vue获取文件hash值

import SparkMD5 from 'spark-md5';

getFileHash(file){
      return new Promise( resolve => {
        const reader = new FileReader();
        reader.readAsArrayBuffer(file);
        reader.onload = ev => {
          let buffer = ev.target.result,
              spark = new SparkMD5.ArrayBuffer(),
              HASH,
              suffix;
          spark.append(buffer);
          HASH = spark.end();
          suffix = file.name.substring(file.name.lastIndexOf(".") + 1);
          resolve({
            buffer,
            HASH,
            suffix,
            filename: `${HASH}.${suffix}`
          });
        };
      });
    },

//获取文件hash值以及后缀名
      let {
        HASH,
        suffix
      } = await this.getFileHash(file);