ERROR: In file './docker-compose.yml', volume must be a mapping not a string

docker-compose, docker-volume, wordpress

Solution

In my case this was happening because I missed adding a `:` after the volume name.

Instead of:

volumes:
    - mysqldata:

I had typed:

volumes:
    - mysqldata

`docker-compose up` gave me the same error as above.

Problem

Question: Why do I get this error? ERROR: In file './docker-compose.yml', volume 'mariavolume' must be a mapping not a string. My docker-compose file is almost identical to this one: https://docs.docker.com/compose/wordpress/ ``` version: '2' services: wordpress: image: wordpress:latest restart: always depends_on: - db ports: - 8080:80 environment: WORDPRESS_DB_PASSWORD: example WORDPRESS_DB_HOST: 3306 db: image: mariadb restart: always environment: MYSQL_ROOT_PASSWORD: example volumes: - maria_volume: /var/lib/mysql volumes: maria_volume: ~/mariadb ```

Original source