"volumes 'type' is a required property" when running docker-compose

Question

I am working through understanding how docker-compose.yaml works. I am trying to define a volume inside the compose file and to mount it at a mount point locally. I try to run a basic .yaml to mount my volume:

version: '3.2'
services:
      mydb:
        image: postgres
        volumes:
          - db-data:var/lib/postgres/data
        ports:
          - "5432:5432"
        volumes:
          - db-data:
          - driver: local

But when I run docker-compose down , I get an error:

$ docker-compose down
The Compose file '.\docker-compose.yml' is invalid because:
services.mydb.volumes 'type' is a required property
services.mydb.volumes 'type' is a required property

I am new to this and still am understanding all the nuances of working with Docker. I think that my problem is that it's an either an indention error or how I am calling the version number with the extension, but I can't seem to understand the error.

BMitch · Accepted Answer · 2019-01-04T18:39:37.627

The compose file is whitespace sensitive (this is yaml formatting). There are two different volume sections in a compose file, one where the volume is defined at the top level of indentation, and another where the volume is used within a service. You've attempted to define both within the service, and the second set of volumes is defined incorrectly for defining how to use the volume (it needs a target directory there). The following is what you want to try:

version: '3.2'
services:
      mydb:
        image: postgres
        volumes:
          - db-data:var/lib/postgres/data
        ports:
          - "5432:5432"
volumes:
  db-data:

"volumes 'type' is a required property" when running docker-compose

1 Answers1