fix(devtools): refactor local run script

scripts/start.sh

 #!/bin/bash
 
+set -eo pipefail
+
+KUBE_PROXY=${KUBE_PROXY:-}
+KUBE_PROXY_PORT=${KUBE_PROXY_PORT:-8001}
+MANAGER_PORT=${MANAGER_PORT:-8080}
+
+RESOURCIFIER=bin/resourcifier
+EXPANDYBIRD=bin/expandybird
+MANAGER=bin/manager
+
+error_exit() {
+  # Display error message and exit
+  echo "error: ${1:-"unknown error"}" 1>&2
+  exit 1
+}
+
+require_binary_exists() {
+  if ! command -v "$1" >/dev/null 2>&1; then
+    error_exit "Cannot find binary for $1. Build binaries by running 'make build'"
+  fi
+}
+
+for b in $RESOURCIFIER $EXPANDYBIRD $MANAGER; do
+  require_binary_exists $b
+
+  # kill if currently running
+  pkill -f $b
+done
+
 LOGDIR=log
 if [[ ! -d $LOGDIR ]]; then
   mkdir $LOGDIR
 fi
 
-KUBECTL=`which kubectl`
-if [[ -z $KUBECTL ]] ; then
-  echo Cannot find kubectl
-  exit 1
-fi
+KUBECTL=$(which kubectl) || error_exit "Cannot find kubectl"
 
 echo "Starting resourcifier..."
-RESOURCIFIER=bin/resourcifier
-if [[ -z $RESOURCIFIER ]] ; then
-	echo Cannot find resourcifier
-	exit 1
-fi
-pkill -f $RESOURCIFIER
-nohup $RESOURCIFIER > $LOGDIR/resourcifier.log 2>&1 --kubectl=$KUBECTL --port=8082 &
-echo
+nohup $RESOURCIFIER > $LOGDIR/resourcifier.log 2>&1 --kubectl="${KUBECTL}" --port=8082 &
 
 echo "Starting expandybird..."
-EXPANDYBIRD=bin/expandybird
-if [[ -z $EXPANDYBIRD ]] ; then
-  echo Cannot find expandybird
-  exit 1
-fi
-pkill -f $EXPANDYBIRD
 nohup $EXPANDYBIRD > $LOGDIR/expandybird.log 2>&1 --port=8081 --expansion_binary=expansion/expansion.py &
-echo
 
 echo "Starting deployment manager..."
-MANAGER=bin/manager
-if [[ -z $MANAGER ]] ; then
-  echo Cannot find manager
-  exit 1
+nohup $MANAGER > $LOGDIR/manager.log 2>&1 --port="${MANAGER_PORT}"  --kubectl="${KUBECTL}" --expanderURL=http://localhost:8081 --deployerURL=http://localhost:8082 &
+
+if [[ "$KUBE_PROXY" ]]; then
+  echo "Starting kubectl proxy..."
+  pkill -f "$KUBECTL proxy"
+  nohup "$KUBECTL" proxy --port="${KUBE_PROXY_PORT}" &
+  sleep 1s
 fi
-pkill -f $MANAGER
-nohup $MANAGER > $LOGDIR/manager.log 2>&1 --port=8080  --kubectl=$KUBECTL --expanderURL=http://localhost:8081 --deployerURL=http://localhost:8082 &
-echo
 
-echo "Starting kubectl proxy..."
-pkill -f "$KUBECTL proxy"
-nohup $KUBECTL proxy --port=8001 &
-sleep 1s
-echo
+cat <<EOF
+Local manager server is now running on :${MANAGER_PORT}
+
+Logging to ${LOGDIR}
+
+To use helm:
+
+  export HELM_HOST=http://localhost:${MANAGER_PORT}
+  ./bin/helm list
+
+To deploy example guestbook:
+
+     ./bin/dm -service=http://localhost:8088 deploy examples/guestbook/guestbook.yaml
 
-echo "Done."
+EOF