title: Cloud Firestore security rules - single protected field in a document
body: <p>I'd like to have a read-only property called <code>suspendedProfile</code> in a <code>user</code> document with all the other properties with read/write access for currently logged in user. Is there a way to do it with a simple security rule? </p>
  
  <p>I thought about 2 solutions: </p>
  
  <ol>
  <li>disallow writes that modify the property like <code>allow write: if request.resource.data.suspendedProfile == null;</code></li>
  <li>a <code>/secure</code> collection with <code>allow read;</code> inside the <code>user</code> document </li>
  </ol>
  
  <p>I think the first option is better all the user-related properties are in a single docment, but I'd love to hear your thoughts. Is there any other simpler way to achieve this?</p>