echarts formatter 回调函数callback

formatter: function(params, ticket, callback) {
 pageSearch(params.data.xx).then(res => {
    self.dataCluster = res.data.data
    self.dataCluster.forEach(res=>{
     var nodeArray = []
     res.nodestatus.forEach(date=>{
       portArray += date.private + ' '
     })
     list += res.name+'<br/>' + portArray +'<br/>' + nodeArray+'<br/>';
   })
   callback(ticket, list);
})
  return 'loading'
}