IPython/frontend/qt/console/ipythonqt.py

""" 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

#-----------------------------------------------------------------------------
# Network Constants
#-----------------------------------------------------------------------------

from IPython.utils.localinterfaces import LOCALHOST, LOCAL_IPS

#-----------------------------------------------------------------------------
# Classes
#-----------------------------------------------------------------------------

class MainWindow(QtGui.QMainWindow):

    #---------------------------------------------------------------------------
    # 'object' interface
    #---------------------------------------------------------------------------
    
    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 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 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()
            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:
                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 not args.existing:
        # if not args.ip in LOCAL_IPS+ALL_ALIAS:
        #     raise ValueError("Must bind a local ip, such as: %s"%LOCAL_IPS)
        
        kwargs = dict(ip=args.ip)
        if args.pure:
            kwargs['ipython']=False
        elif args.pylab:
            kwargs['pylab']=args.pylab
            
        kernel_manager.start_kernel(**kwargs)
    kernel_manager.start_channels()

    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, 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()