Replicate 'docker volume create --name data' command on docker-compose.yml

Question

I'm building my containers with docker-compose and I would like to use the new volume API from Docker, but I don't see how to.

I want to be able to say docker-compose up -d to:

• Create a volume, or use it if already created.
• Create services containers with data from previous volume container.

Answer 1

First of all you must be using a version 2 Compose file to use the new specifications for creating and using named volumes. The Compose File Reference includes all you need to know, including examples.

To summarize:

1. Add version: '2' to the top of docker-compose.yml.
2. Place service units under a services: key.
3. Place volume units under a volumes: key.
4. When referring to a named volume from a service unit, specify volumename:/path where volumename is the name given under the volumes: key (in the example below it is dbdata) and /path is the location inside the container of the mounted volume (e.g., /var/lib/mysql).

Here's a minimal example that creates a named volume dbdata and references it from the db service.

version: '2'
services:
  db:
    image: mysql
    volumes:
      - dbdata:/var/lib/mysql
volumes:
  dbdata:
    driver: local