The logging facility provides a seamless way to add logging capabilities to your application. There are two levels of integration.
- Allow your classes to receive an
ILogger
instance for logging support - Allow you to ask for an
ILoggerFactory
instance to provide logging support to classes that are not managed by Windsor.
ℹ️ Logger abstraction: Castle Project does not contain its own logging framework. There are already excellent frameworks out there. Instead ILogger
and ILoggerFactory
are abstractions Windsor uses to decouple itself from the framework you decide to use.
Castle Core provides many logger abstraction implementations, however you can also create your own.
The recommended way of configuring the facility is using code. When specifying custom ILoggerFactory
or IExtendedLoggerFactory
you use the following generic overload:
container.AddFacility<LoggingFacility>(f => f.LogUsing<CustomLoggerFactory>());
For example, using the log4net logger factory with configuration stored in a log4net.xml
file, the code would look like this:
container.AddFacility<LoggingFacility>(f => f.LogUsing<Log4netFactory>().WithConfig("log4net.xml"));
There are a few helper methods for built-in logging factories:
// Null Logger
container.AddFacility<LoggingFacility>(f => f.LogUsingNullLogger());
// Console Logger
container.AddFacility<LoggingFacility>(f => f.LogUsingConsoleLogger());
// Diagnostics Logger
container.AddFacility<LoggingFacility>(f => f.LogUsingDiagnosticsLogger());
// Trace Logger
container.AddFacility<LoggingFacility>(f => f.LogUsingTraceLogger());
It is also possible to configure the facility via XML. For example the same configuration for log4net as above:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<facility
type="Castle.Facilities.Logging.LoggingFacility, Castle.Facilities.Logging"
customLoggerFactory="Castle.Services.Logging.Log4netIntegration.Log4netFactory, Castle.Services.Logging.Log4netIntegration"
configFile="log4net.xml" />
</configuration>
The full list of configuraation attributes is shown in the following example:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
<facility
type="Castle.Facilities.Logging.LoggingFacility, Castle.Facilities.Logging"
customLoggerFactory="<type of factory>"
configFile="<path to configuration file (optional attribute)>"
loggerLevel="<the loggerLevel (optional attribute)>"
configuredExternally="<boolean value (optional attribute)>" "/>
</configuration>
We recommend that you make logging optional on your components/services. This way you maximize the reusability. For example:
using Castle.Core.Logging;
public class CustomerService
{
public CustomerService()
{
}
public ILogger Logger { get; set; } = NullLogger.Instance;
// ...
}
With the approach above, the logger field will never be null. Also, if the logging facility was registered on the container, it will be able to supply a logger instance using the Logger
property.
Castle.Facilities.Logging.dll
(bundled with Windsor)Castle.Core.dll
(contains theILogger
andILoggerFactory
interfaces; included as a dependency in the Windsor NuGet package)