This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Framework 6.0.25!

Logging

DEBUG-level logging in Spring MVC is designed to be compact, minimal, and human-friendly. It focuses on high-value bits of information that are useful over and over again versus others that are useful only when debugging a specific issue.

TRACE-level logging generally follows the same principles as DEBUG (and, for example, also should not be a fire hose) but can be used for debugging any issue. In addition, some log messages may show a different level of detail at TRACE versus DEBUG.

Good logging comes from the experience of using the logs. If you spot anything that does not meet the stated goals, please let us know.

Sensitive Data

DEBUG and TRACE logging may log sensitive information. This is why request parameters and headers are masked by default and their logging in full must be enabled explicitly through the enableLoggingRequestDetails property on DispatcherServlet.

The following example shows how to do so by using Java configuration:

  • Java

  • Kotlin

public class MyInitializer
		extends AbstractAnnotationConfigDispatcherServletInitializer {

	@Override
	protected Class<?>[] getRootConfigClasses() {
		return ... ;
	}

	@Override
	protected Class<?>[] getServletConfigClasses() {
		return ... ;
	}

	@Override
	protected String[] getServletMappings() {
		return ... ;
	}

	@Override
	protected void customizeRegistration(ServletRegistration.Dynamic registration) {
		registration.setInitParameter("enableLoggingRequestDetails", "true");
	}

}
class MyInitializer : AbstractAnnotationConfigDispatcherServletInitializer() {

	override fun getRootConfigClasses(): Array<Class<*>>? {
		return ...
	}

	override fun getServletConfigClasses(): Array<Class<*>>? {
		return ...
	}

	override fun getServletMappings(): Array<String> {
		return ...
	}

	override fun customizeRegistration(registration: ServletRegistration.Dynamic) {
		registration.setInitParameter("enableLoggingRequestDetails", "true")
	}
}