title: How connect tot Google Cloud SQL via Exposed
body: <p>I develop app on GAE using Kotlin, Ktor. Database is CloudSQL. For connect to it use Exposed library</p>
  
  <pre><code>Database.connect(
              "jdbc:postgresql://cloudsql/&lt;project-id&gt;:&lt;zone-name&gt;:&lt;instance-name&gt;",
              driver="org.postgresql.Driver",
              user="postgres",
              password="********"
          )
  </code></pre>
  
  <p>But I get error:</p>
  
  <blockquote>
    <p>org.postgresql.core.v3.ConnectionFactoryImpl log: IOException occurred while connecting to cloudsql:5432 (ConnectionFactoryImpl.java:317)
    java.net.UnknownHostException: cloudsql</p>
    
    <p>.......</p>
  </blockquote>
  
  <p>I try change url on:</p>
  
  <pre><code>    jdbc:postgresql://google/&lt;project-id&gt;:&lt;zone-name&gt;:&lt;instance-name&gt;
      jdbc:postgresql://cloudsql/&lt;project-id&gt;:&lt;zone-name&gt;:&lt;instance-name&gt;/.s.PGSQL.5432
  
  </code></pre>
  
  <p>But also can this error.</p>
  
  <p>Error is geted both on local and server</p>