Fix reauthorization to work beyond the first time called

AUTHORS.md

@@ -15,7 +15,8 @@ The following wonderful people contributed directly or indirectly to this projec
 - Josh Mandel <https://github.com/jmandel>
 - Nikolai Schwertner <https://github.com/nschwertner>
 - Pascal Pfiffner <https://github.com/p2>
-- Raheel Sayeed <https://github.com/raheelsayeed> 
+- Raheel Sayeed <https://github.com/raheelsayeed>
+- Tim Harsch <https://github.com/timharsch>
 - Trinadh Baranika <https://github.com/bktrinadh>
 
 Please add yourself here alphabetically when you submit your first pull request.

fhirclient/auth.py

@@ -294,11 +294,11 @@ def _request_access_token(self, server, params):
         # The refresh token issued by the authorization server. If present, the
         # app should discard any previous refresh_token associated with this
         # launch, replacing it with this new value.
-        refresh_token = ret_params.get('refresh_token')
+        refresh_token = ret_params.get('refresh_token') or params.get('refresh_token')
         if refresh_token is not None:
             self.refresh_token = refresh_token
-            del ret_params['refresh_token']
-
+            if 'refresh_token' in ret_params:
+                del ret_params['refresh_token']
         logger.debug("SMART AUTH: Received access token: {0}, refresh token: {1}"
             .format(self.access_token is not None, self.refresh_token is not None))
         return ret_params