plugins/qrscanner.py

   1 from electrum.util import print_error
   2 from urlparse import urlparse, parse_qs
   3 from PyQt4.QtGui import QPushButton
   4 from electrum_gui.i18n import _
   5
   6 try:
   7     import zbar
   8 except ImportError:
   9     zbar = None
  10
  11
  12
  13 def init(gui):
  14     if is_enabled():
  15         gui.set_hook('create_send_tab', create_send_tab)
  16     else:
  17         gui.unset_hook('create_send_tab', create_send_tab)
  18
  19 def get_info():
  20     return 'QR scans', "QR Scans.\nInstall the zbar package to enable this plugin"
  21
  22 def is_enabled():
  23     return is_available()
  24
  25 def toggle(gui):
  26     return is_enabled()
  27
  28
  29 def is_available():
  30     if not zbar:
  31         return False
  32
  33     try:
  34         proc = zbar.Processor()
  35         proc.init()
  36     except zbar.SystemError:
  37         # Cannot open video device
  38         return False
  39
  40     return True
  41
  42 def scan_qr():
  43     proc = zbar.Processor()
  44     proc.init()
  45     proc.visible = True
  46
  47     while True:
  48         try:
  49             proc.process_one()
  50         except:
  51             # User closed the preview window
  52             return {}
  53
  54         for r in proc.results:
  55             if str(r.type) != 'QRCODE':
  56                 continue
  57
  58             return parse_uri(r.data)
  59
  60 def parse_uri(uri):
  61     if ':' not in uri:
  62         # It's just an address (not BIP21)
  63         return {'address': uri}
  64
  65     if '//' not in uri:
  66         # Workaround for urlparse, it don't handle bitcoin: URI properly
  67         uri = uri.replace(':', '://')
  68
  69     uri = urlparse(uri)
  70     result = {'address': uri.netloc}
  71
  72     if uri.path.startswith('?'):
  73         params = parse_qs(uri.path[1:])
  74     else:
  75         params = parse_qs(uri.path)
  76
  77     for k,v in params.items():
  78         if k in ('amount', 'label', 'message'):
  79             result[k] = v[0]
  80
  81     return result
  82
  83
  84
  85 def fill_from_qr(self):
  86     qrcode = scan_qr()
  87     if 'address' in qrcode:
  88         self.payto_e.setText(qrcode['address'])
  89     if 'amount' in qrcode:
  90         self.amount_e.setText(str(qrcode['amount']))
  91     if 'label' in qrcode:
  92         self.message_e.setText(qrcode['label'])
  93     if 'message' in qrcode:
  94         self.message_e.setText("%s (%s)" % (self.message_e.text(), qrcode['message']))
  95
  96
  97 def create_send_tab(gui, grid):
  98     if is_available():
  99         b = QPushButton(_("Scan QR code"))
 100         b.clicked.connect(lambda: fill_from_qr(gui))
 101         grid.addWidget(b, 1, 5)
 102
 103
 104
 105 if __name__ == '__main__':
 106     # Run some tests
 107
 108     assert(parse_uri('1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
 109            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 110
 111     assert(parse_uri('bitcoin://1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
 112            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 113
 114     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
 115            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 116
 117     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN?amount=10') ==
 118            {'amount': '10', 'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 119
 120     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN?amount=10&label=slush&message=Small%20tip%20to%20slush') ==
 121            {'amount': '10', 'label': 'slush', 'message': 'Small tip to slush', 'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
 122
 123