Consume artifacts from child pipelines

I am using parent/child pipelines in a single project and attempting to pass artifacts between child pipelines. The documentation says this is possible, but doesn’t state how to do it.

My parent pipeline is called “Base” and it kicks off two child pipelines in successive stages:

  1. Node - builds a nodejs application and artifacts “node_modules” directory
  2. Docker - builds a docker image, copying in the “node_modules” artifact generated from the Node pipeline

I think all I have to do is somehow get the $CI_PIPELINE_ID from the Node pipeline up into the parent, then pass that pipeline into the Docker pipeline so it can access the artifacts:

Build Docker:
  stage: Build
  needs:
    - pipeline: $NODE_PIPELINE_ID
      job: Build Node

Any ideas? I’d prefer not to have the Node pipeline trigger the docker one, but I can do that if I need to, it will just be less straight forward for developers to view the pipeline results in the web UI.