Debug a service defined in docker-compose.yml

Question

I'm trying to enable remote debugging for one of the services included in my integration test. Most of the tests work fine, however if a test fails it is difficult to debug one of the other services. The (simplified) structure of the integration test is as follows:

Service A (service under test) -> GraphQL service -> Stubbed REST services

I'm using the following setup:

Service A docker-compose.yml

version: '3.5'

services:
  rest-stubs:
    image: rest-stubs:1.2.3
    container_name: rest-stubs
    ports:
      - "8082:8080"

  graphql-service:
    image: graphql-service:1.2.3
    container_name: graphql-service
    ports:
      - "8083:8080"
      - "5005:5005"
    environment:
      - some.stub-url=http://rest-stubs:8080/some-stub-url

Dockerfile of graphql-service:

FROM graphql-service

EXPOSE 8080 8080
EXPOSE 5005 5005

ADD app/target/service-*-exec.jar /app/spring-boot-service.jar

CMD ["-java -agentlib:jdwp=transport=dt_socket,address=*:5005,server=y,suspend=n \
            -jar /app/spring-boot-service.jar"]

When I perform the integration test located in service A, the services defined in the docker-compose.yml spin up. I would have expected to be able to connect to the graphQL service' remote debugging port on 5005, however I receive a Unable to open debugger port (localhost:5005): java.net.ConnectException "Connection refused (Connection refused) exception.

Does anyone know how I can properly remote debug a docker service?

Answer 1

EXPOSE will only expose to others containers that are linked, such as other services in the network without publishing the port to the host machine .

You need to be publish it like this:

version: '3.5'

services:
  rest-stubs:
    image: rest-stubs:1.2.3
    container_name: rest-stubs
    ports:
      - "8082:8080"

  graphql-service:
    image: graphql-service:1.2.3
    container_name: graphql-service
    ports:
      - "8083:8080"
      - "5005:5005"
    environment:
      - some.stub-url=http://rest-stubs:8080/some-stub-url

Answer 2

Found the answer; I tried to connect to the container by using localhost:5005 settings in the IntelliJ remote debugger instead of the container's IP address.

I have obtained the IP address of the container using the answer in this post and used that IP address in Intellij's remote debugger dialog to connect instead.