Parameterize sidecar image name for Kubernetes scripts. (#117)

Author: davidbtucker

kube/README.md

@@ -10,6 +10,10 @@ Required environment variables:
 * `GCP_PROJECT`: GCP project parameter for the sidecar
 * `SIDECAR_IMAGE_TAG`: Version parameter for the sidecar
 
+Optional environment variables:
+* `SIDECAR_IMAGE_NAME`: Image name parameter for the sidecar (default:
+  gcr.io/stackdriver-prometheus/stackdriver-prometheus-sidecar)
+
 If your cluster is not the default context:
 
 ```sh

kube/patch.sh

@@ -12,13 +12,16 @@ if [  $# -le 1 ]; then
   exit 1
 fi
 
+# Override to use a different Docker image name for the sidecar.
+export SIDECAR_IMAGE_NAME=${SIDECAR_IMAGE_NAME:-'gcr.io/stackdriver-prometheus/stackdriver-prometheus-sidecar'}
+
 kubectl -n "${KUBE_NAMESPACE}" patch "$1" "$2" --type strategic --patch "
 spec:
   template:
     spec:
       containers:
       - name: sidecar
-        image: gcr.io/stackdriver-prometheus/stackdriver-prometheus-sidecar:${SIDECAR_IMAGE_TAG}
+        image: ${SIDECAR_IMAGE_NAME}:${SIDECAR_IMAGE_TAG}
         imagePullPolicy: Always
         args:
         - \"--stackdriver.project-id=${GCP_PROJECT}\"