Use jinja2.pass_context instead of contextfilter

The contextfilter decorator was deprecated in jinja2 3.0.0, and has been
dropped in 3.1.0. This results in the following warning, and failed
attempts to use filters:

    [WARNING]: Skipping plugin (filters.py) as it seems to be invalid:
    module 'jinja2' has no attribute 'contextfilter'

This change switches to use the pass_context decorator. The minimum
version of Jinja2 is raised to 3 to ensure pass_context is present.

This backport has been updated to also support Jinja2 2.x releases,
since the Wallaby upper constraints specify 2.11.3. In practice, most
users will not use UC to install kolla-ansible.

Change-Id: I649dd6211d3ae72b9539bc44652ef8cf5d579777
(cherry picked from commit fc2292b230)

kolla_ansible/filters.py

@@ -12,13 +12,17 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-import jinja2
+# NOTE: jinja2 3.1.0 dropped contextfilter in favour of pass_context.
+try:
+    from jinja2 import pass_context
+except ImportError:
+    from jinja2 import contextfilter as pass_context
 
 from kolla_ansible import exception
 from kolla_ansible.helpers import _call_bool_filter
 
 
-@jinja2.contextfilter
+@pass_context
 def service_enabled(context, service):
     """Return whether a service is enabled.
 
@@ -34,7 +38,7 @@ def service_enabled(context, service):
     return _call_bool_filter(context, enabled)
 
 
-@jinja2.contextfilter
+@pass_context
 def service_mapped_to_host(context, service):
     """Return whether a service is mapped to this host.
 
@@ -62,7 +66,7 @@ def service_mapped_to_host(context, service):
         service.get("container_name", "<unknown>"))
 
 
-@jinja2.contextfilter
+@pass_context
 def service_enabled_and_mapped_to_host(context, service):
     """Return whether a service is enabled and mapped to this host.
 
@@ -74,7 +78,7 @@ def service_enabled_and_mapped_to_host(context, service):
             service_mapped_to_host(context, service))
 
 
-@jinja2.contextfilter
+@pass_context
 def select_services_enabled_and_mapped_to_host(context, services):
     """Select services that are enabled and mapped to this host.
 

kolla_ansible/kolla_address.py

@@ -14,14 +14,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from jinja2.filters import contextfilter
+# NOTE: jinja2 3.1.0 dropped contextfilter in favour of pass_context.
+try:
+    from jinja2 import pass_context
+except ImportError:
+    from jinja2 import contextfilter as pass_context
 from jinja2.runtime import Undefined
 
 from kolla_ansible.exception import FilterError
 from kolla_ansible.helpers import _call_bool_filter
 
 
-@contextfilter
+@pass_context
 def kolla_address(context, network_name, hostname=None):
     """returns IP address on the requested network
 

releasenotes/notes/jinja2-pass-context-2afc328ade8c407b.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Fixes an issue seen when using Jinja2 3.1.0.