title: REST: Get query only changeable objects
body: <p>I'm having a bunch of apis which return several types of data.
  All users can query all data by using a GET rest api.</p>
  
  <p>A few users can also change data. What is a common approach when designing REST API, to query only the data that can be changed by the current user but still allow the api to return all data (for display mode).</p>
  
  <p>To explain it further:</p>
  
  <p>The software manages projects. All projects are accessible for all users (also anonymous) via an api (let's call it GET api/projects).
  A user has the ability to see a list of all projects he is involved in and which he can edit. 
  The api should return exactly the same data but limited to the projects he is involed in.</p>
  
  <p>Should I create an additonal parameter, or maybe pass an http header, or what else?</p>