#!/bin/sh
# ここでは environment と role というメタデータがあると仮定

environment=$1
role=$2

if [ -z "$role" ]; then
  echo "[usage] $0 environment role"
  exit 1
fi

gcloud compute instances list --format json |
  jq -r "map(select(.metadata.items)) |
         map(select(.metadata.items | from_entries | .environment == \"${environment}\" and .role == \"${role}\")) |
         .[].name"