* The SVG payload matplotlib backend now works.

* Added RichIPythonWidget, which supports plot payloads.
* Added Qt console demo applicaton.
* Fixed calltips not being resized properly.

IPython/frontend/qt/console/demo.py

@@ -0,0 +1,54 b''
+""" A demo of Qt console-style IPython frontend.
+"""
+
+# Systemm library imports
+from PyQt4 import QtCore, QtGui
+
+# Local imports
+from IPython.external.argparse import ArgumentParser
+from IPython.frontend.qt.kernelmanager import QtKernelManager
+from ipython_widget import IPythonWidget
+from rich_ipython_widget import RichIPythonWidget
+
+
+def main():
+    """ Entry point for demo.
+    """
+    # Parse command line arguments.
+    parser = ArgumentParser()
+    parser.add_argument('--pylab', action='store_true',
+                        help='start kernel with pylab enabled')
+    parser.add_argument('--rich', action='store_true',
+                        help='use rich text frontend')
+    namespace = 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()
+    if namespace.pylab:
+        if namespace.rich:
+            kernel_manager.start_kernel(pylab='payload-svg')
+        else:
+            kernel_manager.start_kernel(pylab='qt4')
+    else:
+        kernel_manager.start_kernel()
+    kernel_manager.start_channels()
+
+    # Launch the application.
+    app = QtGui.QApplication([])
+    if namespace.rich:
+        widget = RichIPythonWidget()
+    else:
+        widget = IPythonWidget()
+    widget.kernel_manager = kernel_manager
+    widget.setWindowTitle('Python')
+    widget.resize(640, 480)
+    widget.show()
+    app.exec_()
+
+
+if __name__ == '__main__':
+    main()

IPython/frontend/qt/console/rich_ipython_widget.py

@@ -0,0 +1,43 b''
+# System library imports
+from PyQt4 import QtCore, QtGui
+
+# Local imports
+from IPython.frontend.qt.util import image_from_svg
+from ipython_widget import IPythonWidget
+
+
+class RichIPythonWidget(IPythonWidget):
+    """ An IPythonWidget that supports rich text, including lists, images, and
+        tables. Note that raw performance will be reduced compared to the plain
+        text version.
+    """
+
+    #---------------------------------------------------------------------------
+    # 'QObject' interface
+    #---------------------------------------------------------------------------
+
+    def __init__(self, parent=None):
+        """ Create a RichIPythonWidget.
+        """
+        super(RichIPythonWidget, self).__init__(kind='rich', parent=parent)
+    
+    #---------------------------------------------------------------------------
+    # 'FrontendWidget' interface
+    #---------------------------------------------------------------------------
+
+    def _handle_execute_payload(self, payload):
+        """ Reimplemented to handle pylab plot payloads.
+        """
+        super(RichIPythonWidget, self)._handle_execute_payload(payload)
+
+        plot_payload = payload.get('plot', None)
+        if plot_payload and plot_payload['format'] == 'svg':
+            try:
+                image = image_from_svg(plot_payload['data'])
+            except ValueError:
+                self._append_plain_text('Received invalid plot data.')
+            else:
+                cursor = self._get_end_cursor()
+                cursor.insertBlock()
+                cursor.insertImage(image)
+                cursor.insertBlock()

IPython/frontend/qt/console/call_tip_widget.py

@@ -1,165 +1,163 b''
 # Standard library imports
 import re
 from textwrap import dedent
 
 # System library imports
 from PyQt4 import QtCore, QtGui
 
 
 class CallTipWidget(QtGui.QLabel):
     """ Shows call tips by parsing the current text of Q[Plain]TextEdit.
     """
 
     #--------------------------------------------------------------------------
     # 'QObject' interface
     #--------------------------------------------------------------------------
 
     def __init__(self, parent):
         """ Create a call tip manager that is attached to the specified Qt
             text edit widget.
         """
         assert isinstance(parent, (QtGui.QTextEdit, QtGui.QPlainTextEdit))
         QtGui.QLabel.__init__(self, parent, QtCore.Qt.ToolTip)
 
         self.setFont(parent.document().defaultFont())
         self.setForegroundRole(QtGui.QPalette.ToolTipText)
         self.setBackgroundRole(QtGui.QPalette.ToolTipBase)
         self.setPalette(QtGui.QToolTip.palette())
 
         self.setAlignment(QtCore.Qt.AlignLeft)
         self.setIndent(1)
         self.setFrameStyle(QtGui.QFrame.NoFrame)
         self.setMargin(1 + self.style().pixelMetric(
                 QtGui.QStyle.PM_ToolTipLabelFrameWidth, None, self))
         self.setWindowOpacity(self.style().styleHint(
                 QtGui.QStyle.SH_ToolTipLabel_Opacity, None, self) / 255.0)
 
     def eventFilter(self, obj, event):
         """ Reimplemented to hide on certain key presses and on parent focus
             changes.
         """
         if obj == self.parent():
             etype = event.type()
             if (etype == QtCore.QEvent.KeyPress and
                 event.key() in (QtCore.Qt.Key_Enter, QtCore.Qt.Key_Return, 
                                 QtCore.Qt.Key_Escape)):
                 self.hide()
             elif etype == QtCore.QEvent.FocusOut:
                 self.hide()
 
         return QtGui.QLabel.eventFilter(self, obj, event)
 
     #--------------------------------------------------------------------------
     # 'QWidget' interface
     #--------------------------------------------------------------------------
 
     def hideEvent(self, event):
         """ Reimplemented to disconnect signal handlers and event filter.
         """
         QtGui.QLabel.hideEvent(self, event)
         parent = self.parent()
         parent.cursorPositionChanged.disconnect(self._cursor_position_changed)
         parent.removeEventFilter(self)
 
     def paintEvent(self, event):
         """ Reimplemented to paint the background panel.
         """
         painter = QtGui.QStylePainter(self)
         option = QtGui.QStyleOptionFrame()
         option.init(self)
         painter.drawPrimitive(QtGui.QStyle.PE_PanelTipLabel, option)
         painter.end()
 
         QtGui.QLabel.paintEvent(self, event)
 
     def showEvent(self, event):
         """ Reimplemented to connect signal handlers and event filter.
         """
         QtGui.QLabel.showEvent(self, event)
         parent = self.parent()
         parent.cursorPositionChanged.connect(self._cursor_position_changed)
         parent.installEventFilter(self)
 
     #--------------------------------------------------------------------------
     # 'CallTipWidget' interface
     #--------------------------------------------------------------------------
 
     def show_docstring(self, doc, maxlines=20):
         """ Attempts to show the specified docstring at the current cursor
             location. The docstring is dedented and possibly truncated for
             length.
         """
         doc = dedent(doc.rstrip()).lstrip()
         match = re.match("(?:[^\n]*\n){%i}" % maxlines, doc)
         if match:
             doc = doc[:match.end()] + '\n[Documentation continues...]'
         return self.show_tip(doc)
 
     def show_tip(self, tip):
         """ Attempts to show the specified tip at the current cursor location.
         """
         text_edit = self.parent()
         document = text_edit.document()
         cursor = text_edit.textCursor()
         search_pos = cursor.position() - 1
         self._start_position, _ = self._find_parenthesis(search_pos, 
                                                          forward=False)
         if self._start_position == -1:
             return False
     
         point = text_edit.cursorRect(cursor).bottomRight()
         point = text_edit.mapToGlobal(point)
         self.move(point)
         self.setText(tip)
-        if self.isVisible():
             self.resize(self.sizeHint())
-        else:
             self.show()
         return True
             
     #--------------------------------------------------------------------------
     # Protected interface
     #--------------------------------------------------------------------------
 
     def _find_parenthesis(self, position, forward=True):
         """ If 'forward' is True (resp. False), proceed forwards
             (resp. backwards) through the line that contains 'position' until an
             unmatched closing (resp. opening) parenthesis is found. Returns a
             tuple containing the position of this parenthesis (or -1 if it is
             not found) and the number commas (at depth 0) found along the way.
         """
         commas = depth = 0
         document = self.parent().document()
         qchar = document.characterAt(position)
         while (position > 0 and qchar.isPrint() and 
                # Need to check explicitly for line/paragraph separators:
                qchar.unicode() not in (0x2028, 0x2029)):
             char = qchar.toAscii()
             if char == ',' and depth == 0:
                 commas += 1
             elif char == ')':
                 if forward and depth == 0:
                     break
                 depth += 1
             elif char == '(':
                 if not forward and depth == 0:
                     break
                 depth -= 1
             position += 1 if forward else -1
             qchar = document.characterAt(position)
         else:
             position = -1
         return position, commas
 
     #------ Signal handlers ----------------------------------------------------
 
     def _cursor_position_changed(self):
         """ Updates the tip based on user cursor movement.
         """
         cursor = self.parent().textCursor()
         if cursor.position() <= self._start_position:
             self.hide()
         else:
             position, commas = self._find_parenthesis(self._start_position + 1)
             if position != -1:
                 self.hide()

IPython/frontend/qt/console/frontend_widget.py

@@ -1,369 +1,376 b''
 # Standard library imports
 import signal
 import sys
 
 # System library imports
 from pygments.lexers import PythonLexer
 from PyQt4 import QtCore, QtGui
 import zmq
 
 # Local imports
 from IPython.core.inputsplitter import InputSplitter
 from call_tip_widget import CallTipWidget
 from completion_lexer import CompletionLexer
 from console_widget import HistoryConsoleWidget
 from pygments_highlighter import PygmentsHighlighter
 
 
 class FrontendHighlighter(PygmentsHighlighter):
     """ A PygmentsHighlighter that can be turned on and off and that ignores
         prompts.
     """
 
     def __init__(self, frontend):
         super(FrontendHighlighter, self).__init__(frontend._control.document())
         self._current_offset = 0
         self._frontend = frontend
         self.highlighting_on = False
 
     def highlightBlock(self, qstring):
         """ Highlight a block of text. Reimplemented to highlight selectively.
         """
         if not self.highlighting_on:
             return
 
         # The input to this function is unicode string that may contain
         # paragraph break characters, non-breaking spaces, etc. Here we acquire
         # the string as plain text so we can compare it.
         current_block = self.currentBlock()
         string = self._frontend._get_block_plain_text(current_block)
 
         # Decide whether to check for the regular or continuation prompt.
         if current_block.contains(self._frontend._prompt_pos):
             prompt = self._frontend._prompt
         else:
             prompt = self._frontend._continuation_prompt
 
         # Don't highlight the part of the string that contains the prompt.
         if string.startswith(prompt):
             self._current_offset = len(prompt)
             qstring.remove(0, len(prompt))
         else:
             self._current_offset = 0
 
         PygmentsHighlighter.highlightBlock(self, qstring)
 
     def setFormat(self, start, count, format):
         """ Reimplemented to highlight selectively.
         """
         start += self._current_offset
         PygmentsHighlighter.setFormat(self, start, count, format)
 
 
 class FrontendWidget(HistoryConsoleWidget):
     """ A Qt frontend for a generic Python kernel.
     """
    
     # Emitted when an 'execute_reply' is received from the kernel.
     executed = QtCore.pyqtSignal(object)
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
     def __init__(self, *args, **kw):
         super(FrontendWidget, self).__init__(*args, **kw)
 
         # FrontendWidget protected variables.
         self._call_tip_widget = CallTipWidget(self._control)
         self._completion_lexer = CompletionLexer(PythonLexer())
         self._hidden = True
         self._highlighter = FrontendHighlighter(self)
         self._input_splitter = InputSplitter(input_mode='replace')
         self._kernel_manager = None
 
         # Configure the ConsoleWidget.
         self.tab_width = 4
         self._set_continuation_prompt('... ')
 
         # Connect signal handlers.
         document = self._control.document()
         document.contentsChange.connect(self._document_contents_change)
 
     #---------------------------------------------------------------------------
     # 'ConsoleWidget' abstract interface
     #---------------------------------------------------------------------------
 
     def _is_complete(self, source, interactive):
         """ Returns whether 'source' can be completely processed and a new
             prompt created. When triggered by an Enter/Return key press,
             'interactive' is True; otherwise, it is False.
         """
         complete = self._input_splitter.push(source.expandtabs(4))
         if interactive:
             complete = not self._input_splitter.push_accepts_more()
         return complete
 
     def _execute(self, source, hidden):
         """ Execute 'source'. If 'hidden', do not show any output.
         """
         self.kernel_manager.xreq_channel.execute(source)
         self._hidden = hidden
 
     def _execute_interrupt(self):
         """ Attempts to stop execution. Returns whether this method has an
             implementation.
         """
         self._interrupt_kernel()
         return True
         
     def _prompt_started_hook(self):
         """ Called immediately after a new prompt is displayed.
         """
         if not self._reading:
             self._highlighter.highlighting_on = True
 
             # Auto-indent if this is a continuation prompt.
             if self._get_prompt_cursor().blockNumber() != \
                     self._get_end_cursor().blockNumber():
                 spaces = self._input_splitter.indent_spaces
                 self._append_plain_text('\t' * (spaces / self.tab_width))
                 self._append_plain_text(' ' * (spaces % self.tab_width))
 
     def _prompt_finished_hook(self):
         """ Called immediately after a prompt is finished, i.e. when some input
             will be processed and a new prompt displayed.
         """
         if not self._reading:
             self._highlighter.highlighting_on = False
 
     def _tab_pressed(self):
         """ Called when the tab key is pressed. Returns whether to continue
             processing the event.
         """
         self._keep_cursor_in_buffer()
         cursor = self._get_cursor()
         return not self._complete()
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' interface
     #---------------------------------------------------------------------------
 
     def execute_file(self, path, hidden=False):
         """ Attempts to execute file with 'path'. If 'hidden', no output is
             shown.
         """
         self.execute('execfile("%s")' % path, hidden=hidden)
 
     def _get_kernel_manager(self):
         """ Returns the current kernel manager.
         """
         return self._kernel_manager
 
     def _set_kernel_manager(self, kernel_manager):
         """ Disconnect from the current kernel manager (if any) and set a new
             kernel manager.
         """
         # Disconnect the old kernel manager, if necessary.
         if self._kernel_manager is not None:
             self._kernel_manager.started_channels.disconnect(
                 self._started_channels)
             self._kernel_manager.stopped_channels.disconnect(
                 self._stopped_channels)
 
             # Disconnect the old kernel manager's channels.
             sub = self._kernel_manager.sub_channel
             xreq = self._kernel_manager.xreq_channel
             rep = self._kernel_manager.rep_channel
             sub.message_received.disconnect(self._handle_sub)
             xreq.execute_reply.disconnect(self._handle_execute_reply)
             xreq.complete_reply.disconnect(self._handle_complete_reply)
             xreq.object_info_reply.disconnect(self._handle_object_info_reply)
             rep.input_requested.disconnect(self._handle_req)
 
             # Handle the case where the old kernel manager is still listening.
             if self._kernel_manager.channels_running:
                 self._stopped_channels()
 
         # Set the new kernel manager.
         self._kernel_manager = kernel_manager
         if kernel_manager is None:
             return
 
         # Connect the new kernel manager.
         kernel_manager.started_channels.connect(self._started_channels)
         kernel_manager.stopped_channels.connect(self._stopped_channels)
 
         # Connect the new kernel manager's channels.
         sub = kernel_manager.sub_channel
         xreq = kernel_manager.xreq_channel
         rep = kernel_manager.rep_channel
         sub.message_received.connect(self._handle_sub)
         xreq.execute_reply.connect(self._handle_execute_reply)
         xreq.complete_reply.connect(self._handle_complete_reply)
         xreq.object_info_reply.connect(self._handle_object_info_reply)
         rep.input_requested.connect(self._handle_req)
         
         # Handle the case where the kernel manager started channels before
         # we connected.
         if kernel_manager.channels_running:
             self._started_channels()
 
     kernel_manager = property(_get_kernel_manager, _set_kernel_manager)
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' protected interface
     #---------------------------------------------------------------------------
 
     def _call_tip(self):
         """ Shows a call tip, if appropriate, at the current cursor location.
         """
         # Decide if it makes sense to show a call tip
         cursor = self._get_cursor()
         cursor.movePosition(QtGui.QTextCursor.Left)
         document = self._control.document()
         if document.characterAt(cursor.position()).toAscii() != '(':
             return False
         context = self._get_context(cursor)
         if not context:
             return False
 
         # Send the metadata request to the kernel
         name = '.'.join(context)
         self._call_tip_id = self.kernel_manager.xreq_channel.object_info(name)
         self._call_tip_pos = self._get_cursor().position()
         return True
 
     def _complete(self):
         """ Performs completion at the current cursor location.
         """
         # Decide if it makes sense to do completion
         context = self._get_context()
         if not context:
             return False
 
         # Send the completion request to the kernel
         text = '.'.join(context)
         self._complete_id = self.kernel_manager.xreq_channel.complete(
             text, self.input_buffer_cursor_line, self.input_buffer)
         self._complete_pos = self._get_cursor().position()
         return True
 
     def _get_banner(self):
         """ Gets a banner to display at the beginning of a session.
         """
         banner = 'Python %s on %s\nType "help", "copyright", "credits" or ' \
             '"license" for more information.'
         return banner % (sys.version, sys.platform)
 
     def _get_context(self, cursor=None):
         """ Gets the context at the current cursor location.
         """
         if cursor is None:
             cursor = self._get_cursor()
         cursor.movePosition(QtGui.QTextCursor.StartOfLine, 
                             QtGui.QTextCursor.KeepAnchor)
         text = str(cursor.selection().toPlainText())
         return self._completion_lexer.get_context(text)
 
     def _interrupt_kernel(self):
         """ Attempts to the interrupt the kernel.
         """
         if self.kernel_manager.has_kernel:
             self.kernel_manager.signal_kernel(signal.SIGINT)
         else:
             self._append_plain_text('Kernel process is either remote or '
                                     'unspecified. Cannot interrupt.\n')
 
     def _show_interpreter_prompt(self):
         """ Shows a prompt for the interpreter.
         """
         self._show_prompt('>>> ')
 
     #------ Signal handlers ----------------------------------------------------
 
     def _started_channels(self):
         """ Called when the kernel manager has started listening.
         """
         self._reset()
         self._append_plain_text(self._get_banner())
         self._show_interpreter_prompt()
 
     def _stopped_channels(self):
         """ Called when the kernel manager has stopped listening.
         """
         # FIXME: Print a message here?
         pass
 
     def _document_contents_change(self, position, removed, added):
         """ Called whenever the document's content changes. Display a call tip
             if appropriate.
         """
         # Calculate where the cursor should be *after* the change:
         position += added
 
         document = self._control.document()
         if position == self._get_cursor().position():
             self._call_tip()
 
     def _handle_req(self, req):
         # Make sure that all output from the SUB channel has been processed
         # before entering readline mode.
         self.kernel_manager.sub_channel.flush()
 
         def callback(line):
             self.kernel_manager.rep_channel.input(line)
         self._readline(req['content']['prompt'], callback=callback)
 
     def _handle_sub(self, omsg):
         if self._hidden:
             return
         handler = getattr(self, '_handle_%s' % omsg['msg_type'], None)
         if handler is not None:
             handler(omsg)
 
     def _handle_pyout(self, omsg):
         self._append_plain_text(omsg['content']['data'] + '\n')
 
     def _handle_stream(self, omsg):
         self._append_plain_text(omsg['content']['data'])
         self._control.moveCursor(QtGui.QTextCursor.End)
         
     def _handle_execute_reply(self, reply):
         if self._hidden:
             return
 
         # Make sure that all output from the SUB channel has been processed
         # before writing a new prompt.
         self.kernel_manager.sub_channel.flush()
 
-        status = reply['content']['status']
-        if status == 'error':
+        content = reply['content']
+        status = content['status']
+        if status == 'ok':
+            self._handle_execute_payload(content['payload'])
+        elif status == 'error':
             self._handle_execute_error(reply)
         elif status == 'aborted':
             text = "ERROR: ABORTED\n"
             self._append_plain_text(text)
+
         self._hidden = True
         self._show_interpreter_prompt()
         self.executed.emit(reply)
 
     def _handle_execute_error(self, reply):
         content = reply['content']
         traceback = ''.join(content['traceback'])
         self._append_plain_text(traceback)
 
+    def _handle_execute_payload(self, payload):
+        pass
+
     def _handle_complete_reply(self, rep):
         cursor = self._get_cursor()
         if rep['parent_header']['msg_id'] == self._complete_id and \
                 cursor.position() == self._complete_pos:
             text = '.'.join(self._get_context())
             cursor.movePosition(QtGui.QTextCursor.Left, n=len(text))
             self._complete_with_items(cursor, rep['content']['matches'])
 
     def _handle_object_info_reply(self, rep):
         cursor = self._get_cursor()
         if rep['parent_header']['msg_id'] == self._call_tip_id and \
                 cursor.position() == self._call_tip_pos:
             doc = rep['content']['docstring']
             if doc:
                 self._call_tip_widget.show_docstring(doc)

IPython/frontend/qt/console/ipython_widget.py

@@ -1,206 +1,184 b''
 # System library imports
 from PyQt4 import QtCore, QtGui
 
 # Local imports
 from IPython.core.usage import default_banner
 from frontend_widget import FrontendWidget
 
 
 class IPythonWidget(FrontendWidget):
     """ A FrontendWidget for an IPython kernel.
     """
 
     # The default stylesheet: black text on a white background.
     default_stylesheet = """
         .error { color: red; }
         .in-prompt { color: navy; }
         .in-prompt-number { font-weight: bold; }
         .out-prompt { color: darkred; }
         .out-prompt-number { font-weight: bold; }
     """
 
     # A dark stylesheet: white text on a black background.
     dark_stylesheet = """
         QPlainTextEdit { background-color: black; color: white }
         QFrame { border: 1px solid grey; }
         .error { color: red; }
         .in-prompt { color: lime; }
         .in-prompt-number { color: lime; font-weight: bold; }
         .out-prompt { color: red; }
         .out-prompt-number { color: red; font-weight: bold; }
     """
 
     # Default prompts.
     in_prompt = '<br/>In [<span class="in-prompt-number">%i</span>]: '
     out_prompt = 'Out[<span class="out-prompt-number">%i</span>]: '
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
     def __init__(self, *args, **kw):
         super(IPythonWidget, self).__init__(*args, **kw)
 
         # Initialize protected variables.
         self._previous_prompt_blocks = []
         self._prompt_count = 0
 
         # Set a default stylesheet.
         self.reset_styling()
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' interface
     #---------------------------------------------------------------------------
 
     def execute_file(self, path, hidden=False):
         """ Reimplemented to use the 'run' magic.
         """
         self.execute('run %s' % path, hidden=hidden)
 
     #---------------------------------------------------------------------------
     # 'FrontendWidget' protected interface
     #---------------------------------------------------------------------------
 
     def _get_banner(self):
         """ Reimplemented to return IPython's default banner.
         """
         return default_banner
 
     def _show_interpreter_prompt(self):
         """ Reimplemented for IPython-style prompts.
         """
         # Update old prompt numbers if necessary.
         previous_prompt_number = self._prompt_count
         if previous_prompt_number != self._prompt_count:
             for i, (block, length) in enumerate(self._previous_prompt_blocks):
                 if block.isValid():
                     cursor = QtGui.QTextCursor(block)
                     cursor.movePosition(QtGui.QTextCursor.Right,
                                         QtGui.QTextCursor.KeepAnchor, length-1)
                     if i == 0:
                         prompt = self._make_in_prompt(previous_prompt_number)
                     else:
                         prompt = self._make_out_prompt(previous_prompt_number)
                     self._insert_html(cursor, prompt)
         self._previous_prompt_blocks = []
 
         # Show a new prompt.
         self._prompt_count += 1
         self._show_prompt(self._make_in_prompt(self._prompt_count), html=True)
         self._save_prompt_block()
 
         # Update continuation prompt to reflect (possibly) new prompt length.
         self._set_continuation_prompt(
             self._make_continuation_prompt(self._prompt), html=True)
 
     #------ Signal handlers ----------------------------------------------------
 
     def _handle_execute_error(self, reply):
         """ Reimplemented for IPython-style traceback formatting.
         """
         content = reply['content']
         traceback_lines = content['traceback'][:]
         traceback = ''.join(traceback_lines)
         traceback = traceback.replace(' ', '&nbsp;')
         traceback = traceback.replace('\n', '<br/>')
 
         ename = content['ename']
         ename_styled = '<span class="error">%s</span>' % ename
         traceback = traceback.replace(ename, ename_styled)
 
         self._append_html(traceback)
 
     def _handle_pyout(self, omsg):
         """ Reimplemented for IPython-style "display hook".
         """
         self._append_html(self._make_out_prompt(self._prompt_count))
         self._save_prompt_block()
         
         self._append_plain_text(omsg['content']['data'] + '\n')
 
     #---------------------------------------------------------------------------
     # 'IPythonWidget' interface
     #---------------------------------------------------------------------------
 
     def reset_styling(self):
         """ Restores the default IPythonWidget styling.
         """
         self.set_styling(self.default_stylesheet, syntax_style='default')
         #self.set_styling(self.dark_stylesheet, syntax_style='monokai')
 
     def set_styling(self, stylesheet, syntax_style=None):
         """ Sets the IPythonWidget styling.
 
         Parameters:
         -----------
         stylesheet : str
             A CSS stylesheet. The stylesheet can contain classes for:
                 1. Qt: QPlainTextEdit, QFrame, QWidget, etc
                 2. Pygments: .c, .k, .o, etc (see PygmentsHighlighter)
                 3. IPython: .error, .in-prompt, .out-prompt, etc.
 
         syntax_style : str or None [default None]
             If specified, use the Pygments style with given name. Otherwise, 
             the stylesheet is queried for Pygments style information.
         """
         self.setStyleSheet(stylesheet)
         self._control.document().setDefaultStyleSheet(stylesheet)
 
         if syntax_style is None:
             self._highlighter.set_style_sheet(stylesheet)
         else:
             self._highlighter.set_style(syntax_style)
 
     #---------------------------------------------------------------------------
     # 'IPythonWidget' protected interface
     #---------------------------------------------------------------------------
 
     def _make_in_prompt(self, number):
         """ Given a prompt number, returns an HTML In prompt.
         """
         body = self.in_prompt % number
         return '<span class="in-prompt">%s</span>' % body
 
     def _make_continuation_prompt(self, prompt):
         """ Given a plain text version of an In prompt, returns an HTML
             continuation prompt.
         """
         end_chars = '...: '
         space_count = len(prompt.lstrip('\n')) - len(end_chars)
         body = '&nbsp;' * space_count + end_chars
         return '<span class="in-prompt">%s</span>' % body
         
     def _make_out_prompt(self, number):
         """ Given a prompt number, returns an HTML Out prompt.
         """
         body = self.out_prompt % number
         return '<span class="out-prompt">%s</span>' % body
 
     def _save_prompt_block(self):
         """ Assuming a prompt has just been written at the end of the buffer,
             store the QTextBlock that contains it and its length.
         """
         block = self._control.document().lastBlock()
         self._previous_prompt_blocks.append((block, block.length()))
-
-
-if __name__ == '__main__':
-    from IPython.frontend.qt.kernelmanager import QtKernelManager
-
-    # Don't let Qt or ZMQ swallow KeyboardInterupts.
-    import signal
-    signal.signal(signal.SIGINT, signal.SIG_DFL)
-
-    # Create a KernelManager.
-    kernel_manager = QtKernelManager()
-    kernel_manager.start_kernel()
-    kernel_manager.start_channels()
-
-    # Launch the application.
-    app = QtGui.QApplication([])
-    widget = IPythonWidget()
-    widget.kernel_manager = kernel_manager
-    widget.setWindowTitle('Python')
-    widget.resize(640, 480)
-    widget.show()
-    app.exec_()

IPython/frontend/qt/kernelmanager.py

@@ -1,184 +1,180 b''
 """ Defines a KernelManager that provides signals and slots.
 """
 
 # System library imports.
 from PyQt4 import QtCore
 import zmq
 
 # IPython imports.
 from IPython.zmq.kernelmanager import KernelManager, SubSocketChannel, \
     XReqSocketChannel, RepSocketChannel
 from util import MetaQObjectHasTraits
 
 # When doing multiple inheritance from QtCore.QObject and other classes
 # the calling of the parent __init__'s is a subtle issue:
 # * QtCore.QObject does not call super so you can't use super and put
 #   QObject first in the inheritance list.
 # * QtCore.QObject.__init__ takes 1 argument, the parent. So if you are going
 #   to use super, any class that comes before QObject must pass it something
 #   reasonable.
 # In summary, I don't think using super in these situations will work.
 # Instead we will need to call the __init__ methods of both parents
 # by hand.  Not pretty, but it works.
 
 class QtSubSocketChannel(SubSocketChannel, QtCore.QObject):
 
     # Emitted when any message is received.
     message_received = QtCore.pyqtSignal(object)
 
     # Emitted when a message of type 'pyout' or 'stdout' is received.
     output_received = QtCore.pyqtSignal(object)
 
     # Emitted when a message of type 'pyerr' or 'stderr' is received.
     error_received = QtCore.pyqtSignal(object)
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
     def __init__(self, *args, **kw):
         """ Reimplemented to ensure that QtCore.QObject is initialized first.
         """
         QtCore.QObject.__init__(self)
         SubSocketChannel.__init__(self, *args, **kw)
 
     #---------------------------------------------------------------------------
     # 'SubSocketChannel' interface
     #---------------------------------------------------------------------------
     
     def call_handlers(self, msg):
         """ Reimplemented to emit signals instead of making callbacks.
         """
         # Emit the generic signal.
         self.message_received.emit(msg)
         
         # Emit signals for specialized message types.
         msg_type = msg['msg_type']
         if msg_type in ('pyout', 'stdout'):
             self.output_received.emit(msg)
         elif msg_type in ('pyerr', 'stderr'):
             self.error_received.emit(msg)
 
     def flush(self):
         """ Reimplemented to ensure that signals are dispatched immediately.
         """
         super(QtSubSocketChannel, self).flush()
         QtCore.QCoreApplication.instance().processEvents()
 
 
 class QtXReqSocketChannel(XReqSocketChannel, QtCore.QObject):
 
     # Emitted when any message is received.
     message_received = QtCore.pyqtSignal(object)
 
     # Emitted when a reply has been received for the corresponding request type.
     execute_reply = QtCore.pyqtSignal(object)
     complete_reply = QtCore.pyqtSignal(object)
     object_info_reply = QtCore.pyqtSignal(object)
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
     def __init__(self, *args, **kw):
         """ Reimplemented to ensure that QtCore.QObject is initialized first.
         """
         QtCore.QObject.__init__(self)
         XReqSocketChannel.__init__(self, *args, **kw)
 
     #---------------------------------------------------------------------------
     # 'XReqSocketChannel' interface
     #---------------------------------------------------------------------------
     
     def call_handlers(self, msg):
         """ Reimplemented to emit signals instead of making callbacks.
         """
         # Emit the generic signal.
         self.message_received.emit(msg)
         
         # Emit signals for specialized message types.
         msg_type = msg['msg_type']
         signal = getattr(self, msg_type, None)
         if signal:
             signal.emit(msg)
 
 
 class QtRepSocketChannel(RepSocketChannel, QtCore.QObject):
 
     # Emitted when any message is received.
     message_received = QtCore.pyqtSignal(object)
 
     # Emitted when an input request is received.
     input_requested = QtCore.pyqtSignal(object)
 
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
     def __init__(self, *args, **kw):
         """ Reimplemented to ensure that QtCore.QObject is initialized first.
         """
         QtCore.QObject.__init__(self)
         RepSocketChannel.__init__(self, *args, **kw)
 
     #---------------------------------------------------------------------------
     # 'RepSocketChannel' interface
     #---------------------------------------------------------------------------
 
     def call_handlers(self, msg):
         """ Reimplemented to emit signals instead of making callbacks.
         """
         # Emit the generic signal.
         self.message_received.emit(msg)
         
         # Emit signals for specialized message types.
         msg_type = msg['msg_type']
         if msg_type == 'input_request':
             self.input_requested.emit(msg)
 
 class QtKernelManager(KernelManager, QtCore.QObject):
     """ A KernelManager that provides signals and slots.
     """
 
     __metaclass__ = MetaQObjectHasTraits
 
     # Emitted when the kernel manager has started listening.
     started_channels = QtCore.pyqtSignal()
 
     # Emitted when the kernel manager has stopped listening.
     stopped_channels = QtCore.pyqtSignal()
 
     # Use Qt-specific channel classes that emit signals.
     sub_channel_class = QtSubSocketChannel
     xreq_channel_class = QtXReqSocketChannel
     rep_channel_class = QtRepSocketChannel
 
-    def __init__(self, *args, **kw):
-        QtCore.QObject.__init__(self)
-        KernelManager.__init__(self, *args, **kw)
-
     #---------------------------------------------------------------------------
     # 'object' interface
     #---------------------------------------------------------------------------
     
     def __init__(self, *args, **kw):
         """ Reimplemented to ensure that QtCore.QObject is initialized first.
         """
         QtCore.QObject.__init__(self)
         KernelManager.__init__(self, *args, **kw)
 
     #---------------------------------------------------------------------------
     # 'KernelManager' interface
     #---------------------------------------------------------------------------
     
     def start_channels(self):
         """ Reimplemented to emit signal.
         """
         super(QtKernelManager, self).start_channels()
         self.started_channels.emit()
 
     def stop_channels(self):
         """ Reimplemented to emit signal.
         """ 
         super(QtKernelManager, self).stop_channels()
         self.stopped_channels.emit()

IPython/zmq/kernel.py

@@ -1,586 +1,599 b''
 #!/usr/bin/env python
 """A simple interactive kernel that talks to a frontend over 0MQ.
 
 Things to do:
 
 * Finish implementing `raw_input`.
 * Implement `set_parent` logic. Right before doing exec, the Kernel should
   call set_parent on all the PUB objects with the message about to be executed.
 * Implement random port and security key logic.
 * Implement control messages.
 * Implement event loop and poll version.
 """
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Standard library imports.
 import __builtin__
 from code import CommandCompiler
 from cStringIO import StringIO
 import os
 import sys
 from threading import Thread
 import time
 import traceback
 
 # System library imports.
 import zmq
 
 # Local imports.
 from IPython.external.argparse import ArgumentParser
 from session import Session, Message, extract_header
 from completer import KernelCompleter
 
 #-----------------------------------------------------------------------------
 # Kernel and stream classes
 #-----------------------------------------------------------------------------
 
 class OutStream(object):
     """A file like object that publishes the stream to a 0MQ PUB socket."""
 
     # The time interval between automatic flushes, in seconds.
     flush_interval = 0.05
 
     def __init__(self, session, pub_socket, name):
         self.session = session
         self.pub_socket = pub_socket
         self.name = name
         self.parent_header = {}
         self._new_buffer()
 
     def set_parent(self, parent):
         self.parent_header = extract_header(parent)
 
     def close(self):
         self.pub_socket = None
 
     def flush(self):
         if self.pub_socket is None:
             raise ValueError(u'I/O operation on closed file')
         else:
             data = self._buffer.getvalue()
             if data:
                 content = {u'name':self.name, u'data':data}
                 msg = self.session.msg(u'stream', content=content,
                                        parent=self.parent_header)
                 print>>sys.__stdout__, Message(msg)
                 self.pub_socket.send_json(msg)
                 
                 self._buffer.close()
                 self._new_buffer()
 
     def isatty(self):
         return False
 
     def next(self):
         raise IOError('Read not supported on a write only stream.')
 
     def read(self, size=-1):
         raise IOError('Read not supported on a write only stream.')
 
     def readline(self, size=-1):
         raise IOError('Read not supported on a write only stream.')
 
     def write(self, string):
         if self.pub_socket is None:
             raise ValueError('I/O operation on closed file')
         else:
             self._buffer.write(string)
             current_time = time.time()
             if self._start <= 0:
                 self._start = current_time
             elif current_time - self._start > self.flush_interval:
                 self.flush()
 
     def writelines(self, sequence):
         if self.pub_socket is None:
             raise ValueError('I/O operation on closed file')
         else:
             for string in sequence:
                 self.write(string)
 
     def _new_buffer(self):
         self._buffer = StringIO()
         self._start = -1
 
 
 class DisplayHook(object):
 
     def __init__(self, session, pub_socket):
         self.session = session
         self.pub_socket = pub_socket
         self.parent_header = {}
 
     def __call__(self, obj):
         if obj is not None:
             __builtin__._ = obj
             msg = self.session.msg(u'pyout', {u'data':repr(obj)},
                                    parent=self.parent_header)
             self.pub_socket.send_json(msg)
 
     def set_parent(self, parent):
         self.parent_header = extract_header(parent)
 
 
 class Kernel(object):
 
     # The global kernel instance.
     _kernel = None
 
     # Maps user-friendly backend names to matplotlib backend identifiers.
     _pylab_map = { 'tk': 'TkAgg',
                    'gtk': 'GTKAgg',
                    'wx': 'WXAgg',
                    'qt': 'Qt4Agg', # qt3 not supported
                    'qt4': 'Qt4Agg',
                    'payload-svg' : \
                        'module://IPython.zmq.pylab.backend_payload_svg' }
 
     #---------------------------------------------------------------------------
     # Kernel interface
     #---------------------------------------------------------------------------
 
     def __init__(self, session, reply_socket, pub_socket, req_socket):
         self.session = session
         self.reply_socket = reply_socket
         self.pub_socket = pub_socket
         self.req_socket = req_socket
         self.user_ns = {}
         self.history = []
         self.compiler = CommandCompiler()
         self.completer = KernelCompleter(self.user_ns)
 
         # Protected variables.
         self._exec_payload = {}
         
         # Build dict of handlers for message types
         msg_types = [ 'execute_request', 'complete_request', 
                       'object_info_request' ]
         self.handlers = {}
         for msg_type in msg_types:
             self.handlers[msg_type] = getattr(self, msg_type)
 
     def add_exec_payload(self, key, value):
         """ Adds a key/value pair to the execute payload.
         """
         self._exec_payload[key] = value
 
     def activate_pylab(self, backend=None, import_all=True):
         """ Activates pylab in this kernel's namespace.
 
         Parameters:
         -----------
         backend : str, optional
             A valid backend name.
 
         import_all : bool, optional
             If true, an 'import *' is done from numpy and pylab.
         """
         # FIXME: This is adapted from IPython.lib.pylabtools.pylab_activate.
         #        Common funtionality should be refactored.
 
-        import matplotlib
-
         # We must set the desired backend before importing pylab.
+        import matplotlib
         if backend:
-            matplotlib.use(self._pylab_map[backend])
-
-        # This must be imported last in the matplotlib series, after
-        # backend/interactivity choices have been made.
-        import matplotlib.pylab as pylab
+            backend_id = self._pylab_map[backend]
+            if backend_id.startswith('module://'):
+                # Work around bug in matplotlib: matplotlib.use converts the
+                # backend_id to lowercase even if a module name is specified!
+                matplotlib.rcParams['backend'] = backend_id
+            else:
+                matplotlib.use(backend_id)
 
         # Import numpy as np/pyplot as plt are conventions we're trying to
         # somewhat standardize on. Making them available to users by default
         # will greatly help this.
         exec ("import numpy\n"
               "import matplotlib\n"
               "from matplotlib import pylab, mlab, pyplot\n"
               "np = numpy\n"
               "plt = pyplot\n"
               ) in self.user_ns
 
         if import_all:
             exec("from matplotlib.pylab import *\n"
                  "from numpy import *\n") in self.user_ns
 
         matplotlib.interactive(True)
 
     @classmethod
     def get_kernel(cls):
         """ Return the global kernel instance or raise a RuntimeError if it does
         not exist.
         """
         if cls._kernel is None:
             raise RuntimeError("Kernel not started!")
         else:
             return cls._kernel
 
     def start(self):
         """ Start the kernel main loop.
         """
         # Set the global kernel instance.
         Kernel._kernel = self
 
         while True:
             ident = self.reply_socket.recv()
             assert self.reply_socket.rcvmore(), "Missing message part."
             msg = self.reply_socket.recv_json()
             omsg = Message(msg)
             print>>sys.__stdout__
             print>>sys.__stdout__, omsg
             handler = self.handlers.get(omsg.msg_type, None)
             if handler is None:
                 print >> sys.__stderr__, "UNKNOWN MESSAGE TYPE:", omsg
             else:
                 handler(ident, omsg)
 
     #---------------------------------------------------------------------------
     # Kernel request handlers
     #---------------------------------------------------------------------------
 
     def execute_request(self, ident, parent):
         try:
             code = parent[u'content'][u'code']
         except:
             print>>sys.__stderr__, "Got bad msg: "
             print>>sys.__stderr__, Message(parent)
             return
         pyin_msg = self.session.msg(u'pyin',{u'code':code}, parent=parent)
         self.pub_socket.send_json(pyin_msg)
 
         # Clear the execute payload from the last request.
         self._exec_payload = {}
 
         try:
             comp_code = self.compiler(code, '<zmq-kernel>')
 
             # Replace raw_input. Note that is not sufficient to replace 
             # raw_input in the user namespace.
             raw_input = lambda prompt='': self._raw_input(prompt, ident, parent)
             __builtin__.raw_input = raw_input
 
             # Configure the display hook.
             sys.displayhook.set_parent(parent)
 
             exec comp_code in self.user_ns, self.user_ns
         except:
             result = u'error'
             etype, evalue, tb = sys.exc_info()
             tb = traceback.format_exception(etype, evalue, tb)
             exc_content = {
                 u'status' : u'error',
                 u'traceback' : tb,
                 u'ename' : unicode(etype.__name__),
                 u'evalue' : unicode(evalue)
             }
             exc_msg = self.session.msg(u'pyerr', exc_content, parent)
             self.pub_socket.send_json(exc_msg)
             reply_content = exc_content
         else:
             reply_content = { 'status' : 'ok', 'payload' : self._exec_payload }
             
         # Flush output before sending the reply.
         sys.stderr.flush()
         sys.stdout.flush()
 
         # Send the reply.
         reply_msg = self.session.msg(u'execute_reply', reply_content, parent)
         print>>sys.__stdout__, Message(reply_msg)
         self.reply_socket.send(ident, zmq.SNDMORE)
         self.reply_socket.send_json(reply_msg)
         if reply_msg['content']['status'] == u'error':
             self._abort_queue()
 
     def complete_request(self, ident, parent):
         comp = self.completer.complete(parent.content.line, parent.content.text)
         matches = {'matches' : comp, 'status' : 'ok'}
         completion_msg = self.session.send(self.reply_socket, 'complete_reply',
                                            matches, parent, ident)
         print >> sys.__stdout__, completion_msg
 
     def object_info_request(self, ident, parent):
         context = parent['content']['oname'].split('.')
         object_info = self._object_info(context)
         msg = self.session.send(self.reply_socket, 'object_info_reply',
                                 object_info, parent, ident)
         print >> sys.__stdout__, msg
 
     #---------------------------------------------------------------------------
     # Protected interface
     #---------------------------------------------------------------------------
 
     def _abort_queue(self):
         while True:
             try:
                 ident = self.reply_socket.recv(zmq.NOBLOCK)
             except zmq.ZMQError, e:
                 if e.errno == zmq.EAGAIN:
                     break
             else:
                 assert self.reply_socket.rcvmore(), "Missing message part."
                 msg = self.reply_socket.recv_json()
             print>>sys.__stdout__, "Aborting:"
             print>>sys.__stdout__, Message(msg)
             msg_type = msg['msg_type']
             reply_type = msg_type.split('_')[0] + '_reply'
             reply_msg = self.session.msg(reply_type, {'status':'aborted'}, msg)
             print>>sys.__stdout__, Message(reply_msg)
             self.reply_socket.send(ident,zmq.SNDMORE)
             self.reply_socket.send_json(reply_msg)
             # We need to wait a bit for requests to come in. This can probably
             # be set shorter for true asynchronous clients.
             time.sleep(0.1)
 
     def _raw_input(self, prompt, ident, parent):
         # Flush output before making the request.
         sys.stderr.flush()
         sys.stdout.flush()
 
         # Send the input request.
         content = dict(prompt=prompt)
         msg = self.session.msg(u'input_request', content, parent)
         self.req_socket.send_json(msg)
 
         # Await a response.
         reply = self.req_socket.recv_json()
         try:
             value = reply['content']['value']
         except:
             print>>sys.__stderr__, "Got bad raw_input reply: "
             print>>sys.__stderr__, Message(parent)
             value = ''
         return value
 
     def _object_info(self, context):
         symbol, leftover = self._symbol_from_context(context)
         if symbol is not None and not leftover:
             doc = getattr(symbol, '__doc__', '')
         else:
             doc = ''
         object_info = dict(docstring = doc)
         return object_info
 
     def _symbol_from_context(self, context):
         if not context:
             return None, context
 
         base_symbol_string = context[0]
         symbol = self.user_ns.get(base_symbol_string, None)
         if symbol is None:
             symbol = __builtin__.__dict__.get(base_symbol_string, None)
         if symbol is None:
             return None, context
 
         context = context[1:]
         for i, name in enumerate(context):
             new_symbol = getattr(symbol, name, None)
             if new_symbol is None:
                 return symbol, context[i:]
             else:
                 symbol = new_symbol
 
         return symbol, []
 
 #-----------------------------------------------------------------------------
 # Kernel main and launch functions
 #-----------------------------------------------------------------------------
 
 class ExitPollerUnix(Thread):
     """ A Unix-specific daemon thread that terminates the program immediately 
     when the parent process no longer exists.
     """
 
     def __init__(self):
         super(ExitPollerUnix, self).__init__()
         self.daemon = True
     
     def run(self):
         # We cannot use os.waitpid because it works only for child processes.
         from errno import EINTR
         while True:
             try:
                 if os.getppid() == 1:
                     os._exit(1)
                 time.sleep(1.0)
             except OSError, e:
                 if e.errno == EINTR:
                     continue
                 raise
 
 class ExitPollerWindows(Thread):
     """ A Windows-specific daemon thread that terminates the program immediately
     when a Win32 handle is signaled.
     """ 
     
     def __init__(self, handle):
         super(ExitPollerWindows, self).__init__()
         self.daemon = True
         self.handle = handle
 
     def run(self):
         from _subprocess import WaitForSingleObject, WAIT_OBJECT_0, INFINITE
         result = WaitForSingleObject(self.handle, INFINITE)
         if result == WAIT_OBJECT_0:
             os._exit(1)
 
 
 def bind_port(socket, ip, port):
     """ Binds the specified ZMQ socket. If the port is zero, a random port is
     chosen. Returns the port that was bound.
     """
     connection = 'tcp://%s' % ip
     if port <= 0:
         port = socket.bind_to_random_port(connection)
     else:
         connection += ':%i' % port
         socket.bind(connection)
     return port
 
 
 def main():
     """ Main entry point for launching a kernel.
     """
     # Parse command line arguments.
     parser = ArgumentParser()
     parser.add_argument('--ip', type=str, default='127.0.0.1',
                         help='set the kernel\'s IP address [default: local]')
     parser.add_argument('--xrep', type=int, metavar='PORT', default=0,
                         help='set the XREP channel port [default: random]')
     parser.add_argument('--pub', type=int, metavar='PORT', default=0,
                         help='set the PUB channel port [default: random]')
     parser.add_argument('--req', type=int, metavar='PORT', default=0,
                         help='set the REQ channel port [default: random]')
     if sys.platform == 'win32':
         parser.add_argument('--parent', type=int, metavar='HANDLE', 
                             default=0, help='kill this process if the process '
                             'with HANDLE dies')
     else:
         parser.add_argument('--parent', action='store_true', 
                             help='kill this process if its parent dies')
     parser.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', 'payload-svg'].")
 
     namespace = parser.parse_args()
 
     # Create a context, a session, and the kernel sockets.
     print >>sys.__stdout__, "Starting the kernel..."
     context = zmq.Context()
     session = Session(username=u'kernel')
 
     reply_socket = context.socket(zmq.XREP)
     xrep_port = bind_port(reply_socket, namespace.ip, namespace.xrep)
     print >>sys.__stdout__, "XREP Channel on port", xrep_port
 
     pub_socket = context.socket(zmq.PUB)
     pub_port = bind_port(pub_socket, namespace.ip, namespace.pub)
     print >>sys.__stdout__, "PUB Channel on port", pub_port
 
     req_socket = context.socket(zmq.XREQ)
     req_port = bind_port(req_socket, namespace.ip, namespace.req)
     print >>sys.__stdout__, "REQ Channel on port", req_port
 
     # Create the kernel.
     kernel = Kernel(session, reply_socket, pub_socket, req_socket)
 
     # Set up pylab, if necessary.
     if namespace.pylab:
         if namespace.pylab == 'auto':
             kernel.activate_pylab()
         else:
             kernel.activate_pylab(namespace.pylab)
 
     # Redirect input streams and set a display hook.
     sys.stdout = OutStream(session, pub_socket, u'stdout')
     sys.stderr = OutStream(session, pub_socket, u'stderr')
     sys.displayhook = DisplayHook(session, pub_socket)
 
     # Configure this kernel/process to die on parent termination, if necessary.
     if namespace.parent:
         if sys.platform == 'win32':
             poller = ExitPollerWindows(namespace.parent)
         else:
             poller = ExitPollerUnix()
         poller.start()
 
     # Start the kernel mainloop.
     kernel.start()
 
 
-def launch_kernel(xrep_port=0, pub_port=0, req_port=0, independent=False):
+def launch_kernel(xrep_port=0, pub_port=0, req_port=0, 
+                  pylab=False, independent=False):
     """ Launches a localhost kernel, binding to the specified ports.
 
     Parameters
     ----------
     xrep_port : int, optional
         The port to use for XREP channel.
 
     pub_port : int, optional
         The port to use for the SUB channel.
 
     req_port : int, optional
         The port to use for the REQ (raw input) channel.
 
+    pylab : bool or string, optional (default False)
+        If not False, the kernel will be launched with pylab enabled. If a
+        string is passed, matplotlib will use the specified backend. Otherwise,
+        matplotlib's default backend will be used.
+
     independent : bool, optional (default False) 
         If set, the kernel process is guaranteed to survive if this process
         dies. If not set, an effort is made to ensure that the kernel is killed
         when this process dies. Note that in this case it is still good practice
         to kill kernels manually before exiting.
 
     Returns
     -------
     A tuple of form:
         (kernel_process, xrep_port, pub_port, req_port)
     where kernel_process is a Popen object and the ports are integers.
     """
     import socket
     from subprocess import Popen
 
     # Find open ports as necessary.
     ports = []
     ports_needed = int(xrep_port <= 0) + int(pub_port <= 0) + int(req_port <= 0)
     for i in xrange(ports_needed):
         sock = socket.socket()
         sock.bind(('', 0))
         ports.append(sock)
     for i, sock in enumerate(ports):
         port = sock.getsockname()[1]
         sock.close()
         ports[i] = port
     if xrep_port <= 0:
         xrep_port = ports.pop(0)
     if pub_port <= 0:
         pub_port = ports.pop(0)
     if req_port <= 0:
         req_port = ports.pop(0)
         
-    # Spawn a kernel.
+    # Build the kernel launch command.
     command = 'from IPython.zmq.kernel import main; main()'
     arguments = [ sys.executable, '-c', command, '--xrep', str(xrep_port), 
                   '--pub', str(pub_port), '--req', str(req_port) ]
+    if pylab:
+        arguments.append('--pylab')
+        if isinstance(pylab, basestring):
+            arguments.append(pylab)
+
+    # Spawn a kernel.
     if independent:
         if sys.platform == 'win32':
             proc = Popen(['start', '/b'] + arguments, shell=True)
         else:
             proc = Popen(arguments, preexec_fn=lambda: os.setsid())
     else:
         if sys.platform == 'win32':
             from _subprocess import DuplicateHandle, GetCurrentProcess, \
                 DUPLICATE_SAME_ACCESS
             pid = GetCurrentProcess()
             handle = DuplicateHandle(pid, pid, pid, 0, 
                                      True, # Inheritable by new  processes.
                                      DUPLICATE_SAME_ACCESS)
             proc = Popen(arguments + ['--parent', str(int(handle))])
         else:
             proc = Popen(arguments + ['--parent'])
 
     return proc, xrep_port, pub_port, req_port
     
 
 if __name__ == '__main__':
     main()

IPython/zmq/kernelmanager.py

@@ -1,571 +1,575 b''
 """Base classes to manage the interaction with a running kernel.
 
 Todo
 ====
 
 * Create logger to handle debugging and console messages.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2010  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Standard library imports.
 from Queue import Queue, Empty
 from subprocess import Popen
 from threading import Thread
 import time
 
 # System library imports.
 import zmq
 from zmq import POLLIN, POLLOUT, POLLERR
 from zmq.eventloop import ioloop
 
 # Local imports.
 from IPython.utils.traitlets import HasTraits, Any, Instance, Type, TCPAddress
 from kernel import launch_kernel
 from session import Session
 
 #-----------------------------------------------------------------------------
 # Constants and exceptions
 #-----------------------------------------------------------------------------
 
 LOCALHOST = '127.0.0.1'
 
 class InvalidPortNumber(Exception):
     pass
 
 #-----------------------------------------------------------------------------
 # ZMQ Socket Channel classes
 #-----------------------------------------------------------------------------
 
 class ZmqSocketChannel(Thread):
     """The base class for the channels that use ZMQ sockets.
     """
     context = None
     session = None
     socket = None
     ioloop = None
     iostate = None
     _address = None
 
     def __init__(self, context, session, address):
         """Create a channel
 
         Parameters
         ----------
         context : :class:`zmq.Context`
             The ZMQ context to use.
         session : :class:`session.Session`
             The session to use.
         address : tuple
             Standard (ip, port) tuple that the kernel is listening on.
         """
         super(ZmqSocketChannel, self).__init__()
         self.daemon = True
 
         self.context = context
         self.session = session
         if address[1] == 0:
             message = 'The port number for a channel cannot be 0.'
             raise InvalidPortNumber(message)
         self._address = address
 
     def stop(self):
         """Stop the channel's activity.
 
         This calls :method:`Thread.join` and returns when the thread
         terminates. :class:`RuntimeError` will be raised if 
         :method:`self.start` is called again.
         """
         self.join()
 
     @property
     def address(self):
         """Get the channel's address as an (ip, port) tuple.
         
         By the default, the address is (localhost, 0), where 0 means a random
         port.
         """
         return self._address
 
     def add_io_state(self, state):
         """Add IO state to the eventloop.
 
         Parameters
         ----------
         state : zmq.POLLIN|zmq.POLLOUT|zmq.POLLERR
             The IO state flag to set.
 
         This is thread safe as it uses the thread safe IOLoop.add_callback.
         """
         def add_io_state_callback():
             if not self.iostate & state:
                 self.iostate = self.iostate | state
                 self.ioloop.update_handler(self.socket, self.iostate)
         self.ioloop.add_callback(add_io_state_callback)
 
     def drop_io_state(self, state):
         """Drop IO state from the eventloop.
 
         Parameters
         ----------
         state : zmq.POLLIN|zmq.POLLOUT|zmq.POLLERR
             The IO state flag to set.
 
         This is thread safe as it uses the thread safe IOLoop.add_callback.
         """
         def drop_io_state_callback():
             if self.iostate & state:
                 self.iostate = self.iostate & (~state)
                 self.ioloop.update_handler(self.socket, self.iostate)
         self.ioloop.add_callback(drop_io_state_callback)
 
 
 class XReqSocketChannel(ZmqSocketChannel):
     """The XREQ channel for issues request/replies to the kernel.
     """
 
     command_queue = None
 
     def __init__(self, context, session, address):
         self.command_queue = Queue()
         super(XReqSocketChannel, self).__init__(context, session, address)
 
     def run(self):
         """The thread's main activity.  Call start() instead."""
         self.socket = self.context.socket(zmq.XREQ)
         self.socket.setsockopt(zmq.IDENTITY, self.session.session)
         self.socket.connect('tcp://%s:%i' % self.address)
         self.ioloop = ioloop.IOLoop()
         self.iostate = POLLERR|POLLIN
         self.ioloop.add_handler(self.socket, self._handle_events, 
                                 self.iostate)
         self.ioloop.start()
 
     def stop(self):
         self.ioloop.stop()
         super(XReqSocketChannel, self).stop()
 
     def call_handlers(self, msg):
         """This method is called in the ioloop thread when a message arrives.
 
         Subclasses should override this method to handle incoming messages.
         It is important to remember that this method is called in the thread
         so that some logic must be done to ensure that the application leve
         handlers are called in the application thread.
         """
         raise NotImplementedError('call_handlers must be defined in a subclass.')
 
     def execute(self, code):
         """Execute code in the kernel.
 
         Parameters
         ----------
         code : str
             A string of Python code.
 
         Returns
         -------
         The msg_id of the message sent.
         """
         # Create class for content/msg creation. Related to, but possibly
         # not in Session.
         content = dict(code=code)
         msg = self.session.msg('execute_request', content)
         self._queue_request(msg)
         return msg['header']['msg_id']
 
     def complete(self, text, line, block=None):
         """Tab complete text, line, block in the kernel's namespace.
 
         Parameters
         ----------
         text : str
             The text to complete.
         line : str
             The full line of text that is the surrounding context for the 
             text to complete.
         block : str
             The full block of code in which the completion is being requested.
 
         Returns
         -------
         The msg_id of the message sent.
         """
         content = dict(text=text, line=line)
         msg = self.session.msg('complete_request', content)
         self._queue_request(msg)
         return msg['header']['msg_id']
 
     def object_info(self, oname):
         """Get metadata information about an object.
 
         Parameters
         ----------
         oname : str
             A string specifying the object name.
         
         Returns
         -------
         The msg_id of the message sent.
         """
         content = dict(oname=oname)
         msg = self.session.msg('object_info_request', content)
         self._queue_request(msg)
         return msg['header']['msg_id']
 
     def _handle_events(self, socket, events):
         if events & POLLERR:
             self._handle_err()
         if events & POLLOUT:
             self._handle_send()
         if events & POLLIN:
             self._handle_recv()
 
     def _handle_recv(self):
         msg = self.socket.recv_json()
         self.call_handlers(msg)
 
     def _handle_send(self):
         try:
             msg = self.command_queue.get(False)
         except Empty:
             pass
         else:
             self.socket.send_json(msg)
         if self.command_queue.empty():
             self.drop_io_state(POLLOUT)
 
     def _handle_err(self):
         # We don't want to let this go silently, so eventually we should log.
         raise zmq.ZMQError()
 
     def _queue_request(self, msg):
         self.command_queue.put(msg)
         self.add_io_state(POLLOUT)
 
 
 class SubSocketChannel(ZmqSocketChannel):
     """The SUB channel which listens for messages that the kernel publishes.
     """
 
     def __init__(self, context, session, address):
         super(SubSocketChannel, self).__init__(context, session, address)
 
     def run(self):
         """The thread's main activity.  Call start() instead."""
         self.socket = self.context.socket(zmq.SUB)
         self.socket.setsockopt(zmq.SUBSCRIBE,'')
         self.socket.setsockopt(zmq.IDENTITY, self.session.session)
         self.socket.connect('tcp://%s:%i' % self.address)
         self.ioloop = ioloop.IOLoop()
         self.iostate = POLLIN|POLLERR
         self.ioloop.add_handler(self.socket, self._handle_events, 
                                 self.iostate)
         self.ioloop.start()
 
     def stop(self):
         self.ioloop.stop()
         super(SubSocketChannel, self).stop()
 
     def call_handlers(self, msg):
         """This method is called in the ioloop thread when a message arrives.
 
         Subclasses should override this method to handle incoming messages.
         It is important to remember that this method is called in the thread
         so that some logic must be done to ensure that the application leve
         handlers are called in the application thread.
         """
         raise NotImplementedError('call_handlers must be defined in a subclass.')
 
     def flush(self, timeout=1.0):
         """Immediately processes all pending messages on the SUB channel.
 
         Callers should use this method to ensure that :method:`call_handlers`
         has been called for all messages that have been received on the
         0MQ SUB socket of this channel.
 
         This method is thread safe.
 
         Parameters
         ----------
         timeout : float, optional
             The maximum amount of time to spend flushing, in seconds. The
             default is one second.
         """
         # We do the IOLoop callback process twice to ensure that the IOLoop
         # gets to perform at least one full poll.
         stop_time = time.time() + timeout
         for i in xrange(2):
             self._flushed = False
             self.ioloop.add_callback(self._flush)
             while not self._flushed and time.time() < stop_time:
                 time.sleep(0.01)
 
     def _handle_events(self, socket, events):
         # Turn on and off POLLOUT depending on if we have made a request
         if events & POLLERR:
             self._handle_err()
         if events & POLLIN:
             self._handle_recv()
 
     def _handle_err(self):
         # We don't want to let this go silently, so eventually we should log.
         raise zmq.ZMQError()
 
     def _handle_recv(self):
         # Get all of the messages we can
         while True:
             try:
                 msg = self.socket.recv_json(zmq.NOBLOCK)
             except zmq.ZMQError:
                 # Check the errno?
                 # Will this trigger POLLERR?
                 break
             else:
                 self.call_handlers(msg)
 
     def _flush(self):
         """Callback for :method:`self.flush`."""
         self._flushed = True
 
 
 class RepSocketChannel(ZmqSocketChannel):
     """A reply channel to handle raw_input requests that the kernel makes."""
 
     msg_queue = None
 
     def __init__(self, context, session, address):
         self.msg_queue = Queue()
         super(RepSocketChannel, self).__init__(context, session, address)
 
     def run(self):
         """The thread's main activity.  Call start() instead."""
         self.socket = self.context.socket(zmq.XREQ)
         self.socket.setsockopt(zmq.IDENTITY, self.session.session)
         self.socket.connect('tcp://%s:%i' % self.address)
         self.ioloop = ioloop.IOLoop()
         self.iostate = POLLERR|POLLIN
         self.ioloop.add_handler(self.socket, self._handle_events, 
                                 self.iostate)
         self.ioloop.start()
 
     def stop(self):
         self.ioloop.stop()
         super(RepSocketChannel, self).stop()
 
     def call_handlers(self, msg):
         """This method is called in the ioloop thread when a message arrives.
 
         Subclasses should override this method to handle incoming messages.
         It is important to remember that this method is called in the thread
         so that some logic must be done to ensure that the application leve
         handlers are called in the application thread.
         """
         raise NotImplementedError('call_handlers must be defined in a subclass.')
 
     def input(self, string):
         """Send a string of raw input to the kernel."""
         content = dict(value=string)
         msg = self.session.msg('input_reply', content)
         self._queue_reply(msg)
 
     def _handle_events(self, socket, events):
         if events & POLLERR:
             self._handle_err()
         if events & POLLOUT:
             self._handle_send()
         if events & POLLIN:
             self._handle_recv()
 
     def _handle_recv(self):
         msg = self.socket.recv_json()
         self.call_handlers(msg)
 
     def _handle_send(self):
         try:
             msg = self.msg_queue.get(False)
         except Empty:
             pass
         else:
             self.socket.send_json(msg)
         if self.msg_queue.empty():
             self.drop_io_state(POLLOUT)
 
     def _handle_err(self):
         # We don't want to let this go silently, so eventually we should log.
         raise zmq.ZMQError()
 
     def _queue_reply(self, msg):
         self.msg_queue.put(msg)
         self.add_io_state(POLLOUT)
 
 
 #-----------------------------------------------------------------------------
 # Main kernel manager class
 #-----------------------------------------------------------------------------
 
 class KernelManager(HasTraits):
     """ Manages a kernel for a frontend.
 
     The SUB channel is for the frontend to receive messages published by the
     kernel.
         
     The REQ channel is for the frontend to make requests of the kernel.
     
     The REP channel is for the kernel to request stdin (raw_input) from the
     frontend.
     """
     # The PyZMQ Context to use for communication with the kernel.
     context = Instance(zmq.Context,(),{})
 
     # The Session to use for communication with the kernel.
     session = Instance(Session,(),{})
 
     # The kernel process with which the KernelManager is communicating.
     kernel = Instance(Popen)
 
+    # The addresses for the communication channels. 
+    xreq_address = TCPAddress((LOCALHOST, 0))
+    sub_address = TCPAddress((LOCALHOST, 0))
+    rep_address = TCPAddress((LOCALHOST, 0))
+
     # The classes to use for the various channels.
     xreq_channel_class = Type(XReqSocketChannel)
     sub_channel_class = Type(SubSocketChannel)
     rep_channel_class = Type(RepSocketChannel)
     
     # Protected traits.
-    xreq_address = TCPAddress((LOCALHOST, 0))
-    sub_address = TCPAddress((LOCALHOST, 0))
-    rep_address = TCPAddress((LOCALHOST, 0))
     _xreq_channel = Any
     _sub_channel = Any
     _rep_channel = Any
 
-    def __init__(self, **kwargs):
-        super(KernelManager, self).__init__(**kwargs)
-
     #---------------------------------  -----------------------------------------
     # Channel management methods:
     #--------------------------------------------------------------------------
 
     def start_channels(self):
         """Starts the channels for this kernel.
 
         This will create the channels if they do not exist and then start
         them. If port numbers of 0 are being used (random ports) then you
         must first call :method:`start_kernel`. If the channels have been
         stopped and you call this, :class:`RuntimeError` will be raised.
         """
         self.xreq_channel.start()
         self.sub_channel.start()
         self.rep_channel.start()
 
     def stop_channels(self):
         """Stops the channels for this kernel.
 
         This stops the channels by joining their threads. If the channels
         were not started, :class:`RuntimeError` will be raised.
         """
         self.xreq_channel.stop()
         self.sub_channel.stop()
         self.rep_channel.stop()
 
     @property
     def channels_running(self):
         """Are all of the channels created and running?"""
         return self.xreq_channel.is_alive() \
             and self.sub_channel.is_alive() \
             and self.rep_channel.is_alive()
 
     #--------------------------------------------------------------------------
     # Kernel process management methods:
     #--------------------------------------------------------------------------
 
-    def start_kernel(self):
+    def start_kernel(self, pylab=False):
         """Starts a kernel process and configures the manager to use it.
 
         If random ports (port=0) are being used, this method must be called
         before the channels are created.
+
+        Parameters:
+        -----------
+        pylab : bool or string, optional (default False)
+            See IPython.zmq.kernel.launch_kernel for documentation.
         """
         xreq, sub, rep = self.xreq_address, self.sub_address, self.rep_address
         if xreq[0] != LOCALHOST or sub[0] != LOCALHOST or rep[0] != LOCALHOST:
             raise RuntimeError("Can only launch a kernel on localhost."
                                "Make sure that the '*_address' attributes are "
                                "configured properly.")
 
         self.kernel, xrep, pub, req = launch_kernel(
-            xrep_port=xreq[1], pub_port=sub[1], req_port=rep[1])
+            xrep_port=xreq[1], pub_port=sub[1], req_port=rep[1], pylab=pylab)
         self.xreq_address = (LOCALHOST, xrep)
         self.sub_address = (LOCALHOST, pub)
         self.rep_address = (LOCALHOST, req)
 
     @property
     def has_kernel(self):
         """Returns whether a kernel process has been specified for the kernel
         manager.
         """
         return self.kernel is not None
 
     def kill_kernel(self):
         """ Kill the running kernel. """
         if self.kernel is not None:
             self.kernel.kill()
             self.kernel = None
         else:
             raise RuntimeError("Cannot kill kernel. No kernel is running!")
 
     def signal_kernel(self, signum):
         """ Sends a signal to the kernel. """
         if self.kernel is not None:
             self.kernel.send_signal(signum)
         else:
             raise RuntimeError("Cannot signal kernel. No kernel is running!")
 
     @property
     def is_alive(self):
         """Is the kernel process still running?"""
         if self.kernel is not None:
             if self.kernel.poll() is None:
                 return True
             else:
                 return False
         else:
             # We didn't start the kernel with this KernelManager so we don't
             # know if it is running. We should use a heartbeat for this case.
             return True
 
     #--------------------------------------------------------------------------
     # Channels used for communication with the kernel:
     #--------------------------------------------------------------------------
 
     @property
     def xreq_channel(self):
         """Get the REQ socket channel object to make requests of the kernel."""
         if self._xreq_channel is None:
             self._xreq_channel = self.xreq_channel_class(self.context, 
                                                          self.session,
                                                          self.xreq_address)
         return self._xreq_channel
 
     @property
     def sub_channel(self):
         """Get the SUB socket channel object."""
         if self._sub_channel is None:
             self._sub_channel = self.sub_channel_class(self.context,
                                                        self.session,
                                                        self.sub_address)
         return self._sub_channel
 
     @property
     def rep_channel(self):
         """Get the REP socket channel object to handle stdin (raw_input)."""
         if self._rep_channel is None:
             self._rep_channel = self.rep_channel_class(self.context, 
                                                        self.session,
                                                        self.rep_address)
         return self._rep_channel

IPython/zmq/pylab/backend_payload_svg.py

@@ -1,25 +1,25 b''
 # Standard library imports
 from cStringIO import StringIO
 
 # System library imports.
 from matplotlib.backends.backend_svg import new_figure_manager
 from matplotlib._pylab_helpers import Gcf
 
 # Local imports.
 from backend_payload import add_plot_payload
 
 
 def show():
     """ Deliver a SVG payload.
     """
-    figure_manager = Gcf.get_actve()
+    figure_manager = Gcf.get_active()
     if figure_manager is not None:
         data = svg_from_canvas(figure_manager.canvas)
         add_plot_payload('svg', data)
 
 def svg_from_canvas(canvas):
     """ Return a string containing the SVG representation of a FigureCanvasSvg.
     """
     string_io = StringIO()
     canvas.print_svg(string_io)
     return string_io.getvalue()