We ship a framework assembly for logging which internally uses nlog. We also ship an embedded nlog configuration as a resource in our assembly and read this on startup (a static constructor within our wrapper which wraps over the nlog wrapper using the XmlLoggingConfiguration class).
We would now like developers to be able to specify/override additional configuration via an external file for their own loggers (using the same nlog configuration file format).
Can we:
Refer include files in our embedded nlog configuration file? How is the path of the include file resolved? If we do this, does the content of the include file override the content of the embedded nlog configuration we read on startup?
Can developers use the nlog configuration section? Does the content of this section override the default configuration we have specified pro grammatically?
Any other options?
How is the path of the include file resolved?
You can use in the included file name:
layout renderers such as ${baseDir},
nlog variables.
If the resulting filename is not absolute, it is combined with the directory, where the original NLog configuration was located, but this may be null in your case, so you are limited to first 2 options.
does the content of the include file override the content of the embedded nlog configuration?
No, this content is added to the content of the embedded configuration.
Does the content of nlog configuration section override the default configuration we have specified programmatically?
When you set the configuration programatically, you override any configuration that was set before and also disable the automatic configuration discovery, including one from application configuration file or NLog.config.
But you can check whether the configuration is not null first time before you set the embedded value. This will trigger the automatic discovery, and in case if any logging configuration is found, the returned value would be non-null.
Related
I am running a executable jar file, which logs using log4j.xml(version 1.2).
Whenever i change the log level in the xml file, i have to restart the java application for the new log level to reflect.
Can i add some configuration in the log4j.xml so that new log level will be taken into account without application restart?
Thanks,
-Venkat
Log4j 1.x has reached end of life on August 5, 2015. So I would like to recommend you to use log4j 2.x which supports this with the monitorInterval configuration.
However according to the log4j 1.x docs here it does support log level changes runtime.
How can I change log behavior at runtime?
Log behavior can be set using configuration files which are parsed at
runtime. Using configuration files the programmer can define loggers
and set their levels.
The PropertyConfigurator defines a particular format of a
configuration file. See also the examples/Sort.java example and
associated configuration files.
Configuration files can be specified in XML. See log4j.dtd and
org.log4j.xml.DOMConfigurator for more details.
See the various Layout and Appender components for specific
configuration options.
In addition to configuration files, the user may disable all messages
belonging to a set of levels. See next item.
I'm using Log4j for logging my system events.
Initially I used the Log4j properties file and then shifted to log4j.xml file.
My application has another property file - system.properties - that takes the configuration parameters.
I want the log output file to be specified in the application properties file - system.properties and refer the properties file in the log4j.xml file and also update the configuration.
Is it possible with this log4j.xml configuration?
You can do it by using ant scripts. Load the system.properties file in ant and replace the value inside the log4j.xml file.
Refer to this link on how to update XML file.
How to update an XML document with Ant
I am trying to use log4j logging framework in a java desktop application.
When I run the code I am getting a message
log4j: log4j:WARN No appenders could be found for logger
I googled for the above error and found that it occurs when the log4j.properties file is not found by the app.
I am creating the desktop app using Eclipse. Currently log4j.properties is within the same folder that contains the source (in 'src' folder). Where should I put this file to make it work properly?
log4j will use a Default Initialization Procedure to find your configuration file. The documentation notes:
The preferred way to specify the default initialization file is through the log4j.configuration system property
If this property is not set - log4j will look at the classpath. In your case you have to place the file in the src directory (assumed that the content will be put in the classes path while you build the system). If you use maven place the file to the src/main/resources directory.
As you placed your file to the src directory check, that the file get transferred to the top level directory of your compiled classes.
Keep the properties file in the classes folder i.e. the folder that contains the classes (specially the main class).
Another reason for getting this error may be the wrong appenders or an appender without setting.
I have two different projects 'A' and 'B'.A needs reference of B.I used spring.net setter property injection.I configured it in config file.
I have one more new console application where i added only 'A's reference and im getting the 'A's instance through XmlApplicationConext(path).but after running it im getting object creation exception.
Do i need to add 'B's refrence also in console application.if yes then what is the use of using spring .net config file.
Does Spring.Net internally automatically will load the dlls required.
Spring will automatically load the required dll's. As far as I know, it will look for the dll's to load in the same order as any other .NET application.
If you configure the console application to use classes from project B, then B.dll (the output dll from project B) has to be available to the console application at runtime only. You do not have to add a reference to project B to achieve this; you could also copy the B.dll file to the output directory.
I'm not sure what you mean by "the Spring.net config file", but be aware that config files are not automatically loaded, you have to specify them explicitly. You can import another configuration file in you configuration file, see the docs for a how-to:
<objects xmlns="http://www.springframework.net">
<import resource="file:///services.xml"/>
<import resource="assembly://ProjectB/MyDataAccess/data-access.xml"/>
<object id="object1" type="..."/>
<object id="object2" type="..."/>
</objects>
i'm starting with Log4J and i want to have a default log4j.properties in our Java Web Start distributed application, which only logs errors and important events.
But if something was wrong in one client i want to have a more detailed log, the way to do this is to define an alternate log4j configuration file in this client. This can be done by specifiying the alternate config file with the log4j.configuration system property.
but... How can i define an system property for this particular client in a java web start launched application? (i know that i can define theese propeties in the .jnlp file, but this affects all clients).
Our users work in windows environment but they often have a restricted permissions computer and they can't acces My Pc->Properties-->Advanced Options-->Enviroment Variables (i'm in a spanish configured computer i don't know the exact names in english).
Can you access to a defined directory on the client disk ?
If you can, you can define a convention : if no configuration file is found in the directory, the default config is used. Else, the specific configuration file is loaded.
You can do that with the PropertyConfigurator class of Log4J :
File log4jConfigFile == new File(conventionLocation);
if(log4jConfigFile.isFile() && log4jConfigFile.exists()) {
PropertyConfigurator.configure(conventionLocation);
} else {
PropertyConfigurator.configure(defaultEmbeddedJarLocation);
}
First off if you are using applets you should use an appender that can write to a remote location so you can actually see the errors without being physically on the local machine that the applet is running. Appender Types. Next, you need to create an appender with a threshold of whatever level you are logging the normal "access" type messages. Set the layout to whatever you desire. Then create another appender with a level of at least the level you log "errors" at as well as its own format that suits your needs as being "more detailed". That way when your code calls an error message it will use that different layout. Log4j is fairly complex but not impossible to understand. Look at the documentation at The log4j site and get your feet wet on some simple logging. After that you should be able to modify the code to get what you desire.