Why is Docker ignoring my container_name stipulation?-CodePudding

I'm running a Docker compose file main services with three dependent, sub-services as follows:

docker-compose run -p hlp-api --service-ports web

This spins everything up nicely. However, while the sub-services end up with the name I intended, the main service has a name based on the project token (hlp-api) I fed in plus an ugly auto-generated appendage.

Why is the main 'web' service not ending up with the name I specify in its container_name param?

docker-compose.yml:

version: '2'

services:

  # web service
  web:
    container_name: hlp-api-web
    build:
        context: .
        dockerfile: Dockerfile
    command: /bin/sh -c "gem install bundler && bundle install && rails server --port 3000 --binding 0.0.0.0"
    ports:
      - 3000:3000
      - 5432:5432
      - 2222:2222
    volumes:
      - ./webapp:/opt/webapp
      - ../:/app:cached
      - bundle:/usr/local/bundle
      - rails_cache:/app/tmp/cache
      - node_modules:/app/node_modules
    depends_on:
      - postgres
      - ngrok

  # database
  postgres:
    container_name: hlp-api-db
    image: postgres:14.2
    volumes:
      - .psqlrc:/root/.psqlrc:ro
      - dbdat:/var/lib/postgresql/data
      - ./log:/root/log:cached
      - ./latest.dump:/latest.dump
    environment:
      POSTGRES_DB: hlp-api-dev
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres
      DB_PORT: 5432
    ports:
      - 5432
    healthcheck:
      test: pg_isready -U postgres -h 127.0.0.1
      interval: 5s

  # ngrok
  ngrok:
    container_name: hlp-api-ngrok
    image: ngrok/ngrok:latest
    environment:
      - NGROK_AUTHTOKEN
    command: http host.docker.internal:3000

volumes:
  web:
  bundle:
  dbdat:
  node_modules:
  rails_cache:

CodePudding user response：

I would guess, for the same reason you have to explicitly use --service-ports, they decided that they didn't want name collisions as they didn't wanted to have ports collisions.

If the name would be respected from the docker compose run command, that would means that you would always have to specify a name when you want to run the command, if the container is already running, as it will keep on trying to assign the same name over and over again.

The good thing is that you can provide a name, as you can ask it to respect the published ports:

docker-compose run -p hlp-api --service-ports --name hlp-api-web web

https://github.com/docker/compose/issues/2061, and more specifically: this comment

CodePudding user response：

docker-compose run is intended to spin up a one-off container to run a temporary command. It will start the services the named container depends_on:. It doesn't actually launch the specific container described in the docker-compose.yml, but a related container with a different name and a different command.

If you want to actually start the containers listed in the docker-compose.yml file, use docker-compose up.

A typical use of docker-compose run would be to invoke database migrations, for example:

# Start the entire system
docker-compose up -d

# Start a new temporary container, with the same image and setup
# as the normal Rails container, to run migrations
docker-compose run web \
  bundle exec rails db:migrate