plugins/qrscanner.py

   1 from electrum.util import print_error
   2 from urlparse import urlparse, parse_qs
   3 from PyQt4.QtGui import QPushButton, QMessageBox, QDialog, QVBoxLayout, QHBoxLayout, QGridLayout, QLabel, QLineEdit, QComboBox
   4 from PyQt4.QtCore import Qt
   5
   6 from electrum.i18n import _
   7 import re
   8 import os
   9 from electrum import Transaction
  10 from electrum.bitcoin import MIN_RELAY_TX_FEE, is_valid
  11 from electrum_gui.qt.qrcodewidget import QRCodeWidget
  12 from electrum import bmp
  13 from electrum_gui.qt import HelpButton, EnterButton
  14 import json
  15
  16 try:
  17     import zbar
  18 except ImportError:
  19     zbar = None
  20
  21 from electrum import BasePlugin
  22 class Plugin(BasePlugin):
  23
  24     def fullname(self): return 'QR scans'
  25
  26     def description(self): return "QR Scans.\nInstall the zbar package to enable this plugin.\nOn linux, type: 'apt-get install python-zbar'"
  27
  28     def __init__(self, gui, name):
  29         BasePlugin.__init__(self, gui, name)
  30         self._is_available = self._init()
  31
  32     def _init(self):
  33         if not zbar:
  34             return False
  35         try:
  36             proc = zbar.Processor()
  37             proc.init(video_device=self.video_device())
  38         except zbar.SystemError:
  39             # Cannot open video device
  40             pass
  41             #return False
  42
  43         return True
  44
  45     def init(self):
  46         self.win = self.gui.main_window
  47         self.win.raw_transaction_menu.addAction(_("&From QR code"), self.read_raw_qr)
  48         b = QPushButton(_("Scan QR code"))
  49         b.clicked.connect(self.fill_from_qr)
  50         self.win.send_grid.addWidget(b, 1, 5)
  51         self.win.send_grid.setColumnStretch(5, 0)
  52         self.win.send_grid.setColumnStretch(6, 1)
  53
  54     def init_transaction_dialog(self, dialog, buttons):
  55         b = QPushButton(_("Show QR code"))
  56         b.clicked.connect(self.show_raw_qr)
  57         buttons.insertWidget(1,b)
  58
  59     def is_available(self):
  60         return self._is_available
  61
  62     def scan_qr(self):
  63         proc = zbar.Processor()
  64         try:
  65             proc.init(video_device=self.video_device())
  66         except zbar.SystemError, e:
  67             QMessageBox.warning(self.win, _('Error'), _(e), _('OK'))
  68             return
  69
  70         proc.visible = True
  71
  72         while True:
  73             try:
  74                 proc.process_one()
  75             except Exception:
  76                 # User closed the preview window
  77                 return {}
  78
  79             for r in proc.results:
  80                 if str(r.type) != 'QRCODE':
  81                     continue
  82                 return r.data
  83
  84     def show_raw_qr(self):
  85         r = self.win.read_send_tab()
  86         if not r:
  87             return
  88
  89         outputs, fee, label, coins = r
  90         try:
  91             tx = self.win.wallet.make_unsigned_transaction(outputs, fee, None, None, coins)
  92         except Exception as e:
  93             self.win.show_message(str(e))
  94             return
  95
  96         if tx.requires_fee(self.win.wallet.verifier) and fee < MIN_RELAY_TX_FEE:
  97             QMessageBox.warning(self.win, _('Error'), _("This transaction requires a higher fee, or it will not be propagated by the network."), _('OK'))
  98             return
  99
 100         try:
 101             out = {
 102             "hex" : tx.hash(),
 103             "complete" : "false"
 104             }
 105
 106             input_info = []
 107
 108         except Exception as e:
 109             self.win.show_message(str(e))
 110
 111         try:
 112             json_text = json.dumps(tx.as_dict()).replace(' ', '')
 113             self.show_tx_qrcode(json_text, 'Unsigned Transaction')
 114         except Exception as e:
 115             self.win.show_message(str(e))
 116
 117     def show_tx_qrcode(self, data, title):
 118         if not data: return
 119         d = QDialog(self.win)
 120         d.setModal(1)
 121         d.setWindowTitle(title)
 122         d.setMinimumSize(250, 525)
 123         vbox = QVBoxLayout()
 124         qrw = QRCodeWidget(data)
 125         vbox.addWidget(qrw, 0)
 126         hbox = QHBoxLayout()
 127         hbox.addStretch(1)
 128
 129         def print_qr(self):
 130             filename = "qrcode.bmp"
 131             electrum_gui.bmp.save_qrcode(qrw.qr, filename)
 132             QMessageBox.information(None, _('Message'), _("QR code saved to file") + " " + filename, _('OK'))
 133
 134         b = QPushButton(_("Save"))
 135         hbox.addWidget(b)
 136         b.clicked.connect(print_qr)
 137
 138         b = QPushButton(_("Close"))
 139         hbox.addWidget(b)
 140         b.clicked.connect(d.accept)
 141         b.setDefault(True)
 142
 143         vbox.addLayout(hbox, 1)
 144         d.setLayout(vbox)
 145         d.exec_()
 146
 147     def read_raw_qr(self):
 148         qrcode = self.scan_qr()
 149         if not qrcode:
 150             return
 151         tx = self.win.tx_from_text(qrcode)
 152         if not tx:
 153             return
 154         self.win.show_transaction(tx)
 155
 156
 157     def fill_from_qr(self):
 158         qrcode = parse_uri(self.scan_qr())
 159         if not qrcode:
 160             return
 161
 162         if 'address' in qrcode:
 163             self.win.payto_e.setText(qrcode['address'])
 164         if 'amount' in qrcode:
 165             self.win.amount_e.setText(str(qrcode['amount']))
 166         if 'label' in qrcode:
 167             self.win.message_e.setText(qrcode['label'])
 168         if 'message' in qrcode:
 169             self.win.message_e.setText("%s (%s)" % (self.win.message_e.text(), qrcode['message']))
 170
 171     def video_device(self):
 172         device = self.config.get("video_device", "default")
 173         if device == 'default':
 174             device = ''
 175         return device
 176
 177     def requires_settings(self):
 178         return True
 179
 180     def settings_widget(self, window):
 181         return EnterButton(_('Settings'), self.settings_dialog)
 182
 183     def _find_system_cameras(self):
 184         device_root = "/sys/class/video4linux"
 185         devices = {} # Name -> device
 186         if os.path.exists(device_root):
 187             for device in os.listdir(device_root):
 188                 name = open(os.path.join(device_root, device, 'name')).read()
 189                 devices[name] = os.path.join("/dev",device)
 190         return devices
 191
 192     def settings_dialog(self):
 193         system_cameras = self._find_system_cameras()
 194
 195         d = QDialog()
 196         layout = QGridLayout(d)
 197         layout.addWidget(QLabel("Choose a video device:"),0,0)
 198
 199         # Create a combo box with the available video devices:
 200         combo = QComboBox()
 201
 202         # on change trigger for video device selection, makes the
 203         # manual device selection only appear when needed:
 204         def on_change(x):
 205             combo_text = str(combo.itemText(x))
 206             combo_data = combo.itemData(x)
 207             if combo_text == "Manually specify a device":
 208                 custom_device_label.setVisible(True)
 209                 self.video_device_edit.setVisible(True)
 210                 if self.config.get("video_device") == "default":
 211                     self.video_device_edit.setText("")
 212                 else:
 213                     self.video_device_edit.setText(self.config.get("video_device"))
 214             else:
 215                 custom_device_label.setVisible(False)
 216                 self.video_device_edit.setVisible(False)
 217                 self.video_device_edit.setText(combo_data.toString())
 218
 219         # on save trigger for the video device selection window,
 220         # stores the chosen video device on close.
 221         def on_save():
 222             device = str(self.video_device_edit.text())
 223             self.config.set_key("video_device", device)
 224             d.accept()
 225
 226         custom_device_label = QLabel("Video device: ")
 227         custom_device_label.setVisible(False)
 228         layout.addWidget(custom_device_label,1,0)
 229         self.video_device_edit = QLineEdit()
 230         self.video_device_edit.setVisible(False)
 231         layout.addWidget(self.video_device_edit, 1,1,2,2)
 232         combo.currentIndexChanged.connect(on_change)
 233
 234         combo.addItem("Default","default")
 235         for camera, device in system_cameras.items():
 236             combo.addItem(camera, device)
 237         combo.addItem("Manually specify a device",self.config.get("video_device"))
 238
 239         # Populate the previously chosen device:
 240         index = combo.findData(self.config.get("video_device"))
 241         combo.setCurrentIndex(index)
 242
 243         layout.addWidget(combo,0,1)
 244
 245         self.accept = QPushButton(_("Done"))
 246         self.accept.clicked.connect(on_save)
 247         layout.addWidget(self.accept,4,2)
 248
 249         if d.exec_():
 250           return True
 251         else:
 252           return False
 253
 254
 255
 256 def parse_uri(uri):
 257     if not uri:
 258         return {}
 259
 260     if ':' not in uri:
 261         # It's just an address (not BIP21)
 262         return {'address': uri}
 263
 264     if '//' not in uri:
 265         # Workaround for urlparse, it don't handle bitcoin: URI properly
 266         uri = uri.replace(':', '://')
 267
 268     uri = urlparse(uri)
 269     result = {'address': uri.netloc}
 270
 271     if uri.query.startswith('?'):
 272         params = parse_qs(uri.query[1:])
 273     else:
 274         params = parse_qs(uri.query)
 275
 276     for k,v in params.items():
 277         if k in ('amount', 'label', 'message'):
 278             result[k] = v[0]
 279
 280     return result
 281
 282
 283
 284
 285
 286 if __name__ == '__main__':
 287     # Run some tests
 288
 289     assert(parse_uri('1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
 290            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 291
 292     assert(parse_uri('bitcoin://1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
 293            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 294
 295     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
 296            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 297
 298     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN?amount=10') ==
 299            {'amount': '10', 'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 300
 301     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN?amount=10&label=slush&message=Small%20tip%20to%20slush') ==
 302            {'amount': '10', 'label': 'slush', 'message': 'Small tip to slush', 'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 303
 304