Nuxt.js: 'Window is not defined' where do I put client-side only scripts?

[7ammer]

I'm trying to run a-frame in one of my vue pages but I'm getting an error in my browser:
ReferenceError: window is not defined

I'm guessing this is because nuxt is trying to run the aframe module while rendering the page on the server.

<template>
    <div>
        <a-scene fog="type: linear; color: #FFEBDE; far:190"  debug>
            <a-entity>
                <a-collada-model src="/obj/banner.dae"></a-collada-model>
                <a-ring color="teal" radius-inner="1" radius-outer="2"></a-ring>
            </a-entity>

            <a-entity position="0 -1 10">
                <a-camera>
                    <a-cursor color="#2E3A87"></a-cursor>
                </a-camera>
            </a-entity>
            <a-entity camera="userHeight: 1.6" look-controls></a-entity>
        </a-scene>
    </div>
</template>

<script>
import 'aframe';

export default {
    mounted() {

    }
}
</script>

_{This question is available on Nuxt.js community (#c30)}

[alexchopin]

Hi,
Yes, this is exactly due to the server-side rendering.
If you need to specify that you want to import a ressource only on the client-side inside, you need to you process.browser variable.

.vue file

<script>
if (process.browser) {
  require('aframe')
}
export default {

}
</script>

nuxt.config.js

  build: {
    vendor: ['aframe']
  }

Thanks for your report, the documentation of the website will be completed soon.

[7ammer]

Ah ha, brilliant! Thanks!

[7ammer]

Hmm a-frame doesn't play nice with vue. It doesn't load properly.

[dzcpy]

I have experinced similar issues as well. I was trying to import a vue UI framework element-ui. However, it references window object and several native browser functions like addEventListener etc., so it breaks the server rendering. I'm thinking if there is any way to polyfill it somehow. Because for such kind of UI framework, if we cannot render it on server side, it doesn't quite make sense and is probably not usable for SEO purpose.

I've also treid next.js with antd ( a UI framework built on React.js which similar to element-ui ) and it worked almost perfectly ( except that next.js is using glamor as a css-in-js solution which is pretty hacky). When I have time I'll dig more for the reason why it's working in next.js but not nuxt.js.

[Atinux]

I think that every vue plugin should be able to work both client-side and server-side since the version 2.0 of Vue.js.

I asked the team behind element-ui but they said it's not their priority, but I don't think it will be complicated to make it compatible with server-side rendering, since we will only have to add if statement where a client-side only function is called.

@andyhu what library are you talking about which is working with next.js but not nuxt.js?

[dzcpy]

@Atinux I mean I'm pretty sure that antd has some window object references as well. But when I tried it, it did work with next.js. However it probably because that antd is more modular and I missed the browser specific part of the variable references. Anyway I'm going to test more.

Update: I've found that in antd it's using if (typeof window !== 'undefined') to check if it's in the browser. So as you said, it's the plugin's issue and it shouldn't directly reference window object without envirument detection. element-ui IMO is a bit buggy.

[Atinux]

I hope they will add theses check so element-ui could be used on the server-side too and render the proper HTML code!

I'm closing this issue since the question has been answer by @alexchopin by using process.BROWSER_BUILD.

[zspecza]

I know this issue is closed and all, but I just want to point out an alternate solution - Vue's lifecycle hooks. All hooks except for beforeCreate and created do not even run on the server. If you're doing any client-side manipulation or inspection and referencing built-in browser globals like window or document, then you should do those things in these hooks. This solution removes the need to inspect environment variables.

[lmj0011]

Hi,
Yes, this is exactly due to the server-side rendering.
If you need to specify that you want to import a ressource only on the client-side inside, you need to you process.BROWSER_BUILD variable.[...]

why is this still not in the docs? I followed what was there and was still having issues importing a vue plugin. this solution cleared things up

the plugin in question: https://github.com/Wanderxx/vue-fullcalendar

[alexchopin]

Documentation

[dkushner]

I have a follow up question that is a bit relevant to this issue and didn't want to clutter up the project by opening another one. I have code that needs to query browser-specific media and streaming capabilities. Where would that code best be located such that it is guaranteed to run when the component appears on the client side (whether it has previously been rendered by the server or not). I imagine this is also an issue for anyone trying to integrate with WebGL and other WebAPI technologies. Anyone have some advice?

[Atinux]

@dkushner we have a special option for JS to be run only on client-side with ssr: false option: https://nuxtjs.org/guide/plugins#client-side-only

[dkushner]

@Atinux, perfect thanks! Just happened to miss that portion of the docs.

[dkushner]

@Atinux, actually I'm sorry it looks like that documentation is explicitly for Vue plugins. Do I need to wrap every external library I use as a Vue plugin in order to leverage this? For instance THREE and SocketIO will both rely on UA-specific objects being present like document and window. So do each of these libraries then become a separate plugin?

[lmj0011]

@dkushner yep

[dotnetCarpenter]

Currently, nuxt.js 1.0.0-rc11, it is process.browser and not process.BROWSER_BUILD inside a component.

[yun-cn]

Vue-FullCalendar
app/plugins/vue-fullcalendar.js

import Vue from 'vue'

if (process.browser) {
  window.onNuxtReady(() => {
    const VueFullCalendar = require('vue-fullcalendar')
    Vue.use(VueFullCalendar)
  })
}

[MontageD]

This is the best answer I've ever seen. Thanks

[andrewharvey]

I'm closing this issue since the question has been answer by @alexchopin by using process.BROWSER_BUILD.

How would that work if we are using import instead of require? If I put my import inside the if statement I get:

NuxtServerError Module build failed: SyntaxError: 'import' and 'export' may only appear at the top level

[Atinux]

You have to use require at the moment @andrewharvey and ask for the library author to add SSR support (by giving him this link if it's a Vue.js library: https://ssr.vuejs.org/en/universal.html)

[andrewharvey]

You have to use require at the moment @andrewharvey and ask for the library author to add SSR support (by giving him this link if it's a Vue.js library: https://ssr.vuejs.org/en/universal.html)

Thanks @Atinux. I also found I can use import by moving my code out from the page into a component and use ssr: false when loading that plugin in the nuxt.config.js.

[sudhir600]

@yun313350095 I tried process.browser but it didn't work. However, process.BROWSER_BUILD is working fine for me.

But is this real solution? I mean, I have to put this if block every method, where I want to something for client-side interaction.

@andrewharvey, for i18n plugin, i did same changes like nuxt.config.js -
{ src: '~plugins/i18n.js', ssr: false },
but now i am getting error as fallbackLocale is undefined.

[mxmaxime]

Hello, I'm very confused and having really bad times :disappointed:

What if, I have to add some components after the first contentful paint ?

I've something like this:

    <no-ssr>
      <div id="post-footer">

        <post-share/>

        <div class="post-footer-suggestions" v-if="suggestionToShow">
          <p class="h2">ToRead</p>

          <post-suggestion/>

        </div>

      </div>
    </no-ssr>

But I can't figure out how to load these components in front...

// vue instance
components: {
  // What I have to do?
}

Any help would be appreciated

[sudhir600]

@EmixMaxime

<script>
import postShare from '~/components/anotherFolder/postShare.vue'

export default {
      components: {
           postShare
      }
</script>

in HTML,

<div id="post-footer">
        <postShare />
</div>

Hope this will help

[mxmaxime]

@sudhir600 Hum, that's loads the component in the server side, I have the window undefined error.

[pbastowski]

You have to lazy-import your components only when the code is running on the client, like this:

<script>
export default {
      components: {
           postShare: process.client && import('~/components/anotherFolder/postShare.vue')
      }
</script>

[somebodytolove]

Thanks @Atinux. I also found I can use import by moving my code out from the page into a component and use ssr: false when loading that plugin in the nuxt.config.js.

@andrewharvey could you provide more details or an example of this implementation using the import statement?

[ChristophAnastasiades]

The only way I found to make scripts load only on the client side is to require them in one of the hooks that are not executed on the server side.

So for example with mapbox-gl you first set a parameter mapboxgl into the data () object. Then inside your hook (for example mounted ()) you require mapbox-gl and assign it to the new parameter.

<script>
export default {
  data () {
    return {
      mapboxgl: null
    }
  },
  mounted () {
    this.maboxgl = require('mapbox-gl')
  }
}
</script>

[lock[bot]]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.