txt" />
<appendToFile 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="FileAppender" />
</root>
</log4net>
</configuration>
My connection class where I use logger has this:
using log4net;
public class Connection
{
private static readonly ILog log = LogManager.GetLogger(typeof(Connection));
The debug shows execution of the logging. No file created in my folder though. What went wrong?
My output file has this:
log4net:ERROR Failed to find configuration section 'log4net'
in the application's .config file.Check your .config file
for the <log4net> and <configSections> elements. The configuration
section should look like: <section name="log4net"
type="log4net.Config.Log4NetConfigurationSectionHandler,log4net" />
I have made a separate log4net.config file. Because editing the existing one does not allow me to define a element.
This is because you didn't tell log4net to read config from your log4net.config file in your assembly attribute:
see the Configuration Attributes in official document:
// Configure log4net using the .config file
[assembly: log4net.Config.XmlConfigurator(Watch=true)]
// This will cause log4net to look for a configuration file
// called TestApp.exe.config in the application base
// directory (i.e. the directory containing TestApp.exe)
// The config file will be watched for changes.
Change it to following should work:
[assembly: log4net.Config.XmlConfigurator(ConfigFile="log4net.config",Watch=true)]
Or if you prefer a single .config file, then keep the attribute and move the configruations from log4net.config to Web.config.
I would like to set the full path and the file name for the log file (I use log4net) and I would like to use the c:\ProgramData\Logs folder. I get the path of the ProgramData folder using the environment variable #PROGRAMDATA#.
I would like to set the path for the log file in the next way: I use a property in the App.config, and I set the value for this property in the class where I do the loggings.
My App.config file:
<configuration>
...
<log4net>
<appender name="Console" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<!-- Pattern to output the caller's file name and line number -->
<conversionPattern value="%5level [%thread] (%file:%line) - %message%newline" />
</layout>
</appender>
<appender name="AppRollingFile" type="log4net.Appender.RollingFileAppender">
<file type="log4net.Util.PatternString" value="%property{ProgramDataPath}\Logs\Application.log" />
<lockingModel type="log4net.Appender.FileAppender+MinimalLock" />
<appendToFile value="true" />
<maximumFileSize value="1000KB" />
<maxSizeRollBackups value="5" />
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="[%-5level][%d{yy-MM-dd HH:mm:ss,fff}] %m%n" />
</layout>
</appender>
<root>
<level value="DEBUG" />
<appender-ref ref="Console" />
<appender-ref ref="AppRollingFile" />
</root>
</log4net>
</configuration>
And the code where I set the property:
static void Main(string[] args)
{
log4net.GlobalContext.Properties["ProgramDataPath"] = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
log4net.Config.XmlConfigurator.Configure();
My problem is that an empty log file is created before the value of the property is set (then the property it is null). The initialization of the log4net it is done before entering in the main function of the class where I set the property, so it will always be created an empty file in the application's folder: bin\Debug(null)\Logs\Application.log. After I set the property, everything works fine, because another Apllication.log file will be created in c:\ProgramData\Logs folder.
My question is that how can I set the value of the property before the empty log file is created/before entering in the main function of the class where I set the property, or what other solution is there?
Using the environment variable in the App.config as it is shown below did not work.
<file type="log4net.Util.PatternString" value="${PROGRAMDATA}\Logs\Application.log"/>
Try
<file type="log4net.Util.PatternString" value="${ProgramData}\Logs\Application.log"/>
The environment variables are case sensitive, which is why ${PROGRAMDATA} does not work.
Removing the assembly attribute should fix the problem:
[assembly: log4net.Config.XmlConfigurator(Watch=true)]
If you want log4net to watch app.config for configuration changes, use this code (I prefer to put log4net configuration in a separate log4net.config file for easier reuse):
log4net.GlobalContext.Properties["ProgramDataPath"] = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
FileInfo configFile = new FileInfo(Process.GetCurrentProcess().MainModule.FileName + ".config");
log4net.Config.XmlConfigurator.ConfigureAndWatch(configFile);
I am using Log4Net as the logging mechanism for an application of ours. Our configuration is contained in a config file and in our code we programatically invoke which of our several loggers (mostly using FileAppenders) we want to invoke. Recently I realized that one of our log files was not being populated, and I tracked it down to a string mismatch, between the name in our configuration file and the name we were programatically invoking in our code. Because the LogManager could not find the specified logger the root was returned, which for our config is not setup to meaningfully log anywhere.
My question is, is there a way to setup log4net to allow for using specific loggers, but that will fall back to a general logger if the specified logger is not found?
For example using a configuration file like this
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,log4net" />
</configSections>
<log4net>
<root>
<level value="ALL" />
<appender-ref ref="ConsoleAppender" />
</root>
<logger name="TestFileLogger">
<level value="ALL" />
<appender-ref ref="TestFileAppender" />
</logger>
<appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender">
<layout type="log4net.Layout.PatternLayout">
<param name="ConversionPattern" value="%d [%t] %-5p [%x] - %m%n" />
</layout>
</appender>
<appender name="TestFileAppender" type="log4net.Appender.RollingFileAppender">
<param name="File" value="TestLog" />
<param name="DatePattern" value=".yyyyMMdd".log"" />
<param name="AppendToFile" value="true" />
</appender>
</log4net>
</configuration>
And invoking the loggers in C# like this
var fileLogger = LogManager.GetLogger("TestFileLogger");
fileLogger.Info("This logs appropriately.");
var bogusLogger = LogManager.GetLogger("Bogus");
bogusLogger.Info("This should go to a general log. Bogus is not a recognized appender");
Is there a good way to log the messages from bogusLogger to some kind of general log file? My initial thought was to create a general file appender that is part of the root node, but this is very noisy as ALL log messages will be routed to this file. Is there a way to ONLY route messages that are not captured in another log file?
You could use LogManager.Exists("Bogus") to determine if the bogus-logger or your default implementation should be used.
You could create an extensionmethod on LogManager that could handle it for you.
I'm not sure if this is the right forum to post this question. But I'm just hoping someone here might have used log4net in the past, so hoping to get some help.
I'm using log4net to log my exceptions. The configuration settings look like this:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<configSections>
<section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net"/>
</configSections>
<log4net debug="false">
<appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
<file value="C:\Logs\sample.log" />
<appendToFile value="true"/>
<rollingStyle value="Size"/>
<maxSizeRollBackups value="10"/>
<maximumFileSize value="10MB"/>
<staticLogFileName value="true"/>
<layout type="log4net.Layout.PatternLayout">
<conversionPattern value="%-5level %date %logger.%method[line %line] - %message%newline"/>
</layout>
</appender>
<root>
<level value="INFO"/>
<appender-ref ref="RollingLogFileAppender"/>
</root>
</log4net>
</configuration>
I started out by adding this configuration to web.config, but I got an error (VS studio could not find a schema for log4net-"Could not find schema information for the element log4net"). So I followed this link (Log4Net "Could not find schema information" messages) and configured my settings in a separate xml file and added the following line of code in my AssemblyInfo.cs:
[assembly: log4net.Config.XmlConfigurator(ConfigFile = "xmlfile.xml", Watch = true)]
And in the actual code, I placed this line:
public void CreateUser(String username, String password)
{
try
{
log.Info("Inside createuser");
//code for creating user
}
catch(exception e)
{
log.Info("something happened in create user", e);
}
}
The problem is that the log file is not being created. I can't see anything inside C:\Logs. Can anybody tell me what I'm doing wrong here?
Any suggestions/inputs will be very helpful.
Thank you all in advance.
I could not get the setting in Asembly.cs to work without adding this to Application_Start in my Global.asax:
log4net.Config.XmlConfigurator.Configure();
Your log file is not being created probably because the ASPNET user does not have permission to write to the C:\Logs\ directory. Make sure you give full rights to ASPNET to wherever your applicaton wants to create the log file.
So you are loading the configuration file but are you then setting the log variable like so
private static readonly ILog log = LogManager.GetLogger(typeof(Program));
Unless you specify a full path for the separate config file log4net expects the file to be in the path returned by:
System.AppDomain.CurrentDomain.BaseDirectory
If you have a simple console application, this usually means the directory containing the assembly but this is not necessarily true in other cases. There are many ways to solve this problem (c.f. my answer here as well).
To start it might be easier to put the log4net configuration back to the app/web.config and ignore the schema warning. If logging works then you can be sure you have no permission issues and can move to the next step to have the configuration in an external file.
What kind of application are you writing? Maybe I could be a bit more specific with my answer...