async function main(author, startPermlink, beforeDate, limit){
  let posts = []
  while(true){
    let result = await that.steem.api.getDiscussionsByAuthorBeforeDateAsync(author, startPermlink, beforeDate, limit)
    console.log(655,result)
    //做一次遍历去掉重复的文章
    result.forEach(post => {
      if (post.permlink != startPermlink) {
        posts.push(post)
      }
    })
    //取到最后一篇文章的Permlink，做为下一次查询的起始点
    startPermlink = result[result.length - 1].permlink
    //如果只能查询到一篇文章，则这是最后一篇了，可以终止查询了
    if(result.length == 1){
      console.log(888, that.posts)
      break
    }
  }
  return posts
}
let author = 'lemooljiang'
let beforeDate = new Date().toISOString().split('.')[0]
let that = this
main(author, null, beforeDate, 100)  //传入要查询的作者名，初始标签，初始时间，一次查询的条数