Issue 121: Supplying init containers within helm charts (#148)

* Adds support for initContainers and prestartCommand within the schema registry helm charts

Signed-off-by: SrishT <[email protected]>

Author: SrishT

charts/schema-registry/Chart.yaml

@@ -12,6 +12,6 @@ apiVersion: v2
 name: schema-registry
 description: Schema Registry Helm chart for Kubernetes
 type: application
-version: 0.0.1
-appVersion: 0.0.1
+version: 0.1.0
+appVersion: 0.1.0
 home: https://github.com/pravega/schema-registry

charts/schema-registry/README.md

@@ -49,14 +49,16 @@ The following table lists the configurable parameters of the schema registry cha
 | Parameter | Description | Default |
 | ----- | ----------- | ------ |
 | `replicas` | Number of replicas | `2` |
-| `image.repository` | Repository for schema registry image | `pravega/schema-registry` |
-| `image.tag` | Tag for schema registry image | `0.0.1` |
+| `image.repository` | Repository for schema registry image | `pravega/schemaregistry` |
+| `image.tag` | Tag for schema registry image | `0.1.0` |
 | `image.pullPolicy` | Pull policy for schema registry image | `IfNotPresent` |
 | `serviceAccount.create` | Whether to create a service account | `true` |
 | `serviceAccount.name` | Name of the service account | `schema-registry` |
 | `serviceAccount.annotations` | Annotations to be added to the service account | |
 | `service.type` | Schema registry service type | `LoadBalancer` |
 | `service.port` | Schema registry service port | `9092` |
+| `initContainer` | Configuration for the init container | `{}` |
+| `container` | Additional configuration for the schema registry container, to be provided if an init container has been configured | `{}` |
 | `ingress.enabled` | Whether to expose as an ingress resource | `false` |
 | `ingress.path` | Path for the ingress | `/` |
 | `ingress.annotations` | Annotations for the ingress | `{}` |

charts/schema-registry/templates/configmap.yaml

@@ -41,3 +41,8 @@ data:
   "TLS_KEY_FILE": "/etc/secret-volume/{{ .Values.tls.keyFile }}"
   "TLS_KEY_PASSWORD_FILE": "/etc/secret-volume/{{ .Values.tls.keyPasswordFile }}"
   {{- end }}
+  {{- if and .Values.container .Values.container.command }}
+  "PRE_START_CMD": "{{ .Values.container.command }}"
+  {{- else }}
+  "PRE_START_CMD": ""
+  {{- end }}

charts/schema-registry/templates/deployment.yaml

@@ -46,7 +46,7 @@ spec:
                 - sh
                 - -c
                 - netstat -ltn 2> /dev/null | grep {{ .Values.service.port }} || ss -ltn 2> /dev/null | grep {{ .Values.service.port }}
-          {{- if or .Values.authentication.enabled .Values.tls.enabled }}
+          {{- if or .Values.authentication.enabled .Values.tls.enabled (and .Values.container .Values.container.volume) }}
           volumeMounts:
           {{- if .Values.authentication.enabled }}
           - name: auth-passwd-secret
@@ -58,8 +58,29 @@ spec:
             mountPath: /etc/secret-volume
             readOnly: true
           {{- end }}
+          {{- if and .Values.container .Values.container.volume }}
+          - name: transfer-data
+            mountPath: {{ .Values.container.volume.mountPath }}
           {{- end }}
-      {{- if or .Values.authentication.enabled .Values.tls.enabled }}
+          {{- end }}
+      {{- if .Values.initContainer }}
+      initContainers:
+        - name: {{ .Values.initContainer.name }}
+          image: "{{ .Values.initContainer.image.repository }}:{{ .Values.initContainer.image.tag }}"
+          imagePullPolicy: {{ .Values.initContainer.image.pullPolicy }}
+          command:
+{{ toYaml .Values.initContainer.command | indent 12 }}
+          {{- if .Values.initContainer.resources }}
+          resources:
+{{ toYaml .Values.initContainer.command | indent 12 }}
+          {{- end }}
+          {{- if .Values.initContainer.volume }}
+          volumeMounts:
+          - name: transfer-data
+            mountPath: {{ .Values.initContainer.volume.mountPath }}
+          {{- end }}
+      {{- end }}
+      {{- if or .Values.authentication.enabled .Values.tls.enabled (and .Values.initContainer .Values.initContainer.volume) }}
       volumes:
       {{- if .Values.authentication.enabled }}
       - name: auth-passwd-secret
@@ -71,4 +92,8 @@ spec:
         secret:
           secretName: {{ .Values.tls.secret }}
       {{- end }}
+      {{- if and .Values.container .Values.container.volume }}
+      - name: transfer-data
+        emptyDir: {}
+      {{- end }}
       {{- end }}

charts/schema-registry/values.yaml

@@ -15,8 +15,8 @@
 replicas: 2
 
 image:
-  repository: pravega/schema-registry
-  tag: 0.0.1
+  repository: pravega/schemaregistry
+  tag: 0.1.0
   pullPolicy: IfNotPresent
 
 ## Service account name and whether to create it.
@@ -29,6 +29,26 @@ service:
   type: LoadBalancer
   port: 9092
 
+initContainer: {}
+  # name: ""
+  # image:
+  #   repository:
+  #   tag:
+  #   pullPolicy: IfNotPresent
+  ## provide a list containing the command that needs to be executed within the init container
+  ## e.g. ["/bin/sh", "-c", "cp /data/* /target"]
+  # command: []
+  # resources: {}
+  # volume:
+  #   mountPath: /target
+
+container: {}
+  ## just provide the command to be executed within the entrypoint
+  ## e.g. "cp /additional_libs/* /opt/schema-registry/lib/"
+  # command: ""
+  # volume:
+  #   mountPath: /additional_libs
+
 ## Ingress configuration.
 ingress:
   enabled: false

docker/pravega-schema-registry/scripts/entrypoint.sh

@@ -21,4 +21,8 @@ if [ ${WAIT_FOR} ];then
     ${SCRIPTS_DIR}/wait_for
 fi
 
+if [[ -n "$PRE_START_CMD" ]];then
+    $PRE_START_CMD
+fi
+
 exec /opt/schema-registry/bin/schema-registry