title: SNS + CloudFormation
body: <p>I'm using <em>AWS CloudFormation</em> to build a stack for a microservice. My <em>AWS CloudFormation</em> template creates resources like: a Lambda function, an SNS topic and API Gateway.</p>
  
  <p>This microservice does some work and publishes messages to the SNS topic. Other microservices subscribe to this topic.</p>
  
  <p>The problem I'm facing is that when I upgrade my microservice's <em>CloudFormation</em> template (sometimes I need to redeploy it, and recreate all resources), the SNS topic changes its <code>ARN</code>. Hence, all microservices that use this topic need to change as well.</p>
  
  <p>I think I could create a separate <em>CloudFormation</em> template for the SNS topic (I have more than one per microservice).</p>
  
  <ul>
  <li>Will this be a good approach? </li>
  <li>If not, what's the recommended way?</li>
  </ul>