refactor: handle StopIteration separately in exception chain

Author: eiri

ibmcloudant/features/changes_follower.py

@@ -181,9 +181,13 @@ def _request_callback(self):
                 if self._stop.is_set():
                     raise StopIteration
                 self._buffer.put(results)
+            except StopIteration as e:
+                self.logger.debug('Iterator stopped.')
+                self._buffer.join()
+                self._buffer.put(e)
+                break
             except Exception as e:
-                if type(e) is not StopIteration:
-                    self.logger.debug(f'Exception getting changes {e}')
+                self.logger.debug(f'Exception getting changes {e}')
                 if (
                     self._transient_suppression == _TransientErrorSuppression.NEVER
                     or (
@@ -197,14 +201,8 @@ def _request_callback(self):
                     self._buffer.join()
                     self._buffer.put(e)
                     break
-                if (
-                    type(e) is ApiException and e.status_code in [400, 401, 403, 404]
-                    or type(e) is StopIteration
-                ):
-                    if type(e) is StopIteration:
-                        self.logger.debug('Iterator stopped.')
-                    else:
-                        self.logger.debug('Terminal error.')
+                if type(e) is ApiException and e.status_code in [400, 401, 403, 404]:
+                    self.logger.debug('Terminal error.')
                     self._buffer.join()
                     self._buffer.put(e)
                     break