feat(placement): allow users to provide configs in placement.conf.d

Allow users to provide additional projected volumes to be mounted into
the various deployments, statefulsets, and jobs that the placement chart has
in the /etc/placement/placement.conf.d/ path. This allows for users to provide
service account or database secrets via different operators as well as
provide ways to use the chart to define common deployments while being
able to have site specific overrides.

Change-Id: I5c9e766c179e362a18832d09130d11cc1bab4944
Signed-off-by: Mathieu Gagné <mgagne@calavera.ca>

placement/templates/deployment.yaml

@@ -22,6 +22,8 @@ limitations under the License.
 
 {{- $serviceAccountName := "placement-api" }}
 {{ tuple $envAll "api" $serviceAccountName | include "helm-toolkit.snippets.kubernetes_pod_rbac_serviceaccount" }}
+
+{{- $etcSources := .Values.pod.etcSources.placement }}
 ---
 apiVersion: apps/v1
 kind: Deployment
@@ -128,6 +130,9 @@ spec:
               mountPath: /etc/placement/placement.conf
               subPath: placement.conf
               readOnly: true
+            - name: placement-etc-snippets
+              mountPath: /etc/placement/placement.conf.d/
+              readOnly: true
             - name: placement-etc
               mountPath: /etc/placement/placement-api-uwsgi.ini
               subPath: placement-api-uwsgi.ini
@@ -166,6 +171,14 @@ spec:
           secret:
             secretName: placement-etc
             defaultMode: 0444
+        - name: placement-etc-snippets
+{{- if $etcSources }}
+          projected:
+            sources:
+{{ toYaml $etcSources | indent 14 }}
+{{- else }}
+          emptyDir: {}
+{{ end }}
         {{- if .Values.conf.placement.DEFAULT.log_dir }}
         - name: log
           hostPath:

placement/values.yaml

@@ -309,6 +309,11 @@ pod:
       placement:
         volumeMounts:
         volumes:
+  # -- This allows users to add Kubernetes Projected Volumes to be mounted at /etc/placement/placement.conf.d/
+  ## This is a list of projected volume source objects for each deployment/statefulset/daemonset/cronjob
+  ## https://kubernetes.io/docs/concepts/storage/projected-volumes/
+  etcSources:
+    placement: []
   replicas:
     api: 1
   lifecycle:

releasenotes/notes/placement-a180f4e88ed81d30.yaml

@@ -0,0 +1,7 @@
+---
+placement:
+  - |
+    Allow users to add additional sources to the Projected Volume that is mounted
+    at /etc/placement/placement.conf.d/ so they may more easily override configs or provide
+    additional configs for the various services in the chart.
+...