title: What is the Docker image for the Cloud SQL proxy and why is it used?
body: <p>I'm following <a href="https://cloud.google.com/python/django/kubernetes-engine" rel="nofollow noreferrer">the tutorial on how to deploy a Django application to the Kubernetes Engine</a> in the Google Cloud Platform and on step 9 it does this:</p>
  
  <blockquote>
    <ol start="9">
    <li><p>Retrieve the public Docker image for the Cloud SQL proxy.</p>
  
  <pre><code>docker pull b.gcr.io/cloudsql-docker/gce-proxy:1.05
  </code></pre></li>
    </ol>
  </blockquote>
  
  <p>What is this Cloud SQL proxy image? Am I understand it correctly that the application, the web workers, are deployed to images built on top of the Cloud SQL proxy image? Is this so that they can access the database?</p>
  
  <p>Looking at <a href="https://github.com/GoogleCloudPlatform/python-docs-samples/blob/master/container_engine/django_tutorial/polls.yaml" rel="nofollow noreferrer">the yaml file</a> for the application, it looks like the image generated out of the Cloud SQL proxy will be running the application bu then there's another container that is just the cloudsql-docker image. Why is this second container needed?</p>