Kill process in Windows & Linux

Windows:

> netstat -ano | findstr :8080

> taskkill PID <pid> /F

Linux:

> sudo lsof -i 8080

> sudo kill -9 <pid>

Proto vs Json performance test

 

public class PerformanceTest {
    private static final Logger LOGGER = LoggerFactory.getLogger(PerformanceTest.class);
    private static final ObjectMapper MAPPER = new ObjectMapper();

    public static void main(String[] args) throws Exception {
        var protoPerson = Person.newBuilder()
                .setLastName("T")
                .setAge(32)
                .setEmail("t@email.com")
                .setEmployed(true)
                .setSalary(123004.5)
                .setBankAccountNumber(38495959093040944L)
                .setBalance(-100)
                .build();
        LOGGER.info("how many bytes protoPerson has? {}", protoPerson.toByteArray().length); // 41

        var jsonPerson = new JsonPerson("T", 32, "t@email.com", true, 123004.5, 38495959093040944L, -100);
        var bytes = MAPPER.writeValueAsBytes(jsonPerson);
        LOGGER.info("how many bytes jsonPerson has? {}", bytes.length); // 130 = 3x more!

        for (int i=0; i<5; i++) { // first run to be ignored (warmup JVM)
            runTest("json", () -> json(jsonPerson));
            runTest("proto", () -> proto(protoPerson));  // 7x faster!
        }
    }

    private static void runTest(String testName, Runnable runnable) {
        var start = System.currentTimeMillis();
        for (int i=0; i<5_000_000; i++) {
            runnable.run();
        }
        var end = System.currentTimeMillis();
        LOGGER.info("time taken for {} = {} ms", testName, (end - start));
    }

    private static void proto(Person person)  {
        try {
            var bytes = person.toByteArray();
            Person.parseFrom(bytes);
        } catch (InvalidProtocolBufferException e) {
            throw new RuntimeException(e);
        }
    }

    private static void json(JsonPerson person) {
        try {
            var bytes = MAPPER.writeValueAsBytes(person);
            MAPPER.readValue(bytes, JsonPerson.class);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }
}

Implementarea unui Rate Limiter

public class RateLimiter {
    private static final int ONE_SECOND = 1000;
    private final Map<String, List<Long>> requests;
    private boolean enabled = false;
    private int requestsPerSecond;

    public RateLimiter(Environment environment) {
        requests = new HashMap<>();
        if (environment.getProperty("enable.rate.limiter") != null) {
            this.enabled = Boolean.parseBoolean(environment.getProperty("enable.rate.limiter"));
        }
        if (this.enabled) {
            String property = environment.getProperty("max.requests.per.user.per.second");
            Assert.notNull(property, "Max requests per second not defined!");
            this.requestsPerSecond = Integer.parseInt(property);
        }
    }

    public boolean allows(String ipAddress) {
        if (!enabled) {
            return true;
        }

        if (!requests.containsKey(ipAddress)) {
            requests.put(ipAddress, new ArrayList<>());
        }

        Long now = System.currentTimeMillis();
        cleanup(ipAddress, now);
        requests.get(ipAddress).add(now);

        return requests.get(ipAddress).size() <= requestsPerSecond;
    }

    private void cleanup(String ipAddress, Long now) {
        List<Long> markedForDeletion = new ArrayList<>();
        for (Long timestamp : requests.get(ipAddress)) {
            if (now - timestamp > ONE_SECOND) {
                markedForDeletion.add(timestamp);
            }
        }
        requests.get(ipAddress).removeAll(markedForDeletion);
    }
}

Test de integrare pt Kafka Consumer

@EmbeddedKafka
@SpringBootTest(properties = "spring.kafka.consumer.bootstrap-servers=${spring.embedded.kafka.brokers}")
public class ProductCreatedEventHandlerTest {
    @MockBean
    ProcessedEventRepository processedEventRepository;

    @Autowired
    KafkaTemplate<String, Object> kafkaTemplate;

    @SpyBean // true object, its methods can be intercepted
    ProductCreatedEventHandler productCreatedEventHandler;

    @Test
    public void testHandle() throws Exception {
        // Arrange
        ProductCreatedEvent event = new ProductCreatedEvent(UUID.randomUUID().toString(), "iPhone SE", BigDecimal.valueOf(24.5), 12);
        ProducerRecord<String, Object> record = new ProducerRecord<>(PRODUCT_CREATED_EVT_TOPIC, event.getProductId(), event);
        String messageId = UUID.randomUUID().toString();
        record.headers().add("messageId", messageId.getBytes());
        record.headers().add(KafkaHeaders.RECEIVED_KEY, event.getProductId().getBytes());

        ProcessedEventEntity processedEventEntity = new ProcessedEventEntity();
        when(processedEventRepository.findByMessageId(any())).thenReturn(processedEventEntity);

        // Act
        kafkaTemplate.send(record).get();

        // Assert
        ArgumentCaptor<String> messageIdCaptor = ArgumentCaptor.forClass(String.class);
        ArgumentCaptor<String> messageKeyCaptor = ArgumentCaptor.forClass(String.class);
        ArgumentCaptor<ProductCreatedEvent> eventCaptor = ArgumentCaptor.forClass(ProductCreatedEvent.class);
        verify(productCreatedEventHandler, timeout(5000).times(1))
                .handle(eventCaptor.capture(), messageIdCaptor.capture(), messageKeyCaptor.capture());
        Assertions.assertEquals(messageId, messageIdCaptor.getValue());
        Assertions.assertEquals(event.getProductId(), messageKeyCaptor.getValue());
        Assertions.assertEquals(event.getProductId(), eventCaptor.getValue().getProductId());
    }
}

Test de integrare pt Kafka Producer

1. Testarea serviciului care trimite mesaje Kafka

package com.hanul.pis.ProductsMicroservice;

import com.hanul.pis.ProductsMicroservice.rest.NewProductDto;
import com.hanul.pis.ProductsMicroservice.service.ProductService;
import com.hanul.pis.core.event.ProductCreatedEvent;
import org.apache.kafka.clients.consumer.ConsumerConfig;
import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.common.serialization.StringDeserializer;
import org.junit.jupiter.api.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.core.env.Environment;
import org.springframework.kafka.core.DefaultKafkaConsumerFactory;
import org.springframework.kafka.listener.ContainerProperties;
import org.springframework.kafka.listener.KafkaMessageListenerContainer;
import org.springframework.kafka.listener.MessageListener;
import org.springframework.kafka.support.serializer.ErrorHandlingDeserializer;
import org.springframework.kafka.support.serializer.JsonDeserializer;
import org.springframework.kafka.test.EmbeddedKafkaBroker;
import org.springframework.kafka.test.context.EmbeddedKafka;
import org.springframework.kafka.test.utils.ContainerTestUtils;
import org.springframework.test.annotation.DirtiesContext;
import org.springframework.test.context.ActiveProfiles;

import java.math.BigDecimal;
import java.util.Map;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.TimeUnit;

@DirtiesContext                                 // it will corrupt the application context -> each test will start with a clean state
@TestInstance(TestInstance.Lifecycle.PER_CLASS) // one instance for all test methods, for expensive setup code
@ActiveProfiles("test")                         // look for application-test.properties
// use embedded Kafka server
@EmbeddedKafka (partitions = 3, count = 3, controlledShutdown = true)
@SpringBootTest(properties = "spring.kafka.producer.bootstrap-servers=${spring.embedded.kafka.brokers}")
public class ProductServiceImplTest {
    @Autowired
    private ProductService productService;

    @Autowired
    private EmbeddedKafkaBroker embeddedKafkaBroker;

    @Autowired
    private Environment environment;

    private KafkaMessageListenerContainer<String, ProductCreatedEvent> container;
    private BlockingQueue<ConsumerRecord<String, ProductCreatedEvent>> records = new LinkedBlockingQueue<>();

    @BeforeAll
    void setUp() {
        Map<String, Object> consumerProperties = getConsumerProperties();
        DefaultKafkaConsumerFactory<String, Object> consumerFactory = new DefaultKafkaConsumerFactory<>(consumerProperties);
        ContainerProperties containerProperties = new ContainerProperties(environment.getProperty("product-created-evt-topic-name"));
        container = new KafkaMessageListenerContainer<>(consumerFactory, containerProperties);
        container.setupMessageListener((MessageListener<String, ProductCreatedEvent>) records::add);
        container.start();
        ContainerTestUtils.waitForAssignment(container, embeddedKafkaBroker.getPartitionsPerTopic());
    }

    @AfterAll
    void tearDown() {
        container.stop();
    }

    @Test
    void testCreateProduct_validProduct_success() throws Exception {
        // Arrange
        NewProductDto newProductDto = new NewProductDto();
        newProductDto.setPrice(new BigDecimal(1200));
        newProductDto.setQuantity(10);
        newProductDto.setTitle("Philips monitor 40\"");

        // Act
        String productId = productService.createProduct(newProductDto);

        // Assert
        Assertions.assertNotNull(productId);
        ConsumerRecord<String, ProductCreatedEvent> message = records.poll(3, TimeUnit.SECONDS);
        Assertions.assertNotNull(message);
        Assertions.assertNotNull(message.key());
        ProductCreatedEvent event = message.value();
        Assertions.assertNotNull(event);
        Assertions.assertEquals(newProductDto.getTitle(), event.getTitle());
        Assertions.assertEquals(newProductDto.getPrice(), event.getPrice());
        Assertions.assertEquals(newProductDto.getQuantity(), event.getQuantity());
    }

    private Map<String, Object> getConsumerProperties() {
        // Brokers' port numbers will dynamically change during executions of this test
        // Therefore, they should be dynamically retrieved in configuration
        return Map.of(
                ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, embeddedKafkaBroker.getBrokersAsString(),
                ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class,
                ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, ErrorHandlingDeserializer.class,
                ErrorHandlingDeserializer.VALUE_DESERIALIZER_CLASS, JsonDeserializer.class,
                ConsumerConfig.GROUP_ID_CONFIG, environment.getProperty("spring.kafka.consumer.group-id"),
                JsonDeserializer.TRUSTED_PACKAGES, environment.getProperty("spring.kafka.consumer.properties.spring.json.trusted.packages"),
                ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, environment.getProperty("spring.kafka.consumer.auto-offset-reset")
                );
    }
}

2. Testarea configurarilor - ex. ca producatorul este idempotent

package com.hanul.pis.ProductsMicroservice;

import com.hanul.pis.core.event.ProductCreatedEvent;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.kafka.core.KafkaTemplate;
import org.springframework.kafka.core.ProducerFactory;

import java.util.Map;

@SpringBootTest
public class IdempotentProducerItTest { // it will test based on real configuration
    @Autowired
    KafkaTemplate<String, ProductCreatedEvent> kafkaTemplate;

    @Test
    void test_enabledIdempotence() {
        // Arrange
        ProducerFactory<String, ProductCreatedEvent> producerFactory = kafkaTemplate.getProducerFactory();

        // Act
        Map<String, Object> config = producerFactory.getConfigurationProperties();

        // Assert
        Assertions.assertEquals("true", config.get(ProducerConfig.ENABLE_IDEMPOTENCE_CONFIG));
        Assertions.assertTrue("all".equalsIgnoreCase((String) config.get(ProducerConfig.ACKS_CONFIG)));
        if (config.containsKey(ProducerConfig.RETRIES_CONFIG)) {
            Assertions.assertTrue(Integer.parseInt(config.get(ProducerConfig.RETRIES_CONFIG).toString()) > 0);
        }
    }
}