add graceful shutdown for all api endpoints

Author: guzzijones

templates/deployments.yaml

@@ -97,6 +97,11 @@ spec:
           mountPath: /post-start.sh
           subPath: post-start.sh
         lifecycle:
+          preStop:
+            exec: # https://blog.laputa.io/graceful-shutdown-in-kubernetes-85f1c8d586da
+              # kubeproxy and kubelet both race  
+              # wait a bit to ensure kubeproxy has removed the iptables rule.
+              command: [ "sleep", {{ .Values.st2.st2auth.preStopSleep | default 10 }} ]
           postStart:
             exec:
               command: ["/bin/bash", "/post-start.sh"]
@@ -223,8 +228,10 @@ spec:
           subPath: post-start.sh
         lifecycle:
           preStop:
-            exec:
-              command: [ "sleep", {{ .Values.st2.st2api.preStopSleep }} ]
+            exec: # https://blog.laputa.io/graceful-shutdown-in-kubernetes-85f1c8d586da
+              # kubeproxy and kubelet both race  
+              # wait a bit to ensure kubeproxy has removed the iptables rule.
+              command: [ "sleep", {{ .Values.st2.st2api.preStopSleep | default 10 }} ]
           postStart:
             exec:
               command: ["/bin/bash", "/post-start.sh"]
@@ -310,6 +317,7 @@ spec:
       initContainers:
       {{- include "stackstorm-ha.init-containers-wait-for-db" . | nindent 6 }}
       {{- include "stackstorm-ha.init-containers-wait-for-mq" . | nindent 6 }}
+      terminationGracePeriodSeconds: {{ .Values.st2workflowengine.terminationGracePeriodSeconds | default 30 }}
       containers:
       - name: st2stream
         image: '{{ template "stackstorm-ha.imageRepository" . }}/st2stream:{{ tpl (.Values.st2stream.image.tag | default .Values.image.tag) . }}'
@@ -342,6 +350,11 @@ spec:
           mountPath: /post-start.sh
           subPath: post-start.sh
         lifecycle:
+          preStop:
+            exec: # https://blog.laputa.io/graceful-shutdown-in-kubernetes-85f1c8d586da
+              # kubeproxy and kubelet both race  
+              # wait a bit to ensure kubeproxy has removed the iptables rule.
+              command: [ "sleep", {{ .Values.st2.st2api.preStopSleep | default 10 }} ]
           postStart:
             exec:
               command: ["/bin/bash", "/post-start.sh"]
@@ -410,6 +423,7 @@ spec:
       {{- if .Values.image.pullSecret }}
       - name: {{ .Values.image.pullSecret }}
       {{- end }}
+      terminationGracePeriodSeconds: {{ .Values.st2api.terminationGracePeriodSeconds | default 30 }}
       containers:
       - name: st2web
         image: '{{ template "stackstorm-ha.imageRepository" . }}/st2web:{{ tpl (.Values.st2web.image.tag | default .Values.image.tag) . }}'
@@ -419,6 +433,12 @@ spec:
         {{- end }}
         ports:
         - containerPort: {{ eq (get .Values.st2web.env "ST2WEB_HTTPS" | toString) "1" | ternary 443 80 }}
+        lifecycle:
+          preStop:
+            exec: # https://blog.laputa.io/graceful-shutdown-in-kubernetes-85f1c8d586da
+              # kubeproxy and kubelet both race  
+              # wait a bit to ensure kubeproxy has removed the iptables rule.
+              command: [ "sleep", {{ .Values.st2.st2web.preStopSleep | default 10 }} ]
         # Probe to check if app is running. Failure will lead to a pod restart.
         livenessProbe:
           httpGet: