Question

我希望能够从我的python应用程序中调出一个交互式python终端。我的程序中的一些（但不是全部）变量需要暴露给解释器。

目前我使用子类和修改后的QPlainTextEdit并将所有“命令”路由到eval或exec，并跟踪dict中的单独命名空间。然而，必须有一个更优雅和健壮的方式！怎么样？

这是一个做我想要的例子，但它是用IPython和pyGTK ... http://ipython.scipy.org/moin/Cookbook/EmbeddingInGTK

以下是我目前的情况。但是有太多的角落案例我可能错过了一些。这是非常慢，尝试一个大的打印循环...它必须是一个更简单，更少漏洞的方式，...我希望!!

def runCommand(self)函数是理解我的问题的关键。理想情况下，我不想改进它，我宁愿用更简单，更聪明的东西来替换它的内容。

“main”中console.updateNamespace({'myVar1' : app, 'myVar2' : 1234})语句的功能也很重要。

import sys, os
import traceback
from PyQt4 import QtCore
from PyQt4 import QtGui

class Console(QtGui.QPlainTextEdit):
    def __init__(self, prompt='$> ', startup_message='', parent=None):
        QtGui.QPlainTextEdit.__init__(self, parent)
        self.prompt = prompt
        self.history = []
        self.namespace = {}
        self.construct = []

        self.setGeometry(50, 75, 600, 400)
        self.setWordWrapMode(QtGui.QTextOption.WrapAnywhere)
        self.setUndoRedoEnabled(False)
        self.document().setDefaultFont(QtGui.QFont("monospace", 10, QtGui.QFont.Normal))
        self.showMessage(startup_message)

    def updateNamespace(self, namespace):
        self.namespace.update(namespace)

    def showMessage(self, message):
        self.appendPlainText(message)
        self.newPrompt()

    def newPrompt(self):
        if self.construct:
            prompt = '.' * len(self.prompt)
        else:
            prompt = self.prompt
        self.appendPlainText(prompt)
        self.moveCursor(QtGui.QTextCursor.End)

    def getCommand(self):
        doc = self.document()
        curr_line = unicode(doc.findBlockByLineNumber(doc.lineCount() - 1).text())
        curr_line = curr_line.rstrip()
        curr_line = curr_line[len(self.prompt):]
        return curr_line

    def setCommand(self, command):
        if self.getCommand() == command:
            return
        self.moveCursor(QtGui.QTextCursor.End)
        self.moveCursor(QtGui.QTextCursor.StartOfLine, QtGui.QTextCursor.KeepAnchor)
        for i in range(len(self.prompt)):
            self.moveCursor(QtGui.QTextCursor.Right, QtGui.QTextCursor.KeepAnchor)
        self.textCursor().removeSelectedText()
        self.textCursor().insertText(command)
        self.moveCursor(QtGui.QTextCursor.End)

    def getConstruct(self, command):
        if self.construct:
            prev_command = self.construct[-1]
            self.construct.append(command)
            if not prev_command and not command:
                ret_val = '\n'.join(self.construct)
                self.construct = []
                return ret_val
            else:
                return ''
        else:
            if command and command[-1] == (':'):
                self.construct.append(command)
                return ''
            else:
                return command

    def getHistory(self):
        return self.history

    def setHisory(self, history):
        self.history = history

    def addToHistory(self, command):
        if command and (not self.history or self.history[-1] != command):
            self.history.append(command)
        self.history_index = len(self.history)

    def getPrevHistoryEntry(self):
        if self.history:
            self.history_index = max(0, self.history_index - 1)
            return self.history[self.history_index]
        return ''

    def getNextHistoryEntry(self):
        if self.history:
            hist_len = len(self.history)
            self.history_index = min(hist_len, self.history_index + 1)
            if self.history_index < hist_len:
                return self.history[self.history_index]
        return ''

    def getCursorPosition(self):
        return self.textCursor().columnNumber() - len(self.prompt)

    def setCursorPosition(self, position):
        self.moveCursor(QtGui.QTextCursor.StartOfLine)
        for i in range(len(self.prompt) + position):
            self.moveCursor(QtGui.QTextCursor.Right)

    def runCommand(self):
        command = self.getCommand()
        self.addToHistory(command)

        command = self.getConstruct(command)

        if command:
            tmp_stdout = sys.stdout

            class stdoutProxy():
                def __init__(self, write_func):
                    self.write_func = write_func
                    self.skip = False

                def write(self, text):
                    if not self.skip:
                        stripped_text = text.rstrip('\n')
                        self.write_func(stripped_text)
                        QtCore.QCoreApplication.processEvents()
                    self.skip = not self.skip

            sys.stdout = stdoutProxy(self.appendPlainText)
            try:
                try:
                    result = eval(command, self.namespace, self.namespace)
                    if result != None:
                        self.appendPlainText(repr(result))
                except SyntaxError:
                    exec command in self.namespace
            except SystemExit:
                self.close()
            except:
                traceback_lines = traceback.format_exc().split('\n')
                # Remove traceback mentioning this file, and a linebreak
                for i in (3,2,1,-1):
                    traceback_lines.pop(i)
                self.appendPlainText('\n'.join(traceback_lines))
            sys.stdout = tmp_stdout
        self.newPrompt()

    def keyPressEvent(self, event):
        if event.key() in (QtCore.Qt.Key_Enter, QtCore.Qt.Key_Return):
            self.runCommand()
            return
        if event.key() == QtCore.Qt.Key_Home:
            self.setCursorPosition(0)
            return
        if event.key() == QtCore.Qt.Key_PageUp:
            return
        elif event.key() in (QtCore.Qt.Key_Left, QtCore.Qt.Key_Backspace):
            if self.getCursorPosition() == 0:
                return
        elif event.key() == QtCore.Qt.Key_Up:
            self.setCommand(self.getPrevHistoryEntry())
            return
        elif event.key() == QtCore.Qt.Key_Down:
            self.setCommand(self.getNextHistoryEntry())
            return
        elif event.key() == QtCore.Qt.Key_D and event.modifiers() == QtCore.Qt.ControlModifier:
            self.close()
        super(Console, self).keyPressEvent(event)

welcome_message = '''
   ---------------------------------------------------------------
     Welcome to a primitive Python interpreter.
   ---------------------------------------------------------------
'''

if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    console = Console(startup_message=welcome_message)
    console.updateNamespace({'myVar1' : app, 'myVar2' : 1234})
    console.show();
    sys.exit(app.exec_())

Answer 1

我迟到了，但我推荐 code.InteractiveConsole 类：http://docs.python.org/py3k/library/code.html#code.InteractiveConsole

Answer 2

您可能会考虑使用线程来保持UI响应，同时打印大循环。这也有助于保持你的追溯清洁。

将变量保存在dict中是要走的路 - 这就是Python本身在内部所做的事情。至于揭露它们中的“一些但不是全部”，考虑将它们暴露出来。更容易。如果您担心安全性，请注意您无法在Python中可靠地隐藏任何内容。

对于可怕的光标/文本操作：利用您拥有GUI的事实。使用终端，您只有一个“文本框”，但在Qt中，使用日志/结果视图和单独的命令框可能更合适。

日志视图将显示输入的命令并生成只读文本框。

命令文本框允许您干净地输入命令。

这种方法用于某些Web框架 - 例如通过WebError：

enter image description here

Answer 3

支持IPython 0.13的代码更新版本的初稿

'''
Created on 18-03-2012

@author: Paweł Jarosz
'''
import os, sys
import atexit

from PySide import QtCore, QtGui

from IPython.zmq.ipkernel import IPKernelApp
from IPython.lib.kernel import find_connection_file, connect_qtconsole
from IPython.frontend.qt.kernelmanager import QtKernelManager
from IPython.frontend.qt.console.rich_ipython_widget import RichIPythonWidget
from IPython.config.application import catch_config_error

class IPythonLocalKernelApp(IPKernelApp):
    """IPython kernel application with nonblocking loop, running in dedicated thread.
    example:
        app = QtGui.QApplication([])
        kernelapp = IPythonLocalKernelApp.instance()
        kernelapp.start()
        namespace = kernelapp.get_user_namespace()
        namespace["QtGui"]=QtGui
        namespace["QtCore"]=QtCore
        app.exec_()"""
    #DEFAULT_INSTANCE_ARGS starting commandline
    DEFAULT_INSTANCE_ARGS = ['qtconsole','--pylab=inline', '--colors=linux']

    @catch_config_error
    def initialize(self, argv=None):
        super(IPythonLocalKernelApp, self).initialize(argv)
        self.kernel.eventloop = self.loop_qt4_nonblocking

    def loop_qt4_nonblocking(self, kernel):
        """Non-blocking version of the ipython qt4 kernel loop"""
        kernel.timer = QtCore.QTimer()
        kernel.timer.timeout.connect(kernel.do_one_iteration)
        kernel.timer.start(1000*kernel._poll_interval)

    def start(self, argv=DEFAULT_INSTANCE_ARGS):
        """Starts IPython kernel app
            argv: arguments passed to kernel
        """
        self.initialize(argv)
        #self.heartbeat.start()
        #if self.poller is not None:
        #    self.poller.start()

        self.kernel.start()
        super(IPythonLocalKernelApp, self).start()


    def get_connection_file(self):
        """Returne current kernel connection file."""
        return self.connection_file

    def get_user_namespace(self):
        """Returns current kernel userspace dict"""
        return self.kernel.shell.user_ns

class IPythonConsoleQtWidget(RichIPythonWidget):
    """Ipython console Qt4+ widget
        Usage example:
            app = QtGui.QApplication([])
            kernelapp = IPythonLocalKernelApp.instance()
            kernelapp.start()
            namespace = kernelapp.get_user_namespace()
            widget = IPythonConsoleQtWidget()
            widget.set_default_style(colors='linux')
            widget.connect_kernel(connection_file=kernelapp.get_connection_file())
            # if you won't to connect to remote kernel:
            widget.connect_kernel(connection_file='kernel-16098.json')

            widget.show()

            namespace["widget"] = widget
            namespace["QtGui"]=QtGui
            namespace["QtCore"]=QtCore

            app.exec_()"""
    _connection_file = None

    def __init__(self, *args, **kw):
        RichIPythonWidget.__init__(self, *args, **kw)
        self._existing = True
        self._may_close = False
        self._confirm_exit = False

    def _init_kernel_manager(self):
        km = QtKernelManager(connection_file=self._connection_file, config=self.config)
        km.load_connection_file()
        km.start_channels(hb=self._heartbeat)
        self.kernel_manager = km
        atexit.register(self.kernel_manager.cleanup_connection_file)

    def connect_kernel(self, connection_file, heartbeat=False):
        """Connect's to ipython kernel.
        connection_file    - connection file to use
        heartbeat          - should start heartbeat server? Workaround for problems with inproc embedded kernels
                             (right click save image as/save as html kills kernel heartbeat/pool(??) serwer """

        self._heartbeat = heartbeat
        if os.path.exists(connection_file):
            self._connection_file = connection_file
        else:
            self._connection_file = find_connection_file(connection_file)

        self._init_kernel_manager()



app = QtGui.QApplication([])
kernelapp = IPythonLocalKernelApp.instance()
kernelapp.start()
namespace = kernelapp.get_user_namespace()
widget = IPythonConsoleQtWidget()
widget.set_default_style(colors='linux')
widget.connect_kernel(connection_file=kernelapp.get_connection_file())
# if you won't to connect to remote kernel:
# widget.connect_kernel(connection_file='kernel-16098.json')

widget.show()

namespace["widget"] = widget
namespace["QtGui"]=QtGui
namespace["QtCore"]=QtCore

app.exec_()

Answer 4

不确定你想要什么但是试图将小部件内容保存到临时文件中并将其传递给带有Popen的标准python解释器？

Doc就在这里：http://docs.python.org/release/2.6.5/library/subprocess.html#subprocess.Popen

示例：

import tempfile, os, sys, subprocess

# get the code
code = get_widget_content()

# save the code to a temporary file
file_handle, file_path = tempfile.mkstemp()
tmp_file = os.fdopen(file_handle, 'w')
tmp_file.write(code)
tmp_file.close()

#execute it
p = subprocess.Popen([sys.executable, file_path], stdout=subprocess.PIPE, stderr=subprocess.PIPE)

# wait for the command to complete 
p.wait()

# retrieve the output:
pyerr = p.stderr.readlines()
pyout = p.stdout.readlines()

# do what ever you want with it
print(pyerr)
print(pyout)

Answer 5

听起来你做了类似于我的Veusz应用程序https://veusz.github.io/的事情。我认为您可能会发现查看更完整的实现很有用。我不能发布超链接，但看看窗口/ consolewindow.py的widget类。命令由document / commandinterpreter.py类执行。接口在document / commandinterface.py中定义。然而，它主要是操纵一个字典。

如何在PyQT小部件中嵌入Python解释器

5 个答案: