gui/qt/console.py

   1 # source: http://stackoverflow.com/questions/2758159/how-to-embed-a-python-interpreter-in-a-pyqt-widget
   2
   3 import sys, os, re
   4 import traceback, platform
   5 from PyQt4 import QtCore
   6 from PyQt4 import QtGui
   7 from electrum import util
   8
   9
  10 if platform.system() == 'Windows':
  11     MONOSPACE_FONT = 'Lucida Console'
  12 elif platform.system() == 'Darwin':
  13     MONOSPACE_FONT = 'Monaco'
  14 else:
  15     MONOSPACE_FONT = 'monospace'
  16
  17
  18 class Console(QtGui.QPlainTextEdit):
  19     def __init__(self, prompt='>> ', startup_message='', parent=None):
  20         QtGui.QPlainTextEdit.__init__(self, parent)
  21
  22         self.prompt = prompt
  23         self.history = []
  24         self.namespace = {}
  25         self.construct = []
  26
  27         self.setGeometry(50, 75, 600, 400)
  28         self.setWordWrapMode(QtGui.QTextOption.WrapAnywhere)
  29         self.setUndoRedoEnabled(False)
  30         self.document().setDefaultFont(QtGui.QFont(MONOSPACE_FONT, 10, QtGui.QFont.Normal))
  31         self.showMessage(startup_message)
  32
  33         self.updateNamespace({'run':self.run_script})
  34         self.set_json(False)
  35
  36     def set_json(self, b):
  37         self.is_json = b
  38
  39     def run_script(self, filename):
  40         with open(filename) as f:
  41             script = f.read()
  42
  43         # eval is generally considered bad practice. use it wisely!
  44         result = eval(script, self.namespace, self.namespace)
  45
  46
  47
  48     def updateNamespace(self, namespace):
  49         self.namespace.update(namespace)
  50
  51     def showMessage(self, message):
  52         self.appendPlainText(message)
  53         self.newPrompt()
  54
  55     def clear(self):
  56         self.setPlainText('')
  57         self.newPrompt()
  58
  59     def newPrompt(self):
  60         if self.construct:
  61             prompt = '.' * len(self.prompt)
  62         else:
  63             prompt = self.prompt
  64
  65         self.completions_pos = self.textCursor().position()
  66         self.completions_visible = False
  67
  68         self.appendPlainText(prompt)
  69         self.moveCursor(QtGui.QTextCursor.End)
  70
  71     def getCommand(self):
  72         doc = self.document()
  73         curr_line = unicode(doc.findBlockByLineNumber(doc.lineCount() - 1).text())
  74         curr_line = curr_line.rstrip()
  75         curr_line = curr_line[len(self.prompt):]
  76         return curr_line
  77
  78     def setCommand(self, command):
  79         if self.getCommand() == command:
  80             return
  81
  82         doc = self.document()
  83         curr_line = unicode(doc.findBlockByLineNumber(doc.lineCount() - 1).text())
  84         self.moveCursor(QtGui.QTextCursor.End)
  85         for i in range(len(curr_line) - len(self.prompt)):
  86             self.moveCursor(QtGui.QTextCursor.Left, QtGui.QTextCursor.KeepAnchor)
  87
  88         self.textCursor().removeSelectedText()
  89         self.textCursor().insertText(command)
  90         self.moveCursor(QtGui.QTextCursor.End)
  91
  92
  93     def show_completions(self, completions):
  94         if self.completions_visible:
  95             self.hide_completions()
  96
  97         c = self.textCursor()
  98         c.setPosition(self.completions_pos)
  99
 100         completions = map(lambda x: x.split('.')[-1], completions)
 101         t = '\n' + ' '.join(completions)
 102         if len(t) > 500:
 103             t = t[:500] + '...'
 104         c.insertText(t)
 105         self.completions_end = c.position()
 106
 107         self.moveCursor(QtGui.QTextCursor.End)
 108         self.completions_visible = True
 109
 110
 111     def hide_completions(self):
 112         if not self.completions_visible:
 113             return
 114         c = self.textCursor()
 115         c.setPosition(self.completions_pos)
 116         l = self.completions_end - self.completions_pos
 117         for x in range(l): c.deleteChar()
 118
 119         self.moveCursor(QtGui.QTextCursor.End)
 120         self.completions_visible = False
 121
 122
 123     def getConstruct(self, command):
 124         if self.construct:
 125             prev_command = self.construct[-1]
 126             self.construct.append(command)
 127             if not prev_command and not command:
 128                 ret_val = '\n'.join(self.construct)
 129                 self.construct = []
 130                 return ret_val
 131             else:
 132                 return ''
 133         else:
 134             if command and command[-1] == (':'):
 135                 self.construct.append(command)
 136                 return ''
 137             else:
 138                 return command
 139
 140     def getHistory(self):
 141         return self.history
 142
 143     def setHisory(self, history):
 144         self.history = history
 145
 146     def addToHistory(self, command):
 147         if command.find("importprivkey") > -1:
 148             return
 149
 150         if command and (not self.history or self.history[-1] != command):
 151             self.history.append(command)
 152         self.history_index = len(self.history)
 153
 154     def getPrevHistoryEntry(self):
 155         if self.history:
 156             self.history_index = max(0, self.history_index - 1)
 157             return self.history[self.history_index]
 158         return ''
 159
 160     def getNextHistoryEntry(self):
 161         if self.history:
 162             hist_len = len(self.history)
 163             self.history_index = min(hist_len, self.history_index + 1)
 164             if self.history_index < hist_len:
 165                 return self.history[self.history_index]
 166         return ''
 167
 168     def getCursorPosition(self):
 169         c = self.textCursor()
 170         return c.position() - c.block().position() - len(self.prompt)
 171
 172     def setCursorPosition(self, position):
 173         self.moveCursor(QtGui.QTextCursor.StartOfLine)
 174         for i in range(len(self.prompt) + position):
 175             self.moveCursor(QtGui.QTextCursor.Right)
 176
 177     def register_command(self, c, func):
 178         methods = { c: func}
 179         self.updateNamespace(methods)
 180
 181
 182     def runCommand(self):
 183         command = self.getCommand()
 184         self.addToHistory(command)
 185
 186         command = self.getConstruct(command)
 187
 188         if command:
 189             tmp_stdout = sys.stdout
 190
 191             class stdoutProxy():
 192                 def __init__(self, write_func):
 193                     self.write_func = write_func
 194                     self.skip = False
 195
 196                 def flush(self):
 197                     pass
 198
 199                 def write(self, text):
 200                     if not self.skip:
 201                         stripped_text = text.rstrip('\n')
 202                         self.write_func(stripped_text)
 203                         QtCore.QCoreApplication.processEvents()
 204                     self.skip = not self.skip
 205
 206             if type(self.namespace.get(command)) == type(lambda:None):
 207                 self.appendPlainText("'%s' is a function. Type '%s()' to use it in the Python console."%(command, command))
 208                 self.newPrompt()
 209                 return
 210
 211             sys.stdout = stdoutProxy(self.appendPlainText)
 212             try:
 213                 try:
 214                     # eval is generally considered bad practice. use it wisely!
 215                     result = eval(command, self.namespace, self.namespace)
 216                     if result != None:
 217                         if self.is_json:
 218                             util.print_json(result)
 219                         else:
 220                             self.appendPlainText(repr(result))
 221                 except SyntaxError:
 222                     # exec is generally considered bad practice. use it wisely!
 223                     exec command in self.namespace
 224             except SystemExit:
 225                 self.close()
 226             except Exception:
 227                 traceback_lines = traceback.format_exc().split('\n')
 228                 # Remove traceback mentioning this file, and a linebreak
 229                 for i in (3,2,1,-1):
 230                     traceback_lines.pop(i)
 231                 self.appendPlainText('\n'.join(traceback_lines))
 232             sys.stdout = tmp_stdout
 233         self.newPrompt()
 234         self.set_json(False)
 235
 236
 237     def keyPressEvent(self, event):
 238         if event.key() == QtCore.Qt.Key_Tab:
 239             self.completions()
 240             return
 241
 242         self.hide_completions()
 243
 244         if event.key() in (QtCore.Qt.Key_Enter, QtCore.Qt.Key_Return):
 245             self.runCommand()
 246             return
 247         if event.key() == QtCore.Qt.Key_Home:
 248             self.setCursorPosition(0)
 249             return
 250         if event.key() == QtCore.Qt.Key_PageUp:
 251             return
 252         elif event.key() in (QtCore.Qt.Key_Left, QtCore.Qt.Key_Backspace):
 253             if self.getCursorPosition() == 0:
 254                 return
 255         elif event.key() == QtCore.Qt.Key_Up:
 256             self.setCommand(self.getPrevHistoryEntry())
 257             return
 258         elif event.key() == QtCore.Qt.Key_Down:
 259             self.setCommand(self.getNextHistoryEntry())
 260             return
 261         elif event.key() == QtCore.Qt.Key_L and event.modifiers() == QtCore.Qt.ControlModifier:
 262             self.clear()
 263
 264         super(Console, self).keyPressEvent(event)
 265
 266
 267
 268     def completions(self):
 269         cmd = self.getCommand()
 270         lastword = re.split(' |\(|\)',cmd)[-1]
 271         beginning = cmd[0:-len(lastword)]
 272
 273         path = lastword.split('.')
 274         ns = self.namespace.keys()
 275
 276         if len(path) == 1:
 277             ns = ns
 278             prefix = ''
 279         else:
 280             obj = self.namespace.get(path[0])
 281             prefix = path[0] + '.'
 282             ns = dir(obj)
 283
 284
 285         completions = []
 286         for x in ns:
 287             if x[0] == '_':continue
 288             xx = prefix + x
 289             if xx.startswith(lastword):
 290                 completions.append(xx)
 291         completions.sort()
 292
 293         if not completions:
 294             self.hide_completions()
 295         elif len(completions) == 1:
 296             self.hide_completions()
 297             self.setCommand(beginning + completions[0])
 298         else:
 299             # find common prefix
 300             p = os.path.commonprefix(completions)
 301             if len(p)>len(lastword):
 302                 self.hide_completions()
 303                 self.setCommand(beginning + p)
 304             else:
 305                 self.show_completions(completions)
 306
 307
 308 welcome_message = '''
 309    ---------------------------------------------------------------
 310      Welcome to a primitive Python interpreter.
 311    ---------------------------------------------------------------
 312 '''
 313
 314 if __name__ == '__main__':
 315     app = QtGui.QApplication(sys.argv)
 316     console = Console(startup_message=welcome_message)
 317     console.updateNamespace({'myVar1' : app, 'myVar2' : 1234})
 318     console.show();
 319     sys.exit(app.exec_())