LoggingTestExtension.java

package fr.sii.ogham.testing.extension.junit;

import java.util.Optional;

import org.junit.jupiter.api.extension.AfterEachCallback;
import org.junit.jupiter.api.extension.BeforeAllCallback;
import org.junit.jupiter.api.extension.BeforeEachCallback;
import org.junit.jupiter.api.extension.ExtensionContext;
import org.junit.jupiter.api.extension.RegisterExtension;
import org.junit.platform.commons.support.AnnotationSupport;

import fr.sii.ogham.testing.extension.common.LogTestInformation;
import fr.sii.ogham.testing.extension.common.Printer;
import fr.sii.ogham.testing.extension.common.TestInformationLogger;

/**
 * Write information about test. This is useful when there are many tests:
 * <ul>
 * <li>To quickly find the logs for the test</li>
 * <li>To quickly know if the test has failed or succeeded</li>
 * <li>To quickly identify the test failure</li>
 * <li>To quickly find failed tests</li>
 * </ul>
 * 
 * @author Aurélien Baudet
 *
 */
public class LoggingTestExtension implements BeforeEachCallback, AfterEachCallback, BeforeAllCallback {
    private TestInformationLogger logger;

    /**
     * No logger initialized (it will be initialized using annotation). If you
     * use {@link RegisterExtension} annotation, please use another constructor.
     * 
     */
    public LoggingTestExtension() {
        super();
    }

    /**
     * Initializes with the provided max line length.
     * 
     * Uses Slf4j logger and default marker ("test-info").
     * 
     * @param maxLength
     *            the length of each line
     */
    public LoggingTestExtension(int maxLength) {
        super();
        this.logger = new TestInformationLogger(maxLength);
    }

    /**
     * Initializes with the provided max line length and marker.
     * 
     * Uses Slf4j logger.
     * 
     * @param maxLength
     *            the length of each line
     * @param marker
     *            the marker for logs
     */
    public LoggingTestExtension(int maxLength, String marker) {
        super();
        this.logger = new TestInformationLogger(maxLength, marker);
    }

    /**
     * 
     * @param maxLength
     *            the length of each line
     * @param marker
     *            the marker for logs
     * @param logger
     *            the logger
     */
    public LoggingTestExtension(int maxLength, String marker, Printer logger) {
        super();
        this.logger = new TestInformationLogger(maxLength, marker, logger);
    }

    @Override
    public void beforeAll(ExtensionContext context) throws InstantiationException, IllegalAccessException {
        if (logger != null) {
            return;
        }
        LogTestInformation annotation = AnnotationSupport.findAnnotation(context.getElement(), LogTestInformation.class).orElse(null);
        if (annotation == null) {
            logger = new TestInformationLogger();
        } else {
            logger = new TestInformationLogger(annotation.maxLength(), annotation.marker(), annotation.printer().newInstance());
        }
    }

    @Override
    public void beforeEach(ExtensionContext context) throws Exception {
        logger.writeStart(context.getDisplayName());
    }

    @Override
    public void afterEach(ExtensionContext context) throws Exception {
        Optional<Throwable> executionException = context.getExecutionException();
        if (executionException.isPresent()) {
            logger.writeFailure(context.getDisplayName(), executionException.get());
        } else {
            logger.writeSuccess(context.getDisplayName());
        }
    }

}