title: AWS API gateway as subscriber to Google Cloud pubsub
body: <p>I want to subscribe to a Google Cloud pub-sub topic (which will push notifications about user's inbox changes). Since Google requires a HTTPS endpoint I created an AWS API Gateway endpoint. But I'm unable to add this endpoint as a subscriber. </p>
  
  <p>I get an error saying - <strong>"Sorry, there’s a problem. If you entered information, check it and try again. Otherwise, the problem might clear up on its own, so check back later."</strong>. </p>
  
  <p>Any ideas why this is happening and how I can fix this?</p>
  
  <p>Azeem</p>