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ruby-on-railsrubydockerdocker-composesidekiq

Does Sidekiq running multiple times when we replicate the Ruby on Rails container?

I have a Ruby on Rails container with Sidekiq in it.

I have a schedule/cron job in the application. As We know, schedule jobs are registered when the application boots.

If I assume that there will be many users one day and I will create multiple container instances for the application, will this cause Sidekiq to execute on multiple containers?

If the answer is yes (execute multiple jobs in each container), how do I make this job only executed by one container?

version: '3.8'
services:

  thedatabase:
    image: postgres:12
    volumes:
      - ./database:/var/lib/postgresql/data
    environment:
      POSTGRES_USER: theuser
      POSTGRES_PASSWORD: thepass
    ports: 
      - '5432:5432'
    networks: 
      - excnetwork

  theapi:
    build: 
      context: ./dex-api
      dockerfile: Dockerfile
    volumes:
      - ./dex-api:/web
    env_file: 
      - ./dex-api/.env
    ports:
      - "8081:3000"
    depends_on:
      - thedatabase
    networks: 
      - excnetwork

  redis:
    image: redis
    command: 'redis-server --requirepass "yourpassword"'
    volumes:
      - ./redis:/var/lib/redis/data
    ports:
      - '6379:6379'
    networks: 
      - excnetwork

volumes:
  database:
  dex-api:
  redis:
  
networks: 
  excnetwork:
    driver: bridge
Solution

  • Whilst there's no single answer that solves it all you can use tried and tested means. One of them is to put Sidekiq in a sidecar. You definitely need Sidekiq to be run as a single, independent instance.

    There are other patterns for a multi-container solution such as ambassador and adapter but, a sidecar seems to be the most appropriate option in this instance.

    Read more here: