Context

• This repository is a implementation level proof-of-concept aka POC supporting the fact, Reactive programming can provide better throughput with limited resources.
• The Project utilizes Spring-web and Spring-webflux frameworks in this POC.
• The Spring-web supports synchronus programming and the Spring-webflux supports a reactive (non-blocking) programming.
• The Spring-web uses a Tomcat server (default) which uses a thread-per-request model while Spring-webflux uses Netty server which uses concpets of non-blocking I/O (NIO).

Getting Started with Code exploration

Project Structure

• This is a mutli-module project built using POM build tool.
• The project contains 3 modules.
• Module library contains the DTOs.
• Module mvcapi is the Spring-web implementation.
• Module reactiveapi is the Spring-webflux implementation.

Configuring the thread-pool size of the servers

• Thread pool size of the server needs to be same to get a fair judgement of the performance. I have used 3.

• For Tomcat, we can do this by setting property in application.properties

  server.tomcat.threads.max=3
  

• For Netty server, we can do this by creating a customized ReactiveWebServerFactory bean

  @Bean
  	public ReactiveWebServerFactory reactiveWebServerFactory() {
  		NettyReactiveWebServerFactory factory = new NettyReactiveWebServerFactory();
  		factory.addServerCustomizers(builder -> builder.runOn(LoopResources.create("my-http", 3, true)));
  
  		return factory;
  	}
  

• The mvcapi & reactiveapi are configured to run on port 8001 and 8002 respectively.

• The request body parameter uses Request entitity as template.

  import java.time.LocalTime;
  
  import lombok.Data;
  
  
  @Data
  public class Request {
      private int id;
      private LocalTime creationTime;
  }
  
  

• The Application uses Message entitity as it's response template.

  import jakarta.persistence.Entity;
  import jakarta.persistence.GeneratedValue;
  import jakarta.persistence.GenerationType;
  import lombok.Getter;
  import lombok.NoArgsConstructor;
  import lombok.Setter;
  
  @Entity
  @Getter
  @Setter
  @NoArgsConstructor
  public class Message {
  
      @Id
      @GeneratedValue(strategy = GenerationType.AUTO)
      private int id;
      private int messageLength;
      private String message;
  }
  

Cloning the Repository

• Open the directory where you want to keep the project, open the terminal at the folder and run the below command

  git clone https://github.com/kesrishubham2510/blog-poc.git
  

Running the Applications

• Make sure you have Java version 17 or later

• After Successfull cloning, from the same path run,

  mvn clean; mvn compile
  

  to clean and build the jar files.

• Open the repository in vscode or any other IDE. While running the application make sure to use jakarta.persistence.Id and org.springframework.data.annotation.Id (in com.blog.library.Message) when running mvcapi and reactiveapi respectively.

Use Jmeter to test APIs