README.md

Servlet logging filter

Java 11 Servlet filter for logging requests and responses

Web page equivalent is here

Usage

Filter implements javax.servlet.Filter from Servlet API 4.0.1 You can register the filter using web.xml descriptor.

<filter>
	<filter-name>LoggingFilter</filter-name>
	<filter-class>javax.servlet.filter.logging.LoggingFilter</filter-class>
</filter>
<filter-mapping>
	<filter-name>LoggingFilter</filter-name>
	<url-pattern>/*</url-pattern>
</filter-mapping>

or javax.servlet.ServletContext

public void onStartup(ServletContext servletContext) throws ServletException {
	Dynamic registration = servletContext.addFilter("LoggingFilter", new LoggingFilter());
	registration.addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), false, "/*");
}

Init params

Name	Default	Description
loggerName	class name	Logger name for output
maxContentSize	1024 bytes	Maximal logged body size in bytes
excludedPaths	empty	Comma sepparated list of URL prefixes e.g.: "/api,/admin"
requestPrefix	REQUEST:	First word on request output line
responsePrefix	RESPONSE:	First word on response output line
requestMarker	RESPONSE	Slf4J marker for request
responseMarker	RESPONSE	Slf4J marker for response
disablePrefix	false	No prefixes are logged if true
disableMarkers	false	No Slf4J markers are logged if true

Customization

There are few methods for rewrite if you want:

Main filter processing

javax.servlet.filter.logging.LoggingFilter.doFilter

Creating description of request. Default is create JSON object.

javax.servlet.filter.logging.LoggingFilter.getRequestDescription

Creating description of response. Default is create JSON object.

javax.servlet.filter.logging.LoggingFilter.getResponseDescription

Output

REQUEST: {"sender": "127.0.0.1", "method": "GET", "path": "http://localhost:8080/test", "params": {"param1": "1000"}, "headers": {"Accept": "application/json", "Content-Type":"text/plain"}, "body": "Test request body"}
RESPONSE: {"status":200,"headers":{"Content-Type":"text/plain"},"body":"Test response body"}