Add in filtering of EBS volumes on availability-zone (#1468)

moto/ec2/models.py

@@ -1835,6 +1835,8 @@ class Volume(TaggedEC2Resource):
             return self.id
         elif filter_name == 'encrypted':
             return str(self.encrypted).lower()
+        elif filter_name == 'availability-zone':
+            return self.zone.name
         else:
             return super(Volume, self).get_filter_value(
                 filter_name, 'DescribeVolumes')

tests/test_ec2/test_elastic_block_store.py

@@ -186,6 +186,11 @@ def test_volume_filters():
         {volume1.id, volume3.id, volume4.id}
     )
 
+    volumes_by_availability_zone = conn.get_all_volumes(filters={'availability-zone': 'us-east-1b'})
+    set([vol.id for vol in volumes_by_availability_zone if vol.id in volume_ids]).should.equal(
+        {volume2.id}
+    )
+
 
 @mock_ec2_deprecated
 def test_volume_attach_and_detach():