Failed to mount component: template or render function not defined?

Question

I am creating website using node.js, express, pug, vue.js. I have one problem regarding Vue.js

app.js

window.Vue = require('vue');
Vue.component('work-list', require('../views/components/WorkList.vue'));

const app = new Vue({
  el: '#app',
  data: {
    message: 'Welcome'
  }
});

WorkList.vue

<script>
  export default {
    name: 'WorkList',
    data: function () {
      return {
        message: 'WorkList Page'
      }
    }
  }
</script>

index.pug

(HTML Code..)
body
    #app.container
        h1 {{ message}}
        .row
            block content
        a(href="/worklist") Go to worklist
  script(src="bundle.js")

worklist.pug

extends index.pug

block content
work-list {{ message }}

When I try to access worklist page, browser is returning following error message.

How can I make WorkList in Root element?

Answer 1

This might also occur even when a <template></template> is defined in your Vue single file component. In addition to require('/path/to/your/Component.vue') as the second parameter to Vue.component() when registering the component globally in your app.js, you also have to specify .default :

Vue.component('work-list', require('../views/components/WorkList.vue').default);
                                                                      ^^^^^^^^

Answer 2

Your component file 'WorkList.vue' needs a template defined. The most straight forward way to construct a '.vue' component is with three sections.

<template>
   //template code goes here.
</template>

<script>
   // vue javascript here
</script>

<style>
   // applicable styles here
</style>

Your component is expecting the <template> markup.

There are other ways to define the template as well. https://v2.vuejs.org/v2/guide/render-function.html

When defining your component

Vue.component('my-component', {
    template: `<div> markup here</div>`,
    data(){
      ...
    }
});

X-Templates (similar to above)

Vue.component('my-component', {
    template: `#someElementId`,
    ....

 //then in a separate component.js file

 <script type="text/x-template" id="someElementId">
   <div> markup here </div>
</script>

Using the render function

export default {
    data() {
     ...
    }
    render(createElement) {
        return createElement(
            'div', {....}
        ....
 

Answer 3

Following on from Erich's answer , if you are using ES6 imports it would be:

import WorkList from '../views/components/WorkList'; // .vue is extension not required

Vue.component('work-list', WorkList);

Answer 4

In my case, I forgot to put my dynamic import inside an arrow function.

Wrong:

{
    path: "/example/",
    component: import("@/pages/Example"),
}

Correct:

{
    path: "/example/",
    component: () => import("@/pages/Example"),
}

Answer 5

I believe the problem is the alias for vue in your webpack config.

Check out the different types of Vue builds .

Try using vue.min.js or vue.common.js

//webpack.config.js
...
alias: {
  'vue$': 'vue/dist/vue.common.js'
},
...