Logging in Selenium (Web Driver) using Log4j

log4j, a logging library for JavaThere are three ways to configure log4j: with a properties file, with an XML file and through Java code

Five standard log4j levels

DEBUG Level

This log4j level helps developer to debug application. Level of message logged will be focused on providing support to a application developer.

INFO Level

This log4j level gives the progress and chosen state information. This level will be generally useful for end user. This level is one level higher than DEBUG.

WARN Level

This log4j level gives a warning about an unexpected event to the user. The messages coming out of this level may not halt the progress of the system.

ERROR Level

This log4j level gives information about a serious error which needs to be addressed and may result in unstable state. This level is one level higher than WARN.

FATAL Level

This log4j level is straightforward and you don’t get it quite often. Once you get this level and it indicates application death.

Log4j Logger Output

When a logger is created, generally you assign a level. The logger outputs all those messages equal to that level and also all greater levels than it. So the order for the standard log4j levels are:

Log4J Levels	TRACE Level	DEBUG Level	INFO Level	WARN Level	ERROR Level	FATAL Level
TRACE Level	Y	Y	Y	Y	Y	Y
DEBUG Level	N	Y	Y	Y	Y	Y
INFO Level	N	N	Y	Y	Y	Y
WARN Level	N	N	N	Y	Y	Y
ERROR Level	N	N	N	N	Y	Y
FATAL Level	N	N	N	N	N	Y
ALL Level	Y	Y	Y	Y	Y	Y
OFF Level	N	N	N	N	N	N

Within either you can define three main components: Loggers, Appenders and Layouts. 

Loggers are logical log file names.Each logger is independently configurable as to what level of logging (FATAL, ERROR, etc.) it currently logs.

The actual outputs are done by Appenders.

Appenders use Layouts to format log entries. A popular way to format one-line-at-a-time log files is PatternLayout, which uses a pattern string, much like the C / C++ function printf.

WHY LOGGING....?
Logging helps us in evaluating the cause of code failure.

We need to import log4j jar file into our project for writing logging code.

Steps to enable logging in your project:  

1.Create a property file having extension properties.Name can be log4j.properties.

  

Insert the below code in the log4j.properties file: 

#Application Logs  

  #Logger:Responsible for capturing logging Information

  

  log4j.rootLogger=INFO,dest1

  #Appender:Responsible for publishing captured logging information to various preferred destinations.  

  

  log4j.appender.dest1=org.apache.log4j.RollingFileAppender  

  log4j.appender.dest1.maxFileSize=5000KB  

  log4j.appender.dest1.maxBackupIndex=3  

  #Layout:Responsible for formatting logging information  

  log4j.appender.dest1.layout=org.apache.log4j.PatternLayout  

  log4j.appender.dest1.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss}-%t-%x-%-5p-%-10c:%m%n  

  

log4j.appender.dest1.File=C:\\logs\\Application.log

  #Do not want to append the old file, want to create a new log file every time then  

  log4j.appender.dest1.Append=false

Note: 

• The level of the root logger is defined as INFO and attaches appender named dest1 to it.
• org.apache.log4j.RollingFileAppender is used to roll files when they reach a defined size.
• Set the maximum size that the output file is allowed to reach before being rolled over to backup files.
• If you want to generate your logging information in a particular format based on a patten then you can use org.apache.log4j.PatternLayout to format your logging information.
• d	Used to output the date of the logging event. For example, %d{HH:mm:ss,SSS} or %d{dd MMM yyyy HH:mm:ss,SSS}.

t	Used to output the name of the thread that generated the logging event.

p	Used to output the priority of the logging event.

m	Used to output the application supplied message associated with the logging event.

n	Outputs the platform dependent line separator character or characters.

%	The literal percent sign. %% will print a % sign.

Example

import org.apache.log4j.Logger;  

   import org.apache.log4j.PropertyConfigurator;  

   import org.openqa.selenium.By;  

   import org.openqa.selenium.NoSuchElementException;  

   import org.openqa.selenium.WebDriver;  

   import org.openqa.selenium.WebElement;  

   import org.testng.annotations.Test;  

public class testLogin {

public static final org.apache.log4j.Logger Log = Logger.getLogger(testLogin.class);

public static void main(String[] args) 

          

            

           {

org.apache.log4j.BasicConfigurator.configure();

                                               PropertyConfigurator.configure("C:\\Users\\Neeraj.Bakhtani\\workspace\\FacebookPOM\\src\\com\\neeraj\\facebook\\properties\\log4j.properties");

LoginPage page=new LoginPage();

LandingPage lp=page.doLogin("testi@gmail.com","password");

Log.info("Website navigated"); 

           }
                                   }