title: Return a Promise from Redux Observable
body: <p>Maybe I'm thinking about this wrong, but a common pattern I use with redux-thunk is to return a promise so I can perform some additional actions in the container object when something completes or fails. </p>
  
  <hr>
  
  <p>Using Thunk as an example:</p>
  
  <p>Action Creator:</p>
  
  <pre><code>const action = ({ data }) =&gt; (dispatch) =&gt; 
      fetch(`some http url`)
      .then(response =&gt; {
          if(response.ok) {
               return response.json();
          }
  
          return Promise.reject(response);
      })
  </code></pre>
  
  <p>Somewhere in the connected component:</p>
  
  <pre><code>this.props.action("Some Data")
      .then(console.log)
      .catch(error =&gt; console.error("ERROR"));
  </code></pre>
  
  <hr>
  
  <p>Is there a clean way of doing something similar in Redux-Observable/Rxjs? Basically returning a promise from an action, calling an epic, that returns resolve or reject once the observable is complete.</p>