title: docker compose command: Invalid interpolation format for "command" option in service
body: <p>In my docker compose I have the following command:</p>
  
  <pre><code>command: bash -c 'while [[ "$(curl --connect-timeout 2 -s -o /dev/null -w ''%{http_code}'' https://mock-server:4000/readiness)" != "200" ]]; do echo ..; sleep 5; done; echo backend is up; npm start'
  </code></pre>
  
  <p>which waits until mock-server is up then run the start command for backend:</p>
  
  <pre><code>  backend:
      build: 
          context: ./test
          dockerfile: Dockerfile
      command: bash -c 'while [[ "$(curl --connect-timeout 2 -s -o /dev/null -w ''%{http_code}'' https://mock-server:4000/readiness)" != "200" ]]; do echo ..; sleep 5; done; echo backend is up; npm start'
      ports: 
        - "3015:3015"
      depends_on:
        - couchdb
        - redis
        - mock-server
      user: root
  </code></pre>
  
  <p>But I get the following error:</p>
  
  <pre><code>ERROR: Invalid interpolation format for "command" option in service "backend": "bash -c 'while [[ "$(curl --connect-timeout 2 -s -o /dev/null -w ''%{http_code}'' https://uds-mock-server:4000/readiness)" != "200" ]]; do echo ..; sleep 5; done; echo backend is up;; npm start'"
  </code></pre>
  
  <p>I cannot see what is wrong with my command.
  any help is appreciated</p>