Merge branch 'keepkernel' of https://github.com/minrk/ipython into mi…

…nrk-keepkernel

Closes pull request gh-164.

IPython/frontend/qt/console/frontend_widget.py

@@ -3,6 +3,7 @@
 # Standard library imports
 from collections import namedtuple
 import sys
+import time
 
 # System library imports
 from pygments.lexers import PythonLexer
@@ -361,6 +362,19 @@ def _handle_stream(self, msg):
             self._append_plain_text(text)
             self._control.moveCursor(QtGui.QTextCursor.End)
 
+    def _handle_shutdown_reply(self, msg):
+        """ Handle shutdown signal, only if from other console.
+        """
+        if not self._hidden and not self._is_from_this_session(msg):
+            if not msg['content']['restart']:
+                sys.exit(0)
+            else:
+                # we just got notified of a restart!
+                time.sleep(0.25) # wait 1/4 sec to reset
+                                 # lest the request for a new prompt
+                                 # goes to the old kernel
+                self.reset()
+
     def _started_channels(self):
         """ Called when the KernelManager channels have started listening or 
             when the frontend is assigned an already listening KernelManager.

IPython/frontend/qt/console/ipythonqt.py

@@ -31,11 +31,18 @@ class MainWindow(QtGui.QMainWindow):
     # 'object' interface
     #---------------------------------------------------------------------------
     
-    def __init__(self, frontend):
+    def __init__(self, app, frontend, existing=False):
         """ Create a MainWindow for the specified FrontendWidget.
+        
+        The app is passed as an argument to allow for different
+        closing behavior depending on whether we are the Kernel's parent.
+        
+        If existing is True, then this Window does not own the Kernel.
         """
         super(MainWindow, self).__init__()
+        self._app = app
         self._frontend = frontend
+        self._existing = existing
         self._frontend.exit_requested.connect(self.close)
         self.setCentralWidget(frontend)
     
@@ -50,11 +57,18 @@ def closeEvent(self, event):
         if kernel_manager and kernel_manager.channels_running:
             title = self.window().windowTitle()
             reply = QtGui.QMessageBox.question(self, title,
-                'Close console?', QtGui.QMessageBox.Yes, QtGui.QMessageBox.No)
-            if reply == QtGui.QMessageBox.Yes:
+                "Close just this console, or shutdown the kernel and close "+
+                "all windows attached to it?", 
+                'Cancel', 'Close Console', 'Close All')
+            if reply == 2: # close All
                 kernel_manager.shutdown_kernel()
                 #kernel_manager.stop_channels()
                 event.accept()
+            elif reply == 1: # close Console
+                if not self._existing:
+                    # I have the kernel: don't quit, just close the window
+                    self._app.setQuitOnLastWindowClosed(False)
+                event.accept()
             else:
                 event.ignore()
 
@@ -132,7 +146,7 @@ def main():
     widget.kernel_manager = kernel_manager
 
     # Create the main window.
-    window = MainWindow(widget)
+    window = MainWindow(app, widget, args.existing)
     window.setWindowTitle('Python' if args.pure else 'IPython')
     window.show()
 

IPython/frontend/qt/kernelmanager.py

@@ -105,6 +105,9 @@ class QtSubSocketChannel(SocketChannelQObject, SubSocketChannel):
     # last-resort sys.excepthook.
     crash_received = QtCore.pyqtSignal(object)
 
+    # Emitted when a shutdown is noticed.
+    shutdown_reply_received = QtCore.pyqtSignal(object)
+
     #---------------------------------------------------------------------------
     # 'SubSocketChannel' interface
     #---------------------------------------------------------------------------

IPython/zmq/ipkernel.py

@@ -330,7 +330,7 @@ def connect_request(self, ident, parent):
 
     def shutdown_request(self, ident, parent):
         self.shell.exit_now = True
-        self._shutdown_message = self.session.msg(u'shutdown_reply', {}, parent)
+        self._shutdown_message = self.session.msg(u'shutdown_reply', parent['content'], parent)
         sys.exit(0)
 
     #---------------------------------------------------------------------------
@@ -428,6 +428,7 @@ def _at_shutdown(self):
         # io.rprint("Kernel at_shutdown") # dbg
         if self._shutdown_message is not None:
             self.reply_socket.send_json(self._shutdown_message)
+            self.pub_socket.send_json(self._shutdown_message)
             io.raw_print(self._shutdown_message)
             # A very short sleep to give zmq time to flush its message buffers
             # before Python truly shuts down.

IPython/zmq/kernelmanager.py

@@ -305,7 +305,7 @@ def history(self, index=None, raw=False, output=True):
         self._queue_request(msg)
         return msg['header']['msg_id']
 
-    def shutdown(self):
+    def shutdown(self, restart=False):
         """Request an immediate kernel shutdown.
 
         Upon receipt of the (empty) reply, client code can safely assume that
@@ -318,7 +318,7 @@ def shutdown(self):
         """
         # Send quit message to kernel. Once we implement kernel-side setattr,
         # this should probably be done that way, but for now this will do.
-        msg = self.session.msg('shutdown_request', {})
+        msg = self.session.msg('shutdown_request', {'restart':restart})
         self._queue_request(msg)
         return msg['header']['msg_id']
 
@@ -743,7 +743,7 @@ def start_kernel(self, **kw):
         self.rep_address = (LOCALHOST, req)
         self.hb_address = (LOCALHOST, hb)
 
-    def shutdown_kernel(self):
+    def shutdown_kernel(self, restart=False):
         """ Attempts to the stop the kernel process cleanly. If the kernel
         cannot be stopped, it is killed, if possible.
         """
@@ -759,7 +759,7 @@ def shutdown_kernel(self):
         # Don't send any additional kernel kill messages immediately, to give
         # the kernel a chance to properly execute shutdown actions. Wait for at
         # most 1s, checking every 0.1s.
-        self.xreq_channel.shutdown()
+        self.xreq_channel.shutdown(restart=restart)
         for i in range(10):
             if self.is_alive:
                 time.sleep(0.1)
@@ -793,7 +793,7 @@ def restart_kernel(self, now=False):
                 if now:
                     self.kill_kernel()
                 else:
-                    self.shutdown_kernel()
+                    self.shutdown_kernel(restart=True)
             self.start_kernel(**self._launch_args)
 
             # FIXME: Messages get dropped in Windows due to probable ZMQ bug

IPython/zmq/pykernel.py

@@ -60,7 +60,7 @@ def __init__(self, **kwargs):
 
         # Build dict of handlers for message types
         msg_types = [ 'execute_request', 'complete_request', 
-                      'object_info_request' ]
+                      'object_info_request', 'shutdown_request' ]
         self.handlers = {}
         for msg_type in msg_types:
             self.handlers[msg_type] = getattr(self, msg_type)
@@ -163,6 +163,16 @@ def object_info_request(self, ident, parent):
                                 object_info, parent, ident)
         print >> sys.__stdout__, msg
 
+    def shutdown_request(self, ident, parent):
+        content = dict(parent['content'])
+        msg = self.session.send(self.reply_socket, 'shutdown_reply',
+                                content, parent, ident)
+        msg = self.session.send(self.pub_socket, 'shutdown_reply',
+                                content, parent, ident)
+        print >> sys.__stdout__, msg
+        time.sleep(0.1)
+        sys.exit(0)
+
     #---------------------------------------------------------------------------
     # Protected interface
     #---------------------------------------------------------------------------

docs/source/development/messaging.txt

@@ -663,11 +663,13 @@ be sent, so the content dict is empty.
 Message type: ``shutdown_request``::
 
     content = {
+        'restart' : bool # whether the shutdown is final, or precedes a restart
     }
 
 Message type: ``shutdown_reply``::
 
     content = {
+        'restart' : bool # whether the shutdown is final, or precedes a restart
     }
 
 .. Note::