feat: add cache-control header to 410's (#773)

Our 410's should result in the sender no longer sending, but senders
ignore this. To avoid excessive re-processing on repeats, 410's now
include a Cache-Control header set to the max of 1 day for nginx to
cache results.

Closes #770

autopush/tests/test_integration.py

@@ -11,7 +11,9 @@
 import uuid
 from contextlib import contextmanager
 from StringIO import StringIO
+from httplib import HTTPResponse  # noqa
 from unittest.case import SkipTest
+
 from zope.interface import implementer
 
 import boto
@@ -22,6 +24,7 @@
 from autobahn.twisted.websocket import WebSocketServerFactory
 from jose import jws
 from nose.tools import eq_, ok_
+from typing import Optional  # noqa
 from twisted.internet import reactor
 from twisted.internet.defer import inlineCallbacks, returnValue, Deferred
 from twisted.internet.endpoints import SSL4ServerEndpoint, TCP4ServerEndpoint
@@ -136,6 +139,7 @@ def __init__(self, url, use_webpush=False, sslcontext=None):
         self.use_webpush = use_webpush
         self.channels = {}
         self.messages = {}
+        self.notif_response = None  # type: Optional[HTTPResponse]
         self._crypto_key = """\
 keyid="http://example.org/bob/keys/123;salt="XZwpw6o37R-6qoZjw6KwAw"\
 """
@@ -276,6 +280,7 @@ def send_notification(self, channel=None, version=None, data=None,
         log.debug("%s Response (%s): %s", method, resp.status, resp.read())
         http.close()
         eq_(resp.status, status)
+        self.notif_response = resp
         location = resp.getheader("Location", None)
         log.debug("Response Headers: %s", resp.getheaders())
         if self.use_webpush:
@@ -1028,7 +1033,7 @@ def test_multiple_delivery_with_multiple_ack(self):
     @inlineCallbacks
     def test_no_delivery_to_unregistered(self):
         data = str(uuid.uuid4())
-        client = yield self.quick_register(use_webpush=True)
+        client = yield self.quick_register(use_webpush=True)  # type: Client
         ok_(client.channels)
         chan = client.channels.keys()[0]
 
@@ -1039,6 +1044,10 @@ def test_no_delivery_to_unregistered(self):
 
         yield client.unregister(chan)
         result = yield client.send_notification(data=data, status=410)
+
+        # Verify cache-control
+        eq_(client.notif_response.getheader("Cache-Control"), "max-age=86400")
+
         eq_(result, None)
         yield self.shut_down(client)
 

autopush/web/base.py

@@ -184,6 +184,11 @@ def _write_response(self, status_code, errno, message=None, error=None,
         if headers:
             for header in headers.keys():
                 self.set_header(header, headers.get(header))
+
+        # 410's get the max-age cache control header
+        if status_code == 410:
+            self.set_header("Cache-Control", "max-age=86400")
+
         self._track_timing()
         self.finish()
 
@@ -195,6 +200,7 @@ def _validation_err(self, fail):
                       status_code=exc.status_code,
                       errno=exc.errno,
                       client_info=self._client_info)
+
         self._write_response(exc.status_code, exc.errno,
                              message="Request did not validate %s" %
                                      (exc.message or ""),