move upgrade logic into shell script to improve error handling

elasticsearch/examples/upgrade/Makefile

@@ -3,15 +3,9 @@ default: test
 include ../../../helpers/examples.mk
 
 RELEASE := helm-es-upgrade
-KUBE_MINOR_VERSION := $(shell kubectl version --client -o yaml | grep minor | sed 's/[^0-9]*//g')
-VERSION := $(shell test $(KUBE_MINOR_VERSION) -lt 16 && echo 7.0.0-alpha1 || echo 7.4.0)
 
 install:
-	helm repo add elastic https://helm.elastic.co && \
-	helm upgrade --wait --timeout=600 --install $(RELEASE) elastic/elasticsearch --version $(VERSION) --set clusterName=upgrade ; \
-	kubectl rollout status sts/upgrade-master --timeout=600s
-	helm upgrade --wait --timeout=600 --set terminationGracePeriod=121 --install $(RELEASE) ../../ --set clusterName=upgrade ; \
-	kubectl rollout status sts/upgrade-master --timeout=600s
+	./scripts/upgrade.sh --release $(RELEASE)
 
 init:
 	helm init --client-only

elasticsearch/examples/upgrade/scripts/upgrade.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+
+set -eo pipefail
+
+usage() {
+  cat <<-EOF
+	USAGE:
+	  $0 [--release <release-name>] [--from <elasticsearch-version>] --to <elasticsearch-version>
+	  $0 --help
+
+	OPTIONS:
+    --release <release-name>
+	    Name of the Helm release to install
+	  --from <elasticsearch-version>
+	    Elasticsearch version to use for first install
+	EOF
+  exit 1
+}
+
+RELEASE="helm-es-upgrade"
+FROM=""
+
+while [[ $# -gt 0 ]]
+do
+  key="$1"
+
+  case $key in
+    --help)
+      usage
+    ;;
+    --release)
+      RELEASE="$2"
+      shift 2
+    ;;
+    --from)
+      FROM="$2"
+      shift 2
+    ;;
+    *)
+      log "Unrecognized argument: '$key'"
+      usage
+    ;;
+  esac
+done
+
+# Elasticsearch chart < 7.4.0 are not compatible with K8S >= 1.16)
+if [[ -z $FROM ]]
+then
+  KUBE_MINOR_VERSION=$(kubectl version --client -o yaml | grep minor | sed 's/[^0-9]*//g')
+
+  if [ "$KUBE_MINOR_VERSION" -lt 16 ]
+  then
+    FROM="7.0.0-alpha1"
+  else
+    FROM="7.4.0"
+  fi
+fi
+
+helm repo add elastic https://helm.elastic.co
+
+# Initial install
+helm upgrade --wait --timeout=600 --install "$RELEASE" elastic/elasticsearch --version "$FROM" --set clusterName=upgrade -f ../docker-for-mac/values.yaml
+kubectl rollout status sts/upgrade-master --timeout=600s
+
+# Upgrade
+helm upgrade --wait --timeout=600 --set terminationGracePeriod=121 --install "$RELEASE" ../../ --set clusterName=upgrade -f ../docker-for-mac/values.yaml
+kubectl rollout status sts/upgrade-master --timeout=600s