bug: APNs library requires parameters to be strings

closes #797

autopush/router/apns2.py

@@ -11,10 +11,15 @@
 SANDBOX = 'api.development.push.apple.com'
 SERVER = 'api.push.apple.com'
 
-APNS_PRIORITY_IMMEDIATE = 10
-APNS_PRIORITY_LOW = 5
 APNS_MAX_CONNECTIONS = 20
 
+# These values are defined by APNs as header values that should be sent.
+# The hyper library requires that all header values be strings.
+# These values should be considered "opaque" to APNs.
+# see https://developer.apple.com/search/?q=%22apns-priority%22
+APNS_PRIORITY_IMMEDIATE = '10'
+APNS_PRIORITY_LOW = '5'
+
 
 class APNSException(Exception):
     pass
@@ -101,13 +106,16 @@ def send(self, router_token, payload, apns_id,
         """
         body = json.dumps(payload)
         priority = APNS_PRIORITY_IMMEDIATE if priority else APNS_PRIORITY_LOW
+        # NOTE: Hyper requires that all header values be strings. 'Priority'
+        # is a integer string, which may be "simplified" and cause an error.
+        # The added str() function safeguards against that.
         headers = {
             'apns-id': apns_id,
-            'apns-priority': priority,
+            'apns-priority': str(priority),
             'apns-topic': topic or self.topic,
         }
         if exp:
-            headers['apns-expiration'] = exp
+            headers['apns-expiration'] = str(exp)
         url = '/3/device/' + router_token
         connection = self._get_connection()
         try:

autopush/tests/test_router.py

@@ -200,9 +200,9 @@ def test_route_low_priority_notification(self):
         ok_(self.mock_connection.request.called)
         body = self.mock_connection.request.call_args[1]
         headers = body['headers']
-        eq_(headers, {'apns-expiration': exp,
+        eq_(headers, {'apns-expiration': str(exp),
                       'apns-topic': 'com.example.SomeApp',
-                      'apns-priority': 5,
+                      'apns-priority': '5',
                       'apns-id': 'apnsid'})
 
     @inlineCallbacks