Test Listeners allow you to hook your custom code for performing various actions. The listener can perform some actions or track details before/after command execution as well as on failure.

It provides flexibility to expand the scope of testing. You can define your own criteria to create Test Listeners and execute them on fulfilling mentioned conditions.

Test Listeners for Java/QAF, Java/Cucumber, Java/TestNG Frameworks

Automation Listeners

You can create listener by implementing appropriate listener interface of by extending appropriate adapter class. To register one or more listener you need to set appropriate property.

Listeners API Table

List Interface	Adapter Class	Property	Listener Methods
QAFDataProviderIntercepter	QAFListenerAdapter	qaf.listeners	beforeFech(TestNGScenario, ITestContext)
			List intercept(TestNGScenario, ITestContext, List<java.lang.Object[]>)
QAFTestStepListener	QAFTestStepAdapter	teststep.listeners or qaf.listeners	onFailure(StepExecutionTracker)
			beforExecute(StepExecutionTracker)
			afterExecute(StepExecutionTracker)
QAFWebDriverCommandListener	QAFWebDriverCommandAdapter	wd.command.listeners or qaf.listeners	beforeInitialize(Capabilities)
			onInitialize(QAFExtendedWebDriver)
			beforeCommand(QAFExtendedWebDriver, CommandTracker)
			afterCommand(QAFExtendedWebDriver, CommandTracker)
			onFailure(QAFExtendedWebDriver, CommandTracker)
			onInitializationFailure(Capabilities desiredCapabilities, Throwable t)
QAFWebElementCommandListener	QAFWebElementCommandAdapter	we.command.listeners or qaf.listeners	beforeCommand(QAFExtendedWebElement, CommandTracker)
			afterCommand(QAFExtendedWebElement, CommandTracker)
			onFailure(QAFExtendedWebElement, CommandTracker)

There is additional Adapter Class QAFListenerAdapter that implements all of the qaf listeners. You can extend it, override required methods and register using qaf.listeners property.

TestStep Listener

In order to create teststep listener, you need to implement listener interface com.qmetry.qaf.automation.step.QAFTestStepListener or extend adapter class QAFTestStepAdapter.

QAFTestStepListener defines following methods:

void beforExecute(StepExecutionTracker stepExecutionTracker); 
void afterExecute(StepExecutionTracker stepExecutionTracker); 
void onFailure(StepExecutionTracker stepExecutionTracker);

Creating Listener

public class ThresholdListener extends QAFTestStepAdapter {
    @Override
    public void afterExecute(StepExecutionTracker stepExecutionTracker) {
        long duration = (stepExecutionTracker.getEndTime() - stepExecutionTracker.getStartTime()) / 1000;
        if (stepExecutionTracker.getStep().getThreshold() > duration)
            stepExecutionTracker.setVerificationError("Threshold value is exceeded");
    }
}

Registering listener

To register listener set property teststep.listeners.

For example to register above created listener you need to set property as below:

teststep.listeners=com.qmetry.qaf.listeners.ThresholdListener

WebDriver Listener

In order to create webdriver command listener, you need to implement listener interfaceQAFWebDriverCommandListeneror extend adapter classQAFWebDriverCommandAdapter.

QAFWebDriverCommandListenerdefines following methods:

void beforeInitialize(Capabilities)
void beforeCommand(QAFExtendedWebDriver paramQAFExtendedWebDriver, CommandTracker paramCommandTracker);
void afterCommand(QAFExtendedWebDriver paramQAFExtendedWebDriver, CommandTracker paramCommandTracker);
void onFailure(QAFExtendedWebDriver paramQAFExtendedWebDriver, CommandTracker paramCommandTracker);
void onInitialize(QAFExtendedWebDriver driver);

Creating listener

public class WDListener extends QAFWebDriverCommandAdapter {
    Log logger = LogFactory.getLog(getClass());
    @Override
    public void beforeCommand(QAFExtendedWebDriver driver, CommandTracker commandTracker) {
        super.beforeCommand(driver, commandTracker);
        String command = commandTracker.getCommand();
        Map<String, Object> params = commandTracker.getParameters();
        // support selenium 1 api for navigating from frame to main window
        // with selenium.selectFrame("");
        if (command.equalsIgnoreCase(DriverCommand.SWITCH_TO_FRAME) && StringUtil.isBlank((String) params.get("id"))) {
            String mainWindow = driver.getWindowHandle();
            params.put("id", mainWindow);
            driver.switchTo().window(mainWindow);
            // skip original command execution
            commandTracker.setResponce(new Response());
        }
        if (command.equalsIgnoreCase(DriverCommand.SWITCH_TO_WINDOW)) {
            String targetWindow = String.valueOf(commandTracker.getParameters().get("name"));
            String parentHandle = driver.getWindowHandle();
            if (!targetWindow.equalsIgnoreCase(parentHandle)) {
                // store the parent window handle
                ConfigurationManager.getBundle().setProperty("parentWindowHandel", parentHandle);
            }
        }
    }
    @Override
    public void onFailure(QAFExtendedWebDriver driver, CommandTracker commandTracker) {
        super.onFailure(driver, commandTracker);
        if (commandTracker.getCommand().equalsIgnoreCase(DriverCommand.SWITCH_TO_WINDOW)
                && commandTracker.hasException()) {
            Set<String> windows = driver.getWindowHandles();
            String parentWindowHandel = ConfigurationManager.getBundle().getString("parentWindowHandel");
            for (String window : windows) {
                if (!parentWindowHandel.equalsIgnoreCase(window)) {
                    driver.switchTo().window(window);
                    // now we can remove the exception, it is handled!
                    commandTracker.setException(null);
                    break;
                }
            }
        }
    }
}

Registering listener

To register listener set property wd.command.listeners. For example to register above created listener you need to set property as below:

wd.command.listeners= com.ispl.automation.sample.webdriver.WDListener

WebElement Listener

A simple but very useful example of listener is “listener for sendkeys”. As you know in webdriver send keys will append the text box, so each time we need to first call clear command and then use send keys command.

Code Without listener:

firstName.clear();
firstName.sendKeys("fname");
lastName.clear();
firstName.sendKeys("lname");

Code With use of listener:

firstName.sendKeys("fname");
firstName.sendKeys("lname");

Creating listener:

In order to create webelement command listener, you need to implement listener interface QAFWebElementCommandListener or extend adapter class QAFWebElementCommandAdapter.

QAFWebElementCommandListener defines following methods:

void beforeCommand(QAFExtendedWebElement paramQAFExtendedWebElement, CommandTracker paramCommandTracker);
void afterCommand(QAFExtendedWebElement paramQAFExtendedWebElement, CommandTracker paramCommandTracker);
void onFailure(QAFExtendedWebElement paramQAFExtendedWebElement, CommandTracker paramCommandTracker);

Below example illustrates how we can write a listener that clears element text before sending text.

public class SendKeysListener extends QAFWebElementCommandAdapter {
    @Override
    public void beforeCommand(QAFExtendedWebElement element, CommandTracker commandTracker) {
        if (commandTracker.getCommand().equalsIgnoreCase(DriverCommand.SEND_KEYS_TO_ELEMENT)) {
            element.clear();
            // you access/modify any parameter!
            String value = String.valueOf(commandTracker.getParameters().get("value"));
            if (StringUtil.isBlank(value)) {
                // No need to send key
                // ignore actual command
                commandTracker.setResponce(new Response());
            }
        }
    }
}

In this example we had extended adapter class for webelement command listener and provided implementation for beforeCommand. Same way you can provide implementation for afterCommand and onFailure method if required. You can see that one can access parameters in listener and also can modify its value if required.

Registering listener

To register listener set property we.command.listeners. For example to register above created listener you need to set property as below:

we.command.listeners= com.ispl.automation.sample.webdriver.SendKeysListener

TestNG Listeners

One can create and use different kind of TestNG listeners. Please refer TestNG documentation for more information and examples.

Test Listeners for Python/Behave

In Behave, listeners are often referred as hooks.

Automation Listeners

In resources/application.properties file you can mention your test listener python classes.

e.g.

wd.command.listeners=model.listener.Listener
we.command.listeners=model.listener.ElementListener

There are two types of Automation Listeners

WebDriver Event Listener

WebDriver Event Listener - specify using `wd.command.listeners` key, separated by ';'
Listener class should extend/implement below methods.

def before_command(self, driver, command_tracker):
# your implmentation to be performed before command goes here
pass

def after_command(self, driver, command_tracker):
# your implmentation to be performed after command goes here
pass

def on_exception(self, driver, command_tracker):
# your implmentation to be performed when some exception occurs goes here
pass

Example of such listener is attached here: wd_listener.py

WebElement Event Listener

WebElement Event Listener - specify using `we.command.listeners` key, separated by ';'
Listener class should extend/implement below methods

def before_command(self, driver, command_tracker):
# your implmentation to be performed before command goes here
pass

def after_command(self, driver, command_tracker):
# your implmentation to be performed after command goes here
pass

def on_exception(self, driver, command_tracker):
# your implmentation to be performed when some exception occurs goes here
pass

Example of such listener is attached here: we_listener.py

Behave Listeners

One can create and use different kind of Behave listeners. Refer to Behave documentation for more information and examples.
One such listener/hook is environment.py file, which controls the driver management and execution.