deploy google app, and then delete old versions

app.yaml

 runtime: go1.15
 env: flex
 resources:
-  cpu: 2
+  cpu: 1
   memory_gb: 1.4
   disk_size_gb: 10
 network:

deploy/delete-old-verions.sh

+#!/bin/bash
+SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
+source $SCRIPT_DIR/gcp_version.sh
+
+#wait GAE pending operations
+for ((i=1; i<120; i++)); do
+  echo "check pending GAE operations ... "
+  op=`gcloud app operations list --filter=status=PENDING --format=json`
+  if [ "$op" == "[]" ]; then 
+    echo "no pending"; 
+    del_old_instances
+    break; 
+  else
+    echo "$op"
+    echo "check $i of 120  (normally it takes 70 checks = 3-5 minutes"
+    sleep 3;
+  fi 
+done
+echo "finished";

deploy/deploy.sh

 PROJ_DIR="$SCRIPT_DIR/../"
 
 rm -rf /tmp/goweb
+echo "create /tmp/goweb"
 mkdir -p /tmp/goweb
+echo "prepare golang project"
 rsync  -a  $PROJ_DIR /tmp/goweb/
 rm -rf /tmp/goweb/html/*
-rsync -avh /mnt/hgfs/workspace/2021-07-31-BiukopWeb/ /tmp/goweb/html/
+echo "sync Web html"
+rsync -a /mnt/hgfs/workspace/2021-07-31-BiukopWeb/ /tmp/goweb/html/
 
 cd /tmp/goweb
-#gcloud app deploy
+gcloud app deploy
+
+#list all versions
+gcloud app versions list ;
+
+
 
-source $SCRIPT_DIR/gcp_version.sh
-del_old_instances

deploy/gcp_version.sh

 }
 
 del_old_instances(){
-  get_instance_id
-  echo "RUNNING VERSION: " $LAST_VERSION_ID
-
-  GCP_VERSIONS=(` gcloud app versions list | awk -F' ' '{print $2}' `)
-  LENGTH=${#GCP_VERSIONS[@]}
-  for i in $(seq 1 1 $(expr $LENGTH - 1) )
-  do
-    if [ "${GCP_VERSIONS[$i]}" != "$LAST_VERSION_ID" ] ; then
-      echo "delete old version ${GCP_VERSIONS[$i]} "
-      del_instance_by_version ${GCP_VERSIONS[$i]}
-    else
-      echo "KEEP RUNNING VERSION ${GCP_VERSIONS[$i]}"
+  VERSION_OUTPUT=$(gcloud app versions list)
+  # VERSION_OUTPUT=$` cat /home/sp/go/src/goweb/deploy/sample-version-list.txt`
+  echo "$VERSION_OUTPUT"
+  dropList=()
+
+  while IFS= read -r line; do
+    status=(` echo $line | awk -F' ' '{print $5}' `)
+    version=(` echo $line | awk -F' ' '{print $2}' `)
+    if [ "$status" == "STOPPED" ] ; then
+       dropList+=("$version")
     fi
-  done
-}
-
-del_instance_by_version() {
-  versionId=$1
-  if [ "$versionId" == "" ]; then
-    return
-  fi
-  gcloud app versions delete --service=default $versionId ;
-
-#  while true; do
-#      read -p "Do you wish to delete version $versionId ?" yn
-#      case $yn in
-#          [Yy]* )
-#            echo gcloud app instances delete $INSTANCE_ID --service=default --version=$versionId ;
-#            break;;
-#          [Nn]* ) exit;;
-#          * ) echo "Please answer yes or no.";;
-#      esac
-#  done
+  done <<< "$VERSION_OUTPUT"
 
+  #cannot do this within while, as the user input will by bypassed by <<<
+  for version in  ${dropList[@]} ; do 
+    gcloud app versions delete --service=default $version ;
+  done
 }
-

deploy/sample-version-list.txt

+SERVICE  VERSION.ID       TRAFFIC_SPLIT  LAST_DEPLOYED              SERVING_STATUS
+default  20210809t011326  0.00           2021-08-09T01:14:37+10:00  STOPPED
+default  20210809t013157  0.00           2021-08-09T01:33:04+10:00  STOPPED
+default  20210809t014534  1.00           2021-08-09T01:46:41+10:00  SERVING