RabbitMq Spring Boot deploy docker

Question

I've got a spring boot application with producer and receiver which uses the local rabbitmq to send and receive messages. I am trying to deploy both the app and rabbit on docker container and once deployed run the boot app. Once the app is started it has a producer which implements Spring CommandLineRunner meaning that the app immediately starts sending messages so there must be a rabbitmq broker running prior. I am very new to docker. I tried so far:

1). I created image for the spring boot app as the following

FROM java:8
EXPOSE 8080
ADD /target/MessagingApp.jar MessagingApp.jar
ENTRYPOINT ["java","-jar","MessagingApp.jar"]

2). Then created docker.compose file for rabbit and my newly created image

rabbitmq:
  image: rabbitmq:management
  ports:
    - "5672:5672"
    - "15672:15672"
messagingapp:
  image: messagingapp:latest
  ports:
    - "80:8080"
  links:
    - rabbitmq

I then ran docker-compose up and I can see rabbit started to some extend and then spring boot app but fails sending messages with

at com.rabbitmq.client.impl.SocketFrameHandlerFactory.create..

I think my issue is that my spring boot app automatically tries to connect to the localhost rabbit host. So how do I make it point to the docker rabbitmq server?

Any help?

Answer 1

Try update part of links for depends_on . Your application probably start before messagingapp .

Part of documentation for depends_on

docker-compose up will start services in dependency order. When docker-compose execute V2 files, it will automatically build a network between all of the containers defined in the file, and every container will be immediately able to refer to the others just using the names defined in the docker-compose.yml file.

But

Note: depends_on will not wait for db and redis to be “ready” before starting web - only until they have been started.

For that check Controlling startup order .

You need add command for checking state of service. More in documentation...

depends_on:
      - "db"
    command: ["./wait-for-it.sh", "db:5432", "--", "python", "app.py"]

Answer 2

Your Dockerfile and docker-compose.yml files seem correct except for two things:

1. instead of the keyword links , you need to use depends_on . This will build and run RabbitMQ instance first, then your web service.

2. you should add this line under your messagingapp service:

-->

environment:
-  SPRING_RABBITMQ_HOST=rabbitmq

This will let your Spring Boot application to recognize the RabbitMQ image in Docker.

So, try to update your docker-compose.yml file like this:

rabbitmq:
  image: rabbitmq:management
  ports:
    - "5672:5672"
    - "15672:15672"
messagingapp:
  image: messagingapp:latest
  ports:
    - "80:8080"
  environment:
    - SPRING_RABBITMQ_HOST=rabbitmq
  depends_on:
    - rabbitmq