add a simple Google appengine implementation

Add a really simple Google app engine implementation.

appengine.py

@@ -0,0 +1,51 @@
+from google.appengine.ext import webapp
+from google.appengine.ext.webapp.util import run_wsgi_app
+from django.utils import simplejson as json
+
+from generate_key import *
+
+class KeysHandler(webapp.RequestHandler):
+	def __init__(self):
+		self._key_matrix = read_key_file(open('master-key.txt'))
+
+	def _gen_json(self, ksv, key, is_sink):
+		return json.dumps( {
+			'ksv': ('%010x' % ksv), 
+			'key': map(lambda x: '%014x' % x, key),
+			'type': 'sink' if is_sink else 'source' },
+			sort_keys=True, indent=False)
+
+
+	def get(self, key_type, ksv_string = None):
+		self.response.headers['Content-Type'] = 'application/json'
+
+		if ksv_string is not None:
+			ksv = int(ksv_string, 16)
+		else:
+			ksv = gen_ksv()
+
+		if key_type == 'source':
+			key = gen_source_key(ksv, self._key_matrix)
+		elif key_type == 'sink':
+			key = gen_sink_key(ksv, self._key_matrix)
+		else:
+			raise RuntimeError('Unknown key type: %s' % key_type)
+
+		self.response.out.write(self._gen_json(ksv, key, True if key_type == 'sink' else False))
+
+class KsvHandler(webapp.RequestHandler):
+	def get(self):
+		self.response.headers['Content-Type'] = 'text/plain'
+		self.response.out.write('%010x' % gen_ksv())
+
+application = webapp.WSGIApplication([
+	('/keys/(sink|source)/([0-9a-f]{10})', KeysHandler),
+	('/keys/(sink|source)', KeysHandler),
+	('/keys/random_ksv', KsvHandler),
+	], debug=True)
+
+def main():
+	run_wsgi_app(application)
+
+if __name__ == "__main__":
+	main()