Merge pull request #1362 from minrk/truncate_history_log

Don't log complete contents of history replies, even in debug

This changes the debug message to include only the length of the history reply, rather than its entire contents, which gets huge, and is an impediment to the legibility of debugging output.

IPython/frontend/qt/console/ipython_widget.py

@@ -179,7 +179,6 b' class IPythonWidget(FrontendWidget):'
         """ Implemented to handle history tail replies, which are only supported
             by the IPython kernel.
         """
-        self.log.debug("history: %s", msg.get('content', ''))
         content = msg['content']
         if 'history' not in content:
             self.log.error("History request failed: %r"%content)
@@ -199,6 +198,7 b' class IPythonWidget(FrontendWidget):'
         # reset retry flag
         self._retrying_history_request = False
         history_items = content['history']
+        self.log.debug("Received history reply with %i entries", len(history_items))
         items = []
         last_cell = u""
         for _, _, cell in history_items:

IPython/zmq/ipkernel.py

@@ -391,11 +391,12 b' class Kernel(Configurable):'
 
         else:
             hist = []
-        content = {'history' : list(hist)}
+        hist = list(hist)
+        content = {'history' : hist}
         content = json_clean(content)
         msg = self.session.send(self.shell_socket, 'history_reply',
                                 content, parent, ident)
-        self.log.debug(str(msg))
+        self.log.debug("Sending history reply with %i entries", len(hist))
 
     def connect_request(self, ident, parent):
         if self._recorded_ports is not None: