springboot-rsocket-webflux-aop

The goal of this project is to play with RSocket protocol. For it, we will implement three Spring Boot Java applications: movie-server, movie-client-shell and movie-client-ui. As storage, it's used the reactive NoSQL database MongoDB. All the streaming of movie events and the logging are handling by AOP (Aspect Oriented Programming).

Proof-of-Concepts & Articles

On ivangfr.github.io, I have compiled my Proof-of-Concepts (PoCs) and articles. You can easily search for the technology you are interested in by using the filter. Who knows, perhaps I have already implemented a PoC or written an article about what you are looking for.

Project Diagram

Applications

• movie-server

  Spring Boot Java Web application that exposes REST API endpoints or RSocket routes to manage movies. Movies data are stored in reactive MongoDB.

  movie-server has the following profiles:

  • default

    • start REST API on port 8080 and uses HTTP

  • rsocket-tcp

    • start REST API on port 8080 and uses HTTP
    • start RSocket on port 7000 and uses TCP

  • rsocket-websocket

    • start REST API on port 8080 and uses HTTP
    • start RSocket with mapping-path /rsocket and uses WebSocket

• movie-client-shell

  Spring Boot Shell Java application that has a couple of commands to interact with movie-server.

  The picture below show those commands

  

  It has the following profiles:

  • default

    • start shell with enabled commands to call movie-server REST API endpoints using HTTP

  • rsocket-tcp

    • start shell with enabled commands to call movie-server REST API endpoints using HTTP
    • start shell with enabled commands to call movie-server RSocket routes using TCP

  • rsocket-websocket

    • start shell with enabled commands to call movie-server REST API endpoints using HTTP
    • start shell with enabled commands to call movie-server RSocket routes using WebSocket

• movie-client-ui

  Spring Boot Java Web application that uses Thymeleaf and Websocket to show at real-time all the events generated when movies are added, deleted, liked and disliked.

  

  movie-client-ui has the following profiles:

  • default

    • start REST API on port 8081 and uses HTTP
    • does not connect to movie-server through RSocket; does not receive movie events;

  • rsocket-tcp

    • start REST API on port 8080 and uses HTTP
    • connects to movie-server through RSocketusing TCP; receives movie events;

  • rsocket-websocket

    • start REST API on port 8080 and uses HTTP
    • connects to movie-server through RSocketusing WebSocket; receives movie events;

Demo

The GIF below shows a user running some commands in movie-client-shell, terminal on the right. In the right-top terminal is running movie-server and in the right-bottom, movie-client-ui. On the background, there's a browser where movie events are displayed.

Prerequisites

• Java 17+
• Docker

Start Environment

Open a terminal and inside springboot-rsocket-webflux-aop root folder run

docker compose up -d

Running applications with Maven

• movie-server

  Open a new terminal and, inside springboot-rsocket-webflux-aop root folder, run one of the following profile's command

  Profile	Command
  rsocket-tcp	./mvnw clean spring-boot:run --projects movie-server -Dspring-boot.run.profiles=rsocket-tcp
  rsocket-websocket	./mvnw clean spring-boot:run --projects movie-server -Dspring-boot.run.profiles=rsocket-websocket
  default	./mvnw clean spring-boot:run --projects movie-server

• movie-client-shell

  Open a new terminal and, inside springboot-rsocket-webflux-aop root folder, run the following command to build the executable jar file

  ./mvnw clean package --projects movie-client-shell -DskipTests
  

  To start movie-client-shell, run the profile's command you picked to run movie-server

  Profile	Commands
  rsocket-tcp	export SPRING_PROFILES_ACTIVE=rsocket-tcp && ./movie-client-shell/target/movie-client-shell-1.0.0.jar
  rsocket-websocket	export SPRING_PROFILES_ACTIVE=rsocket-websocket && ./movie-client-shell/target/movie-client-shell-1.0.0.jar
  default	export SPRING_PROFILES_ACTIVE=default && ./movie-client-shell/target/movie-client-shell-1.0.0.jar

• movie-client-ui

  Open a new terminal and, inside springboot-rsocket-webflux-aop root folder, run the profile's command you picked to run movie-server

  Profile	Command
  rsocket-tcp	./mvnw clean spring-boot:run --projects movie-client-ui -Dspring-boot.run.profiles=rsocket-tcp
  rsocket-websocket	./mvnw clean spring-boot:run --projects movie-client-ui -Dspring-boot.run.profiles=rsocket-websocket
  default	./mvnw clean spring-boot:run --projects movie-client-ui

Running applications as Docker containers

• Build Docker images

  • In a terminal, make sure you are in springboot-rsocket-webflux-aop root folder
  • Run the following script to build the Docker images
    • JVM

      ./docker-build.sh
      

    • Native (it's not working yet, see Issues)

      ./docker-build.sh native
      

• Environment variables

  • movie-server

    Environment Variable	Description
    MONGODB_HOST	Specify host of the Mongo database to use (default localhost)
    MONGODB_PORT	Specify port of the Mongo database to use (default 27017)

  • movie-client-shell

    Environment Variable	Description
    MOVIE_SERVER_HOST	Specify host of the movie-server to use (default localhost)

  • movie-client-ui

    Environment Variable	Description
    MOVIE_SERVER_HOST	Specify host of the movie-server to use (default localhost)

• Start Docker containers

  • In a terminal, make sure you are inside springboot-rsocket-webflux-aop root folder
  • Run following command
    • rsocket-tcp

      ./start-server-and-ui.sh rsocket-tcp && ./start-shell.sh rsocket-tcp
      

    • rsocket-websocket

      ./start-server-and-ui.sh rsocket-websocket && ./start-shell.sh rsocket-websocket
      

    • default

      ./start-server-and-ui.sh && ./start-shell.sh
      

Application's URL

Application	Type	Transport	URL
movie-server	RSocket	TCP	tcp://localhost:7000
movie-server	RSocket	WebSocket	ws://localhost:8080/rsocket
movie-server	REST	HTTP	http://localhost:8080
movie-client-ui	Website	HTTP	http://localhost:8081

Note: you can see the clients connected to movie-server by calling the info actuator endpoint

curl -i localhost:8080/actuator/info

Playing Around with movie-client-shell commands

Note: to run the commands below, you must start movie-server and movie-client-shell with rsocket-tcp or rsocket-websocket profiles

• Open a browser and access movie-client-ui at http://localhost:8081

• Go to movie-client-shell terminal

• Add a movie using RSocket (Request-Response)

  add-movie-rsocket --imdb aaa --title "RSocketland"
  

  It should return

  {"imdb":"aaa","title":"RSocketland","lastModifiedDate":"2020-07-20T12:43:39.857248","likes":0,"dislikes":0}
  

  A + action should be displayed in movie-client-ui

• Add a movie using REST

  add-movie-rest --imdb bbb --title "I, REST"
  

  It should return

  {"imdb":"bbb","title":"I, REST","lastModifiedDate":"2020-07-20T12:44:13.266657","likes":0,"dislikes":0}
  

  A + action should be displayed in movie-client-ui

• Send a like to RSocketland movie using RSocket (Fire-And-Forget)

  like-movie-rsocket --imdb aaa
  

  It should return

  Like submitted
  

  A thumbs-up action should be displayed in movie-client-ui

• Get all movies using RSocket (Request-Stream)

  get-movies-rsocket
  

  It should return

  {"imdb":"aaa","title":"RSocketland","lastModifiedDate":"2020-07-20T12:56:34.565","likes":1,"dislikes":0}
  {"imdb":"bbb","title":"I, REST","lastModifiedDate":"2020-07-20T12:56:26.846","likes":0,"dislikes":0}
  

• Select movies using RSocket (Channel)

  select-movies-rsocket --imdbs aaa,bbb
  

  It should return

  | IMBD: aaa        | TITLE: RSocketland                    | LIKES: 1     | DISLIKES: 0     |
  | IMBD: bbb        | TITLE: I, REST                        | LIKES: 0     | DISLIKES: 0     |
  

• Delete movie RSocketland using RSocket (Request-Response) and movie I, REST using REST

  delete-movie-rsocket --imdb aaa
  delete-movie-rest --imdb bbb
  

  It should return, as response, the IMDB of the movies

  A - actions should be displayed in movie-client-ui

• Simulation

  There are two scripts that contain some commands to add, retrieve, like, dislikes and delete movies. One uses REST and another RSocket to communicate with movie-server. At the end of the script execution, it's shown the Execution Time in milliseconds.

  • If you are running the applications with Maven

    • REST

      script ../src/main/resources/simulation-rest.txt
      

    • RSocket

      script ../src/main/resources/simulation-rsocket.txt
      

  • If you are running the applications as Docker containers

    • REST

      script /app/resources/simulation-rest.txt
      

    • RSocket

      script /app/resources/simulation-rsocket.txt
      

Useful Commands

• MongoDB

  Find all movies

  docker exec -it mongodb mongosh moviedb
  db.movies.find()
  

  Type exit to get out of MongoDB shell

Shutdown

• To stop movie-client-shell, go to the terminal where it is running and type exit
• To stop movie-server and movie-client-ui
  • If you start them with Maven, go to the terminals where they are running and press Ctrl+C
  • If you start them as Docker containers, go to a terminal and, inside springboot-rsocket-webflux-aop root folder, run the following command

    ./stop-server-and-ui.sh
    

• To stop and remove docker compose mongodb container, network and volumes, go to a terminal and, inside springboot-rsocket-webflux-aop root folder, run the command below

  docker compose down -v
  

Cleanup

To remove the Docker images created by this project, go to a terminal and, inside springboot-rsocket-webflux-aop root folder, run the script below

./remove-docker-images.sh

References

• https://docs.spring.io/spring/docs/current/spring-framework-reference/web-reactive.html#rsocket
• https://spring.io/blog/2020/05/12/getting-started-with-rsocket-servers-calling-clients
• https://grapeup.com/blog/reactive-service-to-service-communication-with-rsocket-introduction/

Issues

movie-server

Docker native image builds and starts up successfully. However, it doesn't accept connections even using JVM version of movie-client-ui and movie-client-shell.

movie-client-ui

After building and starting the Docker native image successfully, the app looks fine (i.e., we can open the page, websocket is connected, etc). However, it is not connecting to movie-server.

movie-client-shell

After building the Docker native image and running it successfully, we have some problems such as

• there is the following WARN

  Unable to create a system terminal, creating a dumb terminal (enable debug logging for more information)
  

• the autocomplete is not working;
• when tried to run one of script files (simulation-rest.txt or simulation-rsocket.txt) there is the following exception

  movie-client-shell> script /app/resources/simulation-rest.txt
  java.lang.NullPointerException
  Details of the error have been omitted. You can use the stacktrace command to print the full stacktrace.
  movie-client-shell> stacktrace
  java.lang.NullPointerException
  	at java.base@17.0.7/java.io.FileInputStream.<init>(FileInputStream.java:149)
  	at java.base@17.0.7/java.io.FileReader.<init>(FileReader.java:75)
  	at org.springframework.shell.standard.commands.Script.script(Script.java:60)
  	at java.base@17.0.7/java.lang.reflect.Method.invoke(Method.java:568)
  	at org.springframework.shell.command.invocation.InvocableShellMethod.doInvoke(InvocableShellMethod.java:306)
  	at org.springframework.shell.command.invocation.InvocableShellMethod.invoke(InvocableShellMethod.java:232)
  	at org.springframework.shell.command.CommandExecution$DefaultCommandExecution.evaluate(CommandExecution.java:227)
  	at org.springframework.shell.Shell.evaluate(Shell.java:248)
  	at org.springframework.shell.Shell.run(Shell.java:159)
  	at org.springframework.shell.jline.InteractiveShellRunner.run(InteractiveShellRunner.java:73)
  	at org.springframework.shell.DefaultShellApplicationRunner.run(DefaultShellApplicationRunner.java:65)
  	at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:762)
  	at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:752)
  	at org.springframework.boot.SpringApplication.run(SpringApplication.java:319)
  	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1306)
  	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1295)
  	at com.ivanfranchin.movieclientshell.MovieClientShellApplication.main(MovieClientShellApplication.java:10)