Adding max notification constraint. (#704)

* Adds additional constraints to the max notification time. With an increasing number of certificates we need to limit the max notification time to reduce the number of certificates that need to be analyzed for notification eligibility.

lemur/tests/test_messaging.py

@@ -2,7 +2,7 @@ import pytest
 from freezegun import freeze_time
 
 from datetime import timedelta
-
+import arrow
 from moto import mock_ses
 
 
@@ -25,7 +25,14 @@ def test_needs_notification(app, certificate, notification):
 
 def test_get_certificates(app, certificate, notification):
     from lemur.notifications.messaging import get_certificates
+
+    certificate.not_after = arrow.utcnow() + timedelta(days=30)
     delta = certificate.not_after - timedelta(days=2)
+
+    notification.options = [
+        {'name': 'interval', 'value': 2}, {'name': 'unit', 'value': 'days'}
+    ]
+
     with freeze_time(delta.datetime):
         # no notification
         certs = len(get_certificates())
@@ -41,7 +48,7 @@ def test_get_certificates(app, certificate, notification):
     delta = certificate.not_after + timedelta(days=2)
     with freeze_time(delta.datetime):
         certificate.notifications.append(notification)
-        assert len(get_certificates()) == 1
+        assert len(get_certificates()) == 0
 
 
 def test_get_eligible_certificates(app, certificate, notification):