bash waiters curl, netcat, wget, cassandra

bash waiters

while [[ "200" != "$(curl -v -s -o /dev/null -w '%{http_code}' ${url})" ]]; do
  sleep 10
done


function wait_wget() {
  local url=$1
  
  while true; do
    if wget "${url}"; then
      echo "${url} is avaliable"
      break;
    else
      echo "waiting for ${url} to become available..."
      sleep 10
    fi
  done;
}

function wait_nc() {
  local host=$1
  local port=$2

  while true; do
    if nc -zvw 1 ${host} ${port}; then
      echo "tcp ${host}:${port} is available"
      break;
    else
      echo "waiting for tcp ${host}:${port} ..."
      sleep 10
    fi
  done;
}


function wait_cassandra(){
  local host=$1
  local port=$2

  while true; do
    if cqlsh ${host} ${port} -e 'describe keyspaces;'; then
      echo "tcp ${host}:${port} is available"
      break;
    else
      echo "waiting for tcp ${host}:${port} ..."
      sleep 10
    fi
  done;
}