NEZ-3146 fix：快照 markdown 不显示

nezha-fronted/src/entrance/exportHtml/App.vue

@@ -18,7 +18,7 @@
               <span>  {{dateFormat(dataJson.start * 1000)}} - {{dateFormat(dataJson.end * 1000)}} ({{dataJson.timezone}})</span>
             </div>
           </div>
-          <div v-if="!dataJson.type" id="dashboardScrollbar" class="box-content"  ref="dashboardScrollbar" style='overflow:hidden; overflow-y: auto;height: calc(100% - 72px);display: flex;flex-direction: column'>
+          <div v-if="dataJson.type === 'dashboard'" id="dashboardScrollbar" class="box-content"  ref="dashboardScrollbar" style='overflow:hidden; overflow-y: auto;height: calc(100% - 72px);display: flex;flex-direction: column'>
             <chartList
               ref="chartList"
               name="dashboard"
@@ -38,7 +38,7 @@
               :loading="chartListLoading"
             />
           </div>
-          <div v-if="dataJson.type" id="explore" class="explores" style='overflow:hidden;background: #fffffe; height: calc(100% - 72px);display: flex;flex-direction: column'>
+          <div v-if="dataJson.type == 1" id="explore" class="explores" style='overflow:hidden;background: #fffffe; height: calc(100% - 72px);display: flex;flex-direction: column'>
             <exploreItem
               ref="exploreItem"
               :key="dataJson.type"

nezha-fronted/src/entrance/exportHtml/exportHtml.js

@@ -31,13 +31,27 @@ import VueClipboard from 'vue-clipboard2'
 
 // 二次封装message 显示自动关闭进度条
 import Message from '@/components/common/message/index'
-
+// v-md-editor 预览组件
+import VMdPreview from '@kangc/v-md-editor/lib/preview'
+import githubTheme from '@kangc/v-md-editor/lib/theme/github'
+import hljs from 'highlight.js'
+import createCopyCodePlugin from '@/components/common/copy-code'
 Vue.component('element-set', elementSet) // 公用设置表头
 Vue.component('pick-time', pickTime)
 Vue.component('nzDataList', nzDataList)
 Vue.component('chartList', chartList)
 Vue.component('Pagination', Pagination) // 公用分页组件
-
+VMdPreview.xss.extend({
+  // extend white list
+  whiteList: {
+    button: ['title']
+  }
+})
+VMdPreview.use(githubTheme, {
+  Hljs: hljs
+})
+VMdPreview.use(createCopyCodePlugin())
+Vue.use(VMdPreview)
 Vue.config.productionTip = false
 Vue.use(ElementUI)
 Vue.use(Vuex)