Unable to get Chrome Performance logs in Selenium C#

Question

I am using following nuget packages in my solution

1. Selenium.WebDriver - v3.141.0
2. Selenium.WebDriver.ChromeDriver - v79.0.3945.3600

using following code I am creating a Chrome driver instance

ChromeOptions options = new ChromeOptions();

//Get Performance Logs from Network tab
ChromePerformanceLoggingPreferences perfLogPrefs = new ChromePerformanceLoggingPreferences();
options.PerformanceLoggingPreferences = perfLogPrefs;
options.SetLoggingPreference("performance", LogLevel.All);

(or)

ChromePerformanceLoggingPreferences perfLogPrefs = new 
ChromePerformanceLoggingPreferences();
perfLogPrefs.AddTracingCategories(new string[] { "devtools.timeline" });
options.PerformanceLoggingPreferences = perfLogPrefs;
options.SetLoggingPreference("goog:loggingPrefs", LogLevel.All);
options.AddAdditionalCapability(CapabilityType.EnableProfiling, true, true);

and combining with this

options.AddUserProfilePreference("intl.accept_languages", "en-US");
options.AddUserProfilePreference("disable-popup-blocking", "true");
options.AddArgument("test-type");
options.AddArgument("--disable-gpu");
options.AddArgument("no-sandbox");
options.AddArgument("start-maximized");
options.LeaveBrowserRunning = true;

IWebDriver driver = new ChromeDriver(options);

but while creating Chrome driver instance, I am getting following error message

invalid argument: entry 0 of 'firstMatch' is invalid from invalid argument: perfLoggingPrefs specified, but performance logging was not enabled

May I know what changes do I need to make please to get the performance logs with latest version of Chrome and Selenium driver

I am able to retrieve Performance Logs using the below code when I was using lower versions of Chrome driver (2.35.0)

var logs = driver.Manage().Logs.GetLog("performance");

for (int i = 0; i < logs.Count; i++)
{
   Console.WriteLine(logs[i].Message);
}

Answer 1

With Selenium WebDriver (v4.0.0-alpha04) and Selenium.Chrome.WebDriver (v79.0.0) and using the following code, I am able to retrieve the performance logs.

ChromeOptions options = new ChromeOptions();

//Following Logging preference helps in enabling the performance logs
options.SetLoggingPreference("performance", LogLevel.All);

//Based on your need you can change the following options
options.AddUserProfilePreference("intl.accept_languages", "en-US");
options.AddUserProfilePreference("disable-popup-blocking", "true");
options.AddArgument("test-type");
options.AddArgument("--disable-gpu");
options.AddArgument("no-sandbox");
options.AddArgument("start-maximized");
options.LeaveBrowserRunning = true;

//Creating Chrome driver instance
IWebDriver driver = new ChromeDriver(options);

//Extracting the performance logs
var logs = driver.Manage().Logs.GetLog("performance");
for (int i = 0; i < logs.Count; i++)
{
   Console.WriteLine(logs[i].Message);
}

Hope this helps.

All these days, I was using the following two lines with latest versions of Selenium WebDriver and Chrome Driver and couldn't figure out what the issue was and now with the latest versions, the following two lines of code is not required.

var perfLogPrefs = new ChromePerformanceLoggingPreferences();
options.PerformanceLoggingPreferences = perfLogPrefs;