plugins/qrscanner.py

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