prevent remote frontends from closing the kernel

IPython/frontend/qt/console/ipythonqt.py

@@ -1,160 +1,178 b''
 """ A minimal application using the Qt console-style IPython frontend.
 """
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Systemm library imports
 from PyQt4 import QtGui
 
 # Local imports
 from IPython.external.argparse import ArgumentParser
 from IPython.frontend.qt.console.frontend_widget import FrontendWidget
 from IPython.frontend.qt.console.ipython_widget import IPythonWidget
 from IPython.frontend.qt.console.rich_ipython_widget import RichIPythonWidget
 from IPython.frontend.qt.kernelmanager import QtKernelManager
 
 #-----------------------------------------------------------------------------
 # Constants
 #-----------------------------------------------------------------------------
 
 LOCALHOST = '127.0.0.1'
 
 #-----------------------------------------------------------------------------
 # Classes
 #-----------------------------------------------------------------------------
 
 class MainWindow(QtGui.QMainWindow):
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
-    def __init__(self, app, frontend, existing=False):
+    def __init__(self, app, frontend, existing=False, may_close=True):
         """ 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.
+        If existing is True, then this Console does not own the Kernel.
+        
+        If may_close is True, then this Console is permitted to close the kernel
         """
         super(MainWindow, self).__init__()
         self._app = app
         self._frontend = frontend
         self._existing = existing
+        if not existing:
+            self._may_close = may_close
+        else:
+            self._may_close = True
         self._frontend.exit_requested.connect(self.close)
         self.setCentralWidget(frontend)
     
     #---------------------------------------------------------------------------
     # QWidget interface
     #---------------------------------------------------------------------------
     
     def closeEvent(self, event):
         """ Reimplemented to prompt the user and close the kernel cleanly.
         """
         kernel_manager = self._frontend.kernel_manager
         if kernel_manager and kernel_manager.channels_running:
             title = self.window().windowTitle()
-            reply = QtGui.QMessageBox.question(self, title,
-                "You are closing this Console window."+
-                "\nWould you like to quit the Kernel and all attached Consoles as well?",
-                'Cancel', 'No, just this Console', 'Yes, quit everything')
-            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)
-                    self.deleteLater()
-                event.accept()
+            if self._may_close:
+                reply = QtGui.QMessageBox.question(self, title,
+                    "You are closing this Console window."+
+                    "\nWould you like to quit the Kernel and all attached Consoles as well?",
+                    'Cancel', 'No, just this Console', 'Yes, quit everything')
+                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)
+                        self.deleteLater()
+                    event.accept()
+                else:
+                    event.ignore()
             else:
-                event.ignore()
+                reply = QtGui.QMessageBox.question(self, title,
+                    "Are you sure you want to close this Console?\n"+
+                    "The Kernel and other Consoles will remain active.",
+                    QtGui.QMessageBox.Yes, QtGui.QMessageBox.No
+                    )
+                if reply == QtGui.QMessageBox.Yes:
+                    event.accept()
+                else:
+                    event.ignore()
+            
 
 #-----------------------------------------------------------------------------
 # Main entry point
 #-----------------------------------------------------------------------------
 
 def main():
     """ Entry point for application.
     """
     # Parse command line arguments.
     parser = ArgumentParser()
     kgroup = parser.add_argument_group('kernel options')
     kgroup.add_argument('-e', '--existing', action='store_true',
                         help='connect to an existing kernel')
     kgroup.add_argument('--ip', type=str, default=LOCALHOST,
                         help='set the kernel\'s IP address [default localhost]')
     kgroup.add_argument('--xreq', type=int, metavar='PORT', default=0,
                         help='set the XREQ channel port [default random]')
     kgroup.add_argument('--sub', type=int, metavar='PORT', default=0,
                         help='set the SUB channel port [default random]')
     kgroup.add_argument('--rep', type=int, metavar='PORT', default=0,
                         help='set the REP channel port [default random]')
     kgroup.add_argument('--hb', type=int, metavar='PORT', default=0,
                         help='set the heartbeat port [default: random]')
 
     egroup = kgroup.add_mutually_exclusive_group()
     egroup.add_argument('--pure', action='store_true', help = \
                         'use a pure Python kernel instead of an IPython kernel')
     egroup.add_argument('--pylab', type=str, metavar='GUI', nargs='?', 
                        const='auto', help = \
         "Pre-load matplotlib and numpy for interactive use. If GUI is not \
          given, the GUI backend is matplotlib's, otherwise use one of: \
          ['tk', 'gtk', 'qt', 'wx', 'inline'].")
 
     wgroup = parser.add_argument_group('widget options')
     wgroup.add_argument('--paging', type=str, default='inside',
                         choices = ['inside', 'hsplit', 'vsplit', 'none'],
                         help='set the paging style [default inside]')
     wgroup.add_argument('--rich', action='store_true',
                         help='enable rich text support')
     wgroup.add_argument('--gui-completion', action='store_true',
                         help='use a GUI widget for tab completion')
 
     args = parser.parse_args()
 
     # Don't let Qt or ZMQ swallow KeyboardInterupts.
     import signal
     signal.signal(signal.SIGINT, signal.SIG_DFL)
 
     # Create a KernelManager and start a kernel.
     kernel_manager = QtKernelManager(xreq_address=(args.ip, args.xreq),
                                      sub_address=(args.ip, args.sub),
                                      rep_address=(args.ip, args.rep),
                                      hb_address=(args.ip, args.hb))
-    if args.ip == LOCALHOST and not args.existing:
+    if not args.existing:
         if args.pure:
             kernel_manager.start_kernel(ipython=False)
         elif args.pylab:
             kernel_manager.start_kernel(pylab=args.pylab)
         else:
             kernel_manager.start_kernel()
     kernel_manager.start_channels()
 
-    local_kernel = (args.ip == LOCALHOST)
+    local_kernel = (not args.existing) or args.ip == LOCALHOST
     # Create the widget.
     app = QtGui.QApplication([])
     if args.pure:
         kind = 'rich' if args.rich else 'plain'
         widget = FrontendWidget(kind=kind, paging=args.paging, local_kernel=local_kernel)
     elif args.rich or args.pylab:
         widget = RichIPythonWidget(paging=args.paging, local_kernel=local_kernel)
     else:
         widget = IPythonWidget(paging=args.paging, local_kernel=local_kernel)
     widget.gui_completion = args.gui_completion
     widget.kernel_manager = kernel_manager
 
     # Create the main window.
-    window = MainWindow(app, widget, args.existing)
+    window = MainWindow(app, widget, args.existing, may_close=local_kernel)
     window.setWindowTitle('Python' if args.pure else 'IPython')
     window.show()
 
     # Start the application main loop.
     app.exec_()
 
 
 if __name__ == '__main__':
     main()