hadasbro/realtime-notifer

Realtime notifications, realtime publisher [ Java, Spring Boot, Hibernate, Flyway, Jackson, Thymeleaf, SockJS, Stomp, MySQL, RethinkDB ]

Realtime notifications, realtime publisher

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Overview

This is just an example project how can we publish and subscribe realtime notification to user and/or concrete sessions.

Solution base on Spring + websocked + RethinkDB

Inside:

• Spring Boot (https://spring.io/projects/spring-boot)

• Hibernate (http://hibernate.org/)

• SockJs (https://github.com/sockjs)

• Stomp (http://stomp.github.io/)

• Jackson (https://github.com/FasterXML/jackson-databind)

• Thymeleaf (https://www.thymeleaf.org/)

• MySql (https://www.mysql.com/)

• Rethink DB (https://www.rethinkdb.com/) [ alternatively you can use Kafka (https://kafka.apache.org/)]

• Flyway (https://flywaydb.org/)

Communication flow

System has 2 layers. REST layer (Spring REST + MySQL) and the Socket Communication Layer to communicate with client and subscribe changes in RethinkDB.

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Testing on Docker

1. Build app image

    realtime_notifer> mvn clean package docker:build
   

2. Go to /docker directory

    realtime_notifer> cd ./src/main/docker
   

3. Docker compose

    realtime_notifer/src/main/docker> docker-compose up
   

4. Check out client and sender HTML/JS example

   • http://HOST/client
   • http://HOST/sender

   HOST = localhost:8090 or just container's host e.g. http://192.168.99.100:8090

5. Useful docker commands

    : go to cantainer and run bach
    docker exec -it realtime_notifer /bin/bash
    
    : stop all containers
    docker stop $(docker ps -a -q)
    
    : delete all containers
    docker rm $(docker ps -a -q)
    
    : delete all images 
    docker rmi $(docker images -q)
    
    : restart docker machine
    docker-machine restart default
    
    : get the IP address of machines
    docker-machine ip
   

Test example:

Run without Docker

1. Update application.properties and set up your MySQL and RethinkDB credentials.

2. If you need some example data you can run Flyway Migration

    mvn flyway:migrate -Dflyway.configFile=src/main/resources/application.properties
   

3. Open a few clients and sender

4. Try to send any notification to any client

See more

Apache Kafka example: https://www.baeldung.com/spring-kafka

Web sockets: https://docs.spring.io/spring/docs/current/spring-framework-reference/web.html#websocket

Flyway migrations: https://flywaydb.org/

Docker: https://www.docker.com/

Authors

• Slawomir Hadas - author - Github