getPosts(author, startPermlink, limit, posts) {
  let that = this
  return new Promise((resolve, reject) => {
    let beforeDate = new Date().toISOString().split('.')[0]
    that.steem.api.getDiscussionsByAuthorBeforeDate(author, startPermlink, beforeDate, limit, function (err, result) {
      //做一次遍历去掉重复的文章
      result.forEach(post => {
        if (post.permlink != startPermlink) {
          that.newposts.push(post)
        }
      })
      resolve(result)
    })
  })
}

//mounted函数中
let _this = this
async function main(author, startPermlink, limit, posts){
  while(true){
    let result = await _this.getPosts(author, startPermlink, limit, posts)
    //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, _this.newposts)
      break
    }
  }
}
let author = 'lemooljiang'
main(author, null, 5, []) //传入要查询的作者名，初始标签，一次查询的条数，初始化数组