text: const grpc = require('@grpc/grpc-js');
  const protoLoader = require('@grpc/proto-loader');
  // const protobuf = require('google-protobuf/google/protobuf');
  
  var packageDefinition = protoLoader.loadSync(__dirname + "/protos/mail_template.proto", {
      keepCase: true,
      longs: String,
      enums: String,
      defaults: true,
      oneofs: true
  });
  
  var mail = grpc.loadPackageDefinition(packageDefinition).mail;
  
  function main() {
      const client = new mail.Mail('localhost:50051', grpc.credentials.createInsecure());
      
      const payload = {
          name : "ddochea",
          date : new Date().toUTCString()
      }
      client.RegistMailTemplate({
          name : "name", 
          mailbody : "hello {name}! \r\nnice to meet you.\r\n date : {date}", 
          payload
      }, function (err, res) {
          console.log("client:", res);
      });
  }
  
  main();