diff --git a/ansible/roles/nova-cell/filter_plugins/filters.py b/ansible/roles/nova-cell/filter_plugins/filters.py
index 95f2f07cffedf9174199377b2a52e19183615995..48c9ce8f3f4df374d33717e695b9614ceaf81f51 100644
--- a/ansible/roles/nova-cell/filter_plugins/filters.py
+++ b/ansible/roles/nova-cell/filter_plugins/filters.py
@@ -1,5 +1,7 @@
 #!/usr/bin/python
 
+# Copyright (c) 2019 StackHPC Ltd.
+#
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
@@ -12,82 +14,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from jinja2.exceptions import TemplateRuntimeError
-import re
+from kolla_ansible import nova_filters as filters
 
 
 class FilterModule(object):
-    def filters(self):
-        return {
-            'extract_cell': self._extract_cell,
-            'namespace_haproxy_for_cell': self._namespace_haproxy_for_cell,
-        }
-
-    def _extract_cell(self, list_cells_cli_output, cell_name):
-        """Extract cell settings from nova_manage CLI
-
-        This filter tries to extract the cell settings for the specified cell
-        from the output of the command:
-        nova-manage cell_v2 list_cells --verbose
-        If the cell is not registered, nothing is returned.
-
-        An example line from this command for a cell with no name looks like this:
-
-        |  | 68a3f49e-27ec-422f-9e2e-2a4e5dc8291b | rabbit://openstack:password@1.2.3.4:5672 | mysql+pymysql://nova:password@1.2.3.4:3306/nova |  False   |  # noqa
-
-        And for a cell with a name:
+    """Nova cell filters."""
 
-        | cell1 | 68a3f49e-27ec-422f-9e2e-2a4e5dc8291b | rabbit://openstack:password@1.2.3.4:5672 | mysql+pymysql://nova:password@1.2.3.4:3306/nova |  False   |  # noqa
-
-        """
-        # NOTE(priteau): regexp doesn't support passwords containing spaces
-        p = re.compile(
-            r'\| +(?P<cell_name>[^ ]+)? +'
-            r'\| +(?!00000000-0000-0000-0000-000000000000)'
-            r'(?P<cell_uuid>[0-9a-f\-]+) +'
-            r'\| +(?P<cell_message_queue>[^ ]+) +'
-            r'\| +(?P<cell_database>[^ ]+) +'
-            r'\| +(?P<cell_disabled>[^ ]+) +'
-            r'\|$')
-        cells = []
-        for line in list_cells_cli_output['stdout_lines']:
-            match = p.match(line)
-            if match:
-                # If there is no cell name, we get None in the cell_name match
-                # group. Use an empty string to match the default cell.
-                match_cell_name = match.group('cell_name') or ""
-                if match_cell_name == cell_name:
-                    cells.append(match.groupdict())
-        if len(cells) > 1:
-            raise TemplateRuntimeError(
-                "Cell: {} has duplicates. "
-                "Manual cleanup required.".format(cell_name))
-        return cells[0] if cells else None
-
-    def _namespace_haproxy_for_cell(self, services, cell_name):
-        """Add namespacing to HAProxy configuration for a cell.
-
-        :param services: dict defining service configuration.
-        :param cell_name: name of the cell, or empty if cell has no name.
-        :returns: the services dict, with haproxy configuration modified to
-            provide namespacing between cells.
-        """
-
-        def _namespace(name):
-            # Backwards compatibility - no cell name suffix for cells without a
-            # name.
-            return "{}_{}".format(name, cell_name) if cell_name else name
-
-        # Service name must be namespaced as haproxy-config uses this as the
-        # config file name.
-        services = {
-            _namespace(service_name): service
-            for service_name, service in services.items()
-        }
-        for service in services.values():
-            if service.get('haproxy'):
-                service['haproxy'] = {
-                    _namespace(name): service['haproxy'][name]
-                    for name in service['haproxy']
-                }
-        return services
+    def filters(self):
+        return filters.get_filters()
diff --git a/kolla_ansible/nova_filters.py b/kolla_ansible/nova_filters.py
new file mode 100644
index 0000000000000000000000000000000000000000..fc2be76f4587eba12ed3eb7403e5d762b8b4c5c4
--- /dev/null
+++ b/kolla_ansible/nova_filters.py
@@ -0,0 +1,93 @@
+# Copyright (c) 2019 StackHPC Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import jinja2
+import re
+
+
+def extract_cell(list_cells_cli_output, cell_name):
+    """Extract cell settings from nova_manage CLI
+
+    This filter tries to extract the cell settings for the specified cell
+    from the output of the command:
+    nova-manage cell_v2 list_cells --verbose
+    If the cell is not registered, nothing is returned.
+
+    An example line from this command for a cell with no name looks like this:
+
+    |  | 68a3f49e-27ec-422f-9e2e-2a4e5dc8291b | rabbit://openstack:password@1.2.3.4:5672 | mysql+pymysql://nova:password@1.2.3.4:3306/nova |  False   |  # noqa
+
+    And for a cell with a name:
+
+    | cell1 | 68a3f49e-27ec-422f-9e2e-2a4e5dc8291b | rabbit://openstack:password@1.2.3.4:5672 | mysql+pymysql://nova:password@1.2.3.4:3306/nova |  False   |  # noqa
+
+    """
+    # NOTE(priteau): regexp doesn't support passwords containing spaces
+    p = re.compile(
+        r'\| +(?P<cell_name>[^ ]+)? +'
+        r'\| +(?!00000000-0000-0000-0000-000000000000)'
+        r'(?P<cell_uuid>[0-9a-f\-]+) +'
+        r'\| +(?P<cell_message_queue>[^ ]+) +'
+        r'\| +(?P<cell_database>[^ ]+) +'
+        r'\| +(?P<cell_disabled>[^ ]+) +'
+        r'\|$')
+    cells = []
+    for line in list_cells_cli_output['stdout_lines']:
+        match = p.match(line)
+        if match:
+            # If there is no cell name, we get None in the cell_name match
+            # group. Use an empty string to match the default cell.
+            match_cell_name = match.group('cell_name') or ""
+            if match_cell_name == cell_name:
+                cells.append(match.groupdict())
+    if len(cells) > 1:
+        raise jinja2.TemplateRuntimeError(
+            "Cell: {} has duplicates. "
+            "Manual cleanup required.".format(cell_name))
+    return cells[0] if cells else None
+
+
+def namespace_haproxy_for_cell(services, cell_name):
+    """Add namespacing to HAProxy configuration for a cell.
+
+    :param services: dict defining service configuration.
+    :param cell_name: name of the cell, or empty if cell has no name.
+    :returns: the services dict, with haproxy configuration modified to
+            provide namespacing between cells.
+    """
+    def _namespace(name):
+        # Backwards compatibility - no cell name suffix for cells without a
+        # name.
+        return "{}_{}".format(name, cell_name) if cell_name else name
+
+    # Service name must be namespaced as haproxy-config uses this as the
+    # config file name.
+    services = {
+        _namespace(service_name): service
+        for service_name, service in services.items()
+    }
+    for service in services.values():
+        if service.get('haproxy'):
+            service['haproxy'] = {
+                _namespace(name): service['haproxy'][name]
+                for name in service['haproxy']
+            }
+    return services
+
+
+def get_filters():
+    return {
+        "extract_cell": extract_cell,
+        "namespace_haproxy_for_cell": namespace_haproxy_for_cell,
+    }
diff --git a/kolla_ansible/tests/unit/data/nova_manage_cli_output_duplicate_cells b/kolla_ansible/tests/unit/data/nova_manage_cli_output_duplicate_cells
new file mode 100644
index 0000000000000000000000000000000000000000..dde0899cb955af3748fd343a00774d9fabb8cd0e
--- /dev/null
+++ b/kolla_ansible/tests/unit/data/nova_manage_cli_output_duplicate_cells
@@ -0,0 +1,7 @@
++----------+--------------------------------------+----------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------+----------+
+|   Name   |                 UUID                 |                                        Transport URL                                         |                                       Database Connection                                       | Disabled |
++----------+--------------------------------------+----------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------+----------+
+|  cell0   | 00000000-0000-0000-0000-000000000000 |                                           none:///                                           |   mysql+pymysql://nova:gTEDJEJU24ZXJjhhEt6Xu4nP3fnvPAoQ5oOb8OnS@172.28.128.253:3306/nova_cell0  |  False   |
+| cell0001 | 5af50f3f-82ed-47b2-9de8-7dd4eafa7648 | rabbit://openstack:0flZc3qqwczsisbaT94uCcArVNXEJnhhj4JAAAMI@172.28.128.32:5673/nova_cell0001 | mysql+pymysql://nova:mpyerUgpbQeXjaDV1nhsVDLWjsFSoCss6dHCXK7G@172.28.128.252:3305/nova_cell0001 |  False   |
+| cell0001 | 5af50f3f-82ed-47b2-9de8-7dd4eafa7648 | rabbit://openstack:0flZc3qqwczsisbaT94uCcArVNXEJnhhj4JAAAMI@172.28.128.32:5673/nova_cell0001 | mysql+pymysql://nova:mpyerUgpbQeXjaDV1nhsVDLWjsFSoCss6dHCXK7G@172.28.128.252:3305/nova_cell0001 |  False   |
++----------+--------------------------------------+----------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------+----------+
diff --git a/kolla_ansible/tests/unit/data/nova_manage_cli_output_multiple_cells b/kolla_ansible/tests/unit/data/nova_manage_cli_output_multiple_cells
new file mode 100644
index 0000000000000000000000000000000000000000..061399a0673c2917489734919e64f288bdbd6840
--- /dev/null
+++ b/kolla_ansible/tests/unit/data/nova_manage_cli_output_multiple_cells
@@ -0,0 +1,8 @@
++----------+--------------------------------------+----------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------+----------+
+|   Name   |                 UUID                 |                                        Transport URL                                         |                                       Database Connection                                       | Disabled |
++----------+--------------------------------------+----------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------+----------+
+|  cell0   | 00000000-0000-0000-0000-000000000000 |                                           none:///                                           |   mysql+pymysql://nova:gTEDJEJU24ZXJjhhEt6Xu4nP3fnvPAoQ5oOb8OnS@172.28.128.253:3306/nova_cell0  |  False   |
+|          | 68a3f49e-27ec-422f-9e2e-2a4e5dc8291b | rabbit://openstack:94uCcArVNXEJnhhj4JAAAMI432h5j3k2bb3bbjkB@172.28.128.30:5672               | mysql+pymysql://nova:1nhsVDLWjsFSoCsda453bJBsdsbjkabf77sadsdD@172.28.128.252:3305/nova          |  False   |
+| cell0001 | 5af50f3f-82ed-47b2-9de8-7dd4eafa7648 | rabbit://openstack:0flZc3qqwczsisbaT94uCcArVNXEJnhhj4JAAAMI@172.28.128.32:5673/nova_cell0001 | mysql+pymysql://nova:mpyerUgpbQeXjaDV1nhsVDLWjsFSoCss6dHCXK7G@172.28.128.252:3305/nova_cell0001 |  False   |
+| cell0002 | 087697bb-bfc2-471d-befb-0c0fcc7630e4 | rabbit://openstack:d9LaCxGrQX9Lla9aMZcS7fQ5xLH8S5HwHFrl6jdJ@172.28.128.31:5672/nova_cell0002 | mysql+pymysql://nova:Dj3f3l4yv2SuhbsJyv3ahGIwUMa9TKchw6EXtQfp@172.28.128.253:3306/nova_cell0002 |  True    |
++----------+--------------------------------------+----------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------+----------+
diff --git a/kolla_ansible/tests/unit/test_nova_filters.py b/kolla_ansible/tests/unit/test_nova_filters.py
new file mode 100644
index 0000000000000000000000000000000000000000..128ee67c57139ec936ec5454cbbd3a29390c725c
--- /dev/null
+++ b/kolla_ansible/tests/unit/test_nova_filters.py
@@ -0,0 +1,189 @@
+# Copyright (c) 2019 StackHPC Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import unittest
+
+import jinja2
+import os
+
+from kolla_ansible import nova_filters as filters
+
+
+class TestFilters(unittest.TestCase):
+
+    def _test_extract_cell(self, test_data, cell_name):
+        nova_manage_output = {}
+        with open(test_data, 'r') as f:
+            nova_manage_output['stdout_lines'] = f.readlines()
+        return filters.extract_cell(nova_manage_output, cell_name)
+
+    def test_extract_with_no_name(self):
+        test_data = os.path.join(os.path.dirname(
+            __file__), 'data', 'nova_manage_cli_output_multiple_cells')
+        actual = self._test_extract_cell(test_data, '')
+        expected = {'cell_name': None,
+                    'cell_uuid': '68a3f49e-27ec-422f-9e2e-2a4e5dc8291b',
+                    'cell_message_queue': 'rabbit://openstack:94uCcArVNXEJnhhj4JAAAMI432h5j3k2bb3bbjkB@172.28.128.30:5672',  # noqa
+                    'cell_database': 'mysql+pymysql://nova:1nhsVDLWjsFSoCsda453bJBsdsbjkabf77sadsdD@172.28.128.252:3305/nova',  # noqa
+                    'cell_disabled': 'False'}
+        self.assertDictEqual(expected, actual)
+
+    def test_extract_cell0001(self):
+        test_data = os.path.join(os.path.dirname(
+            __file__), 'data', 'nova_manage_cli_output_multiple_cells')
+        actual = self._test_extract_cell(test_data, 'cell0001')
+        expected = {'cell_name': 'cell0001',
+                    'cell_uuid': '5af50f3f-82ed-47b2-9de8-7dd4eafa7648',
+                    'cell_message_queue': 'rabbit://openstack:0flZc3qqwczsisbaT94uCcArVNXEJnhhj4JAAAMI@172.28.128.32:5673/nova_cell0001',  # noqa
+                    'cell_database': 'mysql+pymysql://nova:mpyerUgpbQeXjaDV1nhsVDLWjsFSoCss6dHCXK7G@172.28.128.252:3305/nova_cell0001',  # noqa
+                    'cell_disabled': 'False'}
+        self.assertDictEqual(expected, actual)
+
+    def test_extract_cell0002(self):
+        test_data = os.path.join(os.path.dirname(
+            __file__), 'data', 'nova_manage_cli_output_multiple_cells')
+        actual = self._test_extract_cell(test_data, 'cell0002')
+        expected = {'cell_name': 'cell0002',
+                    'cell_uuid': '087697bb-bfc2-471d-befb-0c0fcc7630e4',
+                    'cell_message_queue': 'rabbit://openstack:d9LaCxGrQX9Lla9aMZcS7fQ5xLH8S5HwHFrl6jdJ@172.28.128.31:5672/nova_cell0002',  # noqa
+                    'cell_database': 'mysql+pymysql://nova:Dj3f3l4yv2SuhbsJyv3ahGIwUMa9TKchw6EXtQfp@172.28.128.253:3306/nova_cell0002',  # noqa
+                    'cell_disabled': 'True'}
+        self.assertDictEqual(expected, actual)
+
+    def test_extract_missing_cell(self):
+        test_data = os.path.join(os.path.dirname(
+            __file__), 'data', 'nova_manage_cli_output_multiple_cells')
+        actual = self._test_extract_cell(test_data, 'cell0003')
+        self.assertIsNone(actual)
+
+    def test_extract_duplicate_cell(self):
+        test_data = os.path.join(os.path.dirname(
+            __file__), 'data', 'nova_manage_cli_output_duplicate_cells')
+        self.assertRaisesRegexp(jinja2.TemplateRuntimeError, 'duplicates',
+                                self._test_extract_cell, test_data, 'cell0001')
+
+    def test_namespace_haproxy_for_cell_with_empty_name(self):
+        example_services = {
+            'nova-novncproxy': {
+                'group': 'some_group',
+                'enabled': True,
+                'haproxy': {
+                    'nova_novncproxy': {
+                        'enabled': True,
+                        'mode': 'http',
+                        'external': False,
+                        'port': '1232',
+                        'listen_port': '1233',
+                        'backend_http_extra': ['timeout tunnel 1h'],
+                    },
+                    'nova_novncproxy_external': {
+                        'enabled': True,
+                        'mode': 'http',
+                        'external': True,
+                        'port': '1234',
+                        'listen_port': '1235',
+                        'backend_http_extra': ['timeout tunnel 1h'],
+                    }
+                }
+            }
+        }
+        actual = filters.namespace_haproxy_for_cell(example_services, '')
+        # No change
+        self.assertDictEqual(example_services, actual)
+
+    def test_namespace_haproxy_for_cell_with_single_proxy(self):
+        example_services = {
+            'nova-novncproxy': {
+                'group': 'some_group',
+                'enabled': True,
+                'haproxy': {
+                    'nova_novncproxy': {
+                        'enabled': True,
+                        'mode': 'http',
+                        'external': False,
+                        'port': '1232',
+                        'listen_port': '1233',
+                        'backend_http_extra': ['timeout tunnel 1h'],
+                    },
+                    'nova_novncproxy_external': {
+                        'enabled': True,
+                        'mode': 'http',
+                        'external': True,
+                        'port': '1234',
+                        'listen_port': '1235',
+                        'backend_http_extra': ['timeout tunnel 1h'],
+                    }
+                }
+            }
+        }
+        actual = filters.namespace_haproxy_for_cell(
+            example_services, 'cell0001')
+        expected = {
+            'nova-novncproxy_cell0001': {
+                'group': 'some_group',
+                'enabled': True,
+                'haproxy': {
+                    'nova_novncproxy_cell0001': {
+                        'enabled': True,
+                        'mode': 'http',
+                        'external': False,
+                        'port': '1232',
+                        'listen_port': '1233',
+                        'backend_http_extra': ['timeout tunnel 1h'],
+                    },
+                    'nova_novncproxy_external_cell0001': {
+                        'enabled': True,
+                        'mode': 'http',
+                        'external': True,
+                        'port': '1234',
+                        'listen_port': '1235',
+                        'backend_http_extra': ['timeout tunnel 1h'],
+                    }
+                }
+            }
+        }
+        self.assertDictEqual(expected, actual)
+
+    def test_namespace_haproxy_for_cell_with_multiple_proxies(self):
+        example_services = {
+            'nova-novncproxy': {
+                'haproxy': {
+                    'nova_novncproxy': {},
+                    'nova_novncproxy_external': {}
+                }
+            },
+            'nova-spicehtml5proxy': {
+                'haproxy': {
+                    'nova_spicehtml5proxy': {},
+                    'nova_spicehtml5proxy_external': {}
+                }
+            }
+        }
+        actual = filters.namespace_haproxy_for_cell(
+            example_services, 'cell0002')
+        expected = {
+            'nova-novncproxy_cell0002': {
+                'haproxy': {
+                    'nova_novncproxy_cell0002': {},
+                    'nova_novncproxy_external_cell0002': {}
+                }
+            },
+            'nova-spicehtml5proxy_cell0002': {
+                'haproxy': {
+                    'nova_spicehtml5proxy_cell0002': {},
+                    'nova_spicehtml5proxy_external_cell0002': {}
+                }
+            }
+        }
+        self.assertDictEqual(expected, actual)