lib/qrscanner.py

   1 from util import print_error
   2
   3 try:
   4     import zbar
   5 except ImportError:
   6     print_error("Install zbar package to enable QR scans")
   7     zbar = None
   8
   9 from urlparse import urlparse, parse_qs
  10
  11 def is_available():
  12     if not zbar:
  13         return False
  14     return True
  15
  16 def scan_qr():
  17     proc = zbar.Processor()
  18     proc.init()
  19     proc.visible = True
  20
  21     while True:
  22         try:
  23             proc.process_one()
  24         except:
  25             # User closed the preview window
  26             return {}
  27
  28         for r in proc.results:
  29             if str(r.type) != 'QRCODE':
  30                 continue
  31
  32             return parse_uri(r.data)
  33
  34 def parse_uri(uri):
  35     if ':' not in uri:
  36         # It's just an address (not BIP21)
  37         return {'address': uri}
  38
  39     if '//' not in uri:
  40         # Workaround for urlparse, it don't handle bitcoin: URI properly
  41         uri = uri.replace(':', '://')
  42
  43     uri = urlparse(uri)
  44     result = {'address': uri.netloc}
  45
  46     if uri.path.startswith('?'):
  47         params = parse_qs(uri.path[1:])
  48     else:
  49         params = parse_qs(uri.path)
  50
  51     for k,v in params.items():
  52         if k in ('amount', 'label', 'message'):
  53             result[k] = v[0]
  54
  55     return result
  56
  57 if __name__ == '__main__':
  58     # Run some tests
  59
  60     assert(parse_uri('1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
  61            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
  62
  63     assert(parse_uri('bitcoin://1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
  64            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
  65
  66     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN') ==
  67            {'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
  68
  69     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN?amount=10') ==
  70            {'amount': '10', 'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
  71
  72     assert(parse_uri('bitcoin:1Marek48fwU7mugmSe186do2QpUkBnpzSN?amount=10&label=slush&message=Small%20tip%20to%20slush') ==
  73            {'amount': '10', 'label': 'slush', 'message': 'Small tip to slush', 'address': '1Marek48fwU7mugmSe186do2QpUkBnpzSN'})
  74
  75