Find AWS Target Groups without any registered instances

findEmptyTargetGroups.sh

#!/bin/bash

for i in $(aws elbv2 describe-load-balancers --query 'LoadBalancers[*].LoadBalancerArn'| jq -r '.[]'); do
  tgCount=$(aws elbv2 describe-target-groups --load-balancer-arn "$i" --query 'TargetGroups[*].TargetGroupArn' | jq -r '.[]'|wc -l)
  if [ "$tgCount" -eq 0 ]; then
    echo "No TG registered on LB: $i"
  else
    for t in $(aws elbv2 describe-target-groups --load-balancer-arn "$i" --query 'TargetGroups[*].TargetGroupArn' | jq -r '.[]'); do
      instanceCount=$(aws elbv2 describe-target-health --target-group-arn "$t" --query 'TargetHealthDescriptions[*].[Target.Id,TargetHealth.State]' | jq -r '.[]' | wc -l)
      if [ "$instanceCount" -eq 0 ]; then
        echo "Empty tg: $t"
      fi
    done
  fi
done