title: Docker-compose build blocked after saying "Building <service>"
body: <p>I needed to rebuild a container and since then nothing works as expected:</p>
  
  <pre><code>docker-compose build 
  Building web
  </code></pre>
  
  <p>The whole thing remains blocked there, while the same config will work locally. Here's what I have:</p>
  
  <pre><code>docker-compose version 1.11.0, build 6de1806
  docker-py version: 2.0.2
  CPython version: 2.7.13
  OpenSSL version: OpenSSL 1.0.1t  3 May 2016
  
  Client:
   Version:      17.05.0-ce
   API version:  1.29
   Go version:   go1.7.5
   Git commit:   89658be
   Built:        Thu May  4 22:10:54 2017
   OS/Arch:      linux/amd64
  
  Server:
   Version:      17.05.0-ce
   API version:  1.29 (minimum version 1.12)
   Go version:   go1.7.5
   Git commit:   89658be
   Built:        Thu May  4 22:10:54 2017
   OS/Arch:      linux/amd64
   Experimental: false
  </code></pre>
  
  <p>On <code>Ubuntu 16.04</code>.</p>
  
  <p>And the <code>docker-compose.yml</code>:</p>
  
  <pre><code>web:
    build: .
    command: npm start
    volumes:
      - .:/app
      - /app/node_modules
    ports:
      - "3030:3030"
  </code></pre>
  
  <p>What can the mistake be? I'm sure it is a small tiny detail...
  Or how can I debug this?</p>
  
  <p>I tried to uninstall/reinstall everything, even removed <code>/var/lib/docker</code> content...</p>
  
  <hr>
  
  <p>EDIT:</p>
  
  <p>If I run the command with the <code>--verbose</code> flag, I get:</p>
  
  <pre><code>compose.config.config.find: Using configuration files: ./docker-compose.yml
  docker.auth.find_config_file: Trying paths: ['/root/.docker/config.json', '/root/.dockercfg']
  docker.auth.find_config_file: No config file found
  compose.cli.command.get_client: docker-compose version 1.11.0, build 6de1806
  docker-py version: 2.0.2
  CPython version: 2.7.13
  OpenSSL version: OpenSSL 1.0.1t  3 May 2016
  compose.cli.command.get_client: Docker base_url: http+docker://localunixsocket
  compose.cli.command.get_client: Docker version: KernelVersion=4.4.0-75-generic, Arch=amd64, BuildTime=2017-05-04T22:10:54.638119411+00:00, ApiVersion=1.29, Version=17.05.0-ce, MinAPIVersion=1.12, GitCommit=89658be, Os=linux, GoVersion=go1.7.5
  compose.service.build: Building web
  compose.cli.verbose_proxy.proxy_callable: docker build &lt;- (pull=False, stream=True, nocache=False, tag=u'api_web', buildargs=None, rm=True, forcerm=False, path='/var/www/api', dockerfile=None)
  </code></pre>
  
  <p>And if I try to build without compose, it works:</p>
  
  <pre><code>docker build .
  </code></pre>