Cucumber - Custom Plugins

Cucumber provides support for creating custom plugins to extend its functionality and tailor the testing framework to meet specific project needs. Custom plugins allow developers to integrate Cucumber with external systems, generate custom reports, or add specific hooks and filters.

Why Use Custom Plugins?

To create custom reports that suit stakeholders' requirements.
To integrate with proprietary tools or APIs.
To manage custom logging or data extraction during test runs.
To enforce specific project standards by applying rules or validations.

Real-World Scenario

Consider a scenario where an organization needs a tailored report that highlights only failed test cases with screenshots of the application at the time of failure. Out-of-the-box reporting plugins may not provide this functionality. By creating a custom plugin, developers can write logic to collect failure-specific details and embed screenshots in the generated report.

Example of a Custom Plugin

Here’s a simple example of a custom plugin to log execution time for each test step:


              // Import necessary Cucumber classes
              import io.cucumber.plugin.ConcurrentEventListener;
              import io.cucumber.plugin.event.EventPublisher;
              import io.cucumber.plugin.event.TestStepStarted;
              import io.cucumber.plugin.event.TestStepFinished;
              
              public class ExecutionTimeLoggerPlugin implements ConcurrentEventListener {
              
                  private long startTime;
              
                  @Override
                  public void setEventPublisher(EventPublisher publisher) {
                      publisher.registerHandlerFor(TestStepStarted.class, this::handleTestStepStarted);
                      publisher.registerHandlerFor(TestStepFinished.class, this::handleTestStepFinished);
                  }
              
                  private void handleTestStepStarted(TestStepStarted event) {
                      startTime = System.currentTimeMillis();
                      System.out.println("Step started: " + event.getTestStep().getCodeLocation());
                  }
              
                  private void handleTestStepFinished(TestStepFinished event) {
                      long endTime = System.currentTimeMillis();
                      System.out.println("Step finished. Execution time: " + (endTime - startTime) + "ms");
                  }
              }

How to Use This Plugin

Compile the plugin and include it in your project’s dependencies.
Register the plugin in the cucumber.properties file or through command-line arguments:
```
--plugin com.example.plugins.ExecutionTimeLoggerPlugin
```
Run your tests, and observe the execution times logged in the console.

Benefits of Custom Plugins

Enhance test reporting for better insights.
Enable seamless integration with other tools and systems.
Provide flexibility to meet unique testing requirements.