code: function runCmd(cmd, args, fn) {
      args = args || [];
      let runner = require('child_process').spawn(cmd, args, {
          // keep color
          stdio: 'inherit',
      });
      runner.on('close', function(code) {
          if (fn) {
              fn(code);
          }
      });
  }
docs: server.use('/api-docs', swaggerUi.serve, swaggerUi.setup(swaggerSpec)); 
  启动命令