node后台生成echarts图表

//2，生成图片数据
    var option = {
      tooltip: {
        trigger: 'item',
        formatter: "{a} <br/>{b} : {c} ({d}%)"
      },

      series: [{
        name: '访问来源',
        type: 'pie',
        radius: '55%',
        center: ['50%', '60%'],
        data: [
          { value: 335, name: '直接访问' },
          { value: 310, name: '邮件营销' },
          { value: 234, name: '联盟广告' },
          { value: 135, name: '视频广告' },
          { value: 1548, name: '搜索引擎' }
        ],
        itemStyle: {
          emphasis: {
            shadowBlur: 10,
            shadowOffsetX: 0,
            shadowColor: 'rgba(0, 0, 0, 0.5)'
          }
        }
      }]
    };
　　//模块引入
    var node_echarts = require('node-echarts');
    var path = require('path');

    node_echarts({
       500, // Image width, type is number. 
      height: 500, // Image height, type is number. 
      option: option, // Echarts configuration, type is Object.
      //If the path  is not set, return the Buffer of image. 
      path: path.join(__dirname, '../data/image1.png'), // Path is filepath of the image which will be created.
      enableAutoDispose: true //Enable auto-dispose echarts after the image is created.
    })