title: NodeJS Google Vision is unable to detect a Project Id in the current environment
body: <p>Under Ubuntu environment, NodeJS Google Vision complains:</p>
  
  <blockquote>
    <p><strong>Error</strong>: Unable to detect a Project Id in the current environment.</p>
  </blockquote>
  
  <p>Even though I already put json credential through</p>
  
  <pre><code>$ export GOOGLE_APPLICATION_CREDENTIALS=/var/credential_google.json"
  </code></pre>
  
  <p>Please help.</p>