initial commit

lottery-client-java-se/src/com/example/lottery/client/LotteryAsyncClient.java

@@ -0,0 +1,42 @@
+package com.example.lottery.client;
+
+import java.io.IOException;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+/**
+ * 
+ * @author Binnur Kurt <binnur.kurt@gmail.com>
+ *
+ */
+public class LotteryAsyncClient {
+
+	private static final String URL = "http://localhost:8001/lottery/api/v1/numbers?column=10";
+
+	public static void main(String[] args) throws IOException, InterruptedException {
+		var counter = new AtomicInteger(0);
+		var client = HttpClient.newHttpClient();
+		var request = HttpRequest.newBuilder().uri(URI.create(URL)).header("Accept", "application/json").build();
+
+		var start = System.currentTimeMillis();
+		for (var i = 0; i < 1_000; ++i) {
+			// asynchronous call
+			client.sendAsync(request, HttpResponse.BodyHandlers.ofString()).thenApply(HttpResponse::body)
+					.thenAccept(numbers -> {
+						// System.out.println(Thread.currentThread().getName());
+						var value = counter.incrementAndGet();
+						if (value == 1_000) {
+							var stop = System.currentTimeMillis();
+							System.err.println("Duration: " + (stop - start) + " ms.");
+						}
+					}); // functional programming
+			// System.out.println(numbers);
+		}
+		TimeUnit.SECONDS.sleep(10);
+	}
+
+}

lottery-client-java-se/src/com/example/lottery/client/LotterySyncClient.java

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+package com.example.lottery.client;
+
+import java.io.IOException;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.util.stream.IntStream;
+
+/**
+ * 
+ * @author Binnur Kurt <binnur.kurt@gmail.com>
+ *
+ */
+public class LotterySyncClient {
+
+	private static final String URL = "http://localhost:8001/lottery/api/v1/numbers?column=10";
+
+	public static void main(String[] args) throws IOException, InterruptedException {
+		var client = HttpClient.newHttpClient();
+		var request = HttpRequest.newBuilder().uri(URI.create(URL)).header("Accept", "application/json").build();
+		var start = System.currentTimeMillis();
+		IntStream.range(0, 1_000).parallel().forEach(i -> {
+			// synchronous call
+			try {
+				// System.out.println(Thread.currentThread().getName());
+				client.send(request, HttpResponse.BodyHandlers.ofString()).body();
+			} catch (IOException | InterruptedException e) {
+				e.printStackTrace();
+			}
+			// System.out.println(numbers);
+		});
+		var stop = System.currentTimeMillis();
+		System.err.println("Duration: " + (stop - start) + " ms.");
+	}
+
+}

lottery-consumer-service/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.3.1.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>lottery-consumer-service</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>lottery-consumer-service</name>
+	<description>Spring Boot Project for Lottery Consumer  MicroService </description>
+
+	<properties>
+		<java.version>11</java.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.retry</groupId>
+			<artifactId>spring-retry</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>io.github.resilience4j</groupId>
+			<artifactId>resilience4j-spring-boot2</artifactId>
+			<version>1.5.0</version>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-actuator</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-devtools</artifactId>
+			<scope>runtime</scope>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+			<exclusions>
+				<exclusion>
+					<groupId>org.junit.vintage</groupId>
+					<artifactId>junit-vintage-engine</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>
+				spring-cloud-starter-netflix-eureka-client
+			</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-starter-openfeign</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>
+				spring-cloud-starter-netflix-hystrix
+			</artifactId>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+	<dependencyManagement>
+		<dependencies>
+			<dependency>
+				<groupId>org.springframework.cloud</groupId>
+				<artifactId>spring-cloud-dependencies</artifactId>
+				<version>Hoxton.SR5</version>
+				<type>pom</type>
+				<scope>import</scope>
+			</dependency>
+		</dependencies>
+	</dependencyManagement>
+</project>

lottery-consumer-service/src/main/java/com/example/lottery/LotteryConsumerServiceApplication.java

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+package com.example.lottery;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
+import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
+import org.springframework.cloud.netflix.hystrix.EnableHystrix;
+import org.springframework.cloud.openfeign.EnableFeignClients;
+import org.springframework.retry.annotation.EnableRetry;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+/**
+ * 
+ * @author Binnur Kurt <binnur.kurt@gmail.com>
+ *
+ */
+@SpringBootApplication
+@EnableScheduling
+@EnableEurekaClient
+@EnableDiscoveryClient
+@EnableFeignClients
+@EnableHystrix
+@EnableRetry
+public class LotteryConsumerServiceApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(LotteryConsumerServiceApplication.class, args);
+	}
+
+}

lottery-consumer-service/src/main/java/com/example/lottery/client/FallbackLotteryService.java

@@ -0,0 +1,19 @@
+package com.example.lottery.client;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import org.springframework.stereotype.Service;
+
+import com.example.lottery.dto.LotteryResponse;
+
+@Service
+public class FallbackLotteryService implements LotteryService {
+
+	@Override
+	public LotteryResponse getLotteryNumbers(int column) {
+		return new LotteryResponse(IntStream.range(0, column).mapToObj(i -> List.of(1,2,3,4,5,6)).collect(Collectors.toList()));
+	}
+
+}

lottery-consumer-service/src/main/java/com/example/lottery/client/LotteryService.java

@@ -0,0 +1,13 @@
+package com.example.lottery.client;
+
+import org.springframework.cloud.openfeign.FeignClient;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+
+import com.example.lottery.dto.LotteryResponse;
+
+@FeignClient(name="lottery",fallback = FallbackLotteryService.class)
+public interface LotteryService {
+	@GetMapping("/lottery/api/v1/numbers")
+	LotteryResponse getLotteryNumbers(@RequestParam int column);
+}

lottery-consumer-service/src/main/java/com/example/lottery/config/RestTemplateConfig.java

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+package com.example.lottery.config;
+
+import org.springframework.cloud.client.loadbalancer.LoadBalanced;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.web.client.RestTemplate;
+
+/**
+ * 
+ * @author Binnur Kurt <binnur.kurt@gmail.com>
+ *
+ */
+@Configuration
+public class RestTemplateConfig {
+
+	@Bean
+	@LoadBalanced
+	public RestTemplate restTemplate() {
+		return new RestTemplate();
+	}
+}

lottery-consumer-service/src/main/java/com/example/lottery/dto/LotteryResponse.java

@@ -0,0 +1,33 @@
+package com.example.lottery.dto;
+
+import java.util.List;
+
+/**
+ * 
+ * @author Binnur Kurt <binnur.kurt@gmail.com>
+ *
+ */
+public class LotteryResponse {
+	private List<List<Integer>> numbers;
+
+	public LotteryResponse() {
+	}
+
+	public LotteryResponse(List<List<Integer>> numbers) {
+		this.numbers = numbers;
+	}
+
+	public List<List<Integer>> getNumbers() {
+		return numbers;
+	}
+
+	public void setNumbers(List<List<Integer>> numbers) {
+		this.numbers = numbers;
+	}
+
+	@Override
+	public String toString() {
+		return "LotteryResponse [numbers=" + numbers + "]";
+	}
+
+}

lottery-consumer-service/src/main/java/com/example/lottery/service/LotteryConsumerServiceLoadBalancing1.java

@@ -0,0 +1,47 @@
+package com.example.lottery.service;
+
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import javax.annotation.PostConstruct;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.cloud.client.ServiceInstance;
+import org.springframework.cloud.client.discovery.DiscoveryClient;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Service;
+import org.springframework.web.client.RestTemplate;
+
+import com.example.lottery.dto.LotteryResponse;
+
+/**
+ * 
+ * @author Binnur Kurt <binnur.kurt@gmail.com>
+ *
+ */
+@Service
+public class LotteryConsumerServiceLoadBalancing1 {
+	private static final String LOTTERY_SERVICE_URL = "http://%s:%d/lottery/api/v1/numbers?column=10";
+
+	@Autowired
+	private DiscoveryClient discoveryClient;
+	private List<ServiceInstance> servers;
+	private AtomicInteger counter = new AtomicInteger(0);
+	private RestTemplate restTemplate;
+
+	@PostConstruct
+	public void loadInstanceList() {
+		servers = discoveryClient.getInstances("lottery");
+		servers.forEach(System.out::println);
+		this.restTemplate = new RestTemplate();
+	}
+
+	@Scheduled(fixedRate = 3_000)
+	public void callLotteryService() {
+		var index = counter.getAndIncrement() % servers.size();
+		var server = servers.get(index);
+		var url = String.format(LOTTERY_SERVICE_URL, server.getHost(), server.getPort());
+		var response = restTemplate.getForObject(url, LotteryResponse.class);
+		System.out.println(response);
+	}
+}