gui/gui_classic/exchange_rate.py

   1 from PyQt4.QtCore import SIGNAL
   2 import decimal
   3 import httplib
   4 import json
   5 import threading
   6
   7 class Exchanger(threading.Thread):
   8
   9     def __init__(self, parent):
  10         threading.Thread.__init__(self)
  11         self.daemon = True
  12         self.parent = parent
  13         self.quote_currencies = None
  14         self.lock = threading.Lock()
  15         # Do price discovery
  16         self.start()
  17
  18     def exchange(self, btc_amount, quote_currency):
  19         with self.lock:
  20             if self.quote_currencies is None:
  21                 return None
  22             quote_currencies = self.quote_currencies.copy()
  23         if quote_currency not in quote_currencies:
  24             return None
  25         return btc_amount * quote_currencies[quote_currency]
  26
  27     def run(self):
  28         self.discovery()
  29
  30     def discovery(self):
  31         try:
  32             connection = httplib.HTTPConnection('blockchain.info')
  33             connection.request("GET", "/ticker")
  34         except:
  35             return
  36         response = connection.getresponse()
  37         if response.reason == httplib.responses[httplib.NOT_FOUND]:
  38             return
  39         try:
  40             response = json.loads(response.read())
  41         except:
  42             return
  43         quote_currencies = {}
  44         try:
  45             for r in response:
  46                 quote_currencies[r] = self._lookup_rate(response, r)
  47             with self.lock:
  48                 self.quote_currencies = quote_currencies
  49             self.parent.emit(SIGNAL("refresh_balance()"))
  50         except KeyError:
  51             pass
  52
  53     def get_currencies(self):
  54         return [] if self.quote_currencies == None else sorted(self.quote_currencies.keys())
  55
  56     def _lookup_rate(self, response, quote_id):
  57         return decimal.Decimal(str(response[str(quote_id)]["15m"]))
  58
  59 if __name__ == "__main__":
  60     exch = Exchanger(("BRL", "CNY", "EUR", "GBP", "RUB", "USD"))
  61     print exch.exchange(1, "EUR")
  62