text: const errorPrefix = 'fpark.conf: ' ;
  const errorEnd = '\n Documentation: https://github.com/Ideolys/fpark#configuration';
  
  module.exports = function verify (config) {
  
    if (config.NODES && config.NODES.length && config.ID == null) {
      throw new Error(errorPrefix + 'ID is required' + errorEnd);
    }
  
    if (config.NODES) {
      for (let i = 0; i < config.NODES.length; i++) {
        let node = config.NODES[i];
  
        if (!node.id) {
          throw new Error(errorPrefix + 'NODES[].id is required' + errorEnd);
        }
        if (!node.host) {
          throw new Error(errorPrefix + 'NODES[].host is required, ex: "http://localhost:3000"' + errorEnd);
        }
  
        if (!node.host.startsWith('http')) {
          throw new Error(errorPrefix + 'NODES[].host should starts with "http" or "https", ex: "http://localhost:3000"' + errorEnd);
        }
      }
    }
  
  }
  