Selenium 4 Features – Retrieving Browser Console Log Using Selenium WebDriver

Selenium 4 is out ( Alpha version at the time of writing this post). They have given a very important feature in Selenium 4 which is Logging. Logging is generally helpful to know what went wrong.

When you launch a website in browser, you can see logs in console tab of Developer tool. These logs are important to find bugs which may be missed by manual testers or automation tests. Red color logs are Errors while yellow colored logs are Warnings.

Now it is possible to capture these logs using Selenium and we can analyse these logs to find missed bugs. Developers will also get a better idea from these logs. This log type is called Browser level.

Selenium WebDriver is providing five log types as of now:-

1. Browser:- Javascript console logs from the browser
2. Client :- Logs from the client side implementation of the WebDriver protocol (e.g. the Java bindings)
3. Driver:- Logs from the internals of the driver (e.g. FirefoxDriver internals)
4. Performance :- Logs relating to the performance characteristics of the page under test (e.g. resource load timings)
5. Server :- Logs from within the selenium server.

In this example we are focusing on Browser level Log type. Below are some important points:-

• LogType is a class which provides you static final constants such as to pass log type.
• LogEntries is a class which is iterable which consists log details.
• Option inner interface of WebDriver interface consists “logs()” methods. We can access it using driver.manage().logs()

Program:-

package Selenium4Features;

import java.awt.AWTException;
import java.util.List;

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.logging.LogEntries;
import org.openqa.selenium.logging.LogEntry;
import org.openqa.selenium.logging.LogType;

import io.github.bonigarcia.wdm.WebDriverManager;

public class ConsoleLog {
	
	public static void main(String[] args) throws AWTException {
		
		// Setting chrome executable
		WebDriverManager.chromedriver().setup();
		// Launching browser
        WebDriver driver = new ChromeDriver();
        // Loading URL
        driver.get("http://makeseleniumeasy.com/");
        // Mentioning type of Log 
        LogEntries entry = driver.manage().logs().get(LogType.BROWSER);
        // Retrieving all log 
        List logs= entry.getAll();
        // Print one by one
        for(LogEntry e: logs)
        {
        	System.out.println(e);
        }
        
        // Printing details separately 
        for(LogEntry e: logs)
        {
        	System.out.println("Message is: " +e.getMessage());
        	System.out.println("Level is: " +e.getLevel());
        }
       
        
        
	}

}

Output:-

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
Starting ChromeDriver 78.0.3904.105 (60e2d8774a8151efa6a00b1f358371b1e0e07ee2-refs/branch-heads/3904@{#877}) on port 22084
Only local connections are allowed.
Please protect ports used by ChromeDriver and related test frameworks to prevent access by malicious code.
[1576137115.752][WARNING]: Timed out connecting to Chrome, retrying...
Dec 12, 2019 1:21:57 PM org.openqa.selenium.remote.ProtocolHandshake createSession
INFO: Detected dialect: W3C
[2019-12-12T13:21:59+0530] [SEVERE] http://makeseleniumeasy.com/wp-content/plugins/email-subscribe/js/subscribe-popup.js?ver=5.1.3 1101:20 Uncaught TypeError: Cannot read property 'css' of undefined
[2019-12-12T13:21:59+0530] [SEVERE] http://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js 42:397 Uncaught N: adsbygoogle.push() error: Fluid responsive ads must be at least 250px wide: availableWidth=220
Message is: http://makeseleniumeasy.com/wp-content/plugins/email-subscribe/js/subscribe-popup.js?ver=5.1.3 1101:20 Uncaught TypeError: Cannot read property 'css' of undefined
Level is: SEVERE
Message is: http://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js 42:397 Uncaught N: adsbygoogle.push() error: Fluid responsive ads must be at least 250px wide: availableWidth=220
Level is: SEVERE

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