I am using Nuxt.js / Vuejs for my app, and I keep facing this error in different places:
The client-side rendered virtual DOM tree is not matching server-rendered content.
This is likely caused by incorrect HTML markup, for example nesting block-level elements inside <p>, or missing <tbody>.
Bailing hydration and performing full client-side render.
I would like to understand what is the best way to debug this error? Is their a way I can record/get the virtual DOM tree for client and server so I could compare and find where the error lies?
Mine is a large application and manually verifying is difficult.
Partial answer: with Chrome DevTools, you can localize the issue and see exactly what element caused the issue. Do the following (I did that with Nuxt 5.6.0 and Chrome 64.0.3282.186)
Show DevTools in Chrome (F12)
Load the page that causes "the client-side rendered virtual DOM tree..." warning.
Scroll to the warning in DevTools console.
Click at the source location hyperlink of the warning (in my case it was vue.runtime.esm.js:574).
Set a breakpoint there (left-clicking at line number in the source code browser).
Make the same warning to appear again. I'm not saying it is always possible, but in my case I simply reloaded the page. If there are many warnings, you can check the message by moving a mouse over msg variable.
When you found your message and stopped on a breakpoint, look at the call stack. Click one frame down to call to "patch" to open its source. Hover mouse over hydrate function call 4 lines above the execution line in patch. Hyperlink to the source of hydrate would open.
In the hydrate function, move about 15 lines from the start and set a breakpoint where false is returned after assertNodeMatch returned false. Set the breakpoint there and remove all other breakpoints.
Make the same warning to happen again. Now, when breakpoint is hit, execution should stop in the hydrate function. Switch to DevTools console and evaluate elm and then vnode. Here elm seem to be a server-rendered DOM element while vnode is a virtual DOM node. Elm is printed as HTML so you can figure out where the error happened.
For me this error happened cuz get Array list in AsyncData and rendered <tr> tags by v-for, i put v-for codes in <client-only> blocks and problem solved
This error can be really painfull to debug. In order to quickly get the element causing an issue edit node_modules/vue/dist/vue.esm.js and add the following lines :
// Search for this line:
function hydrate (elm, vnode, insertedVnodeQueue, inVPre) {
var i;
var tag = vnode.tag;
var data = vnode.data;
var children = vnode.children;
inVPre = inVPre || (data && data.pre);
vnode.elm = elm;
// Add the following lines:
console.log('elm', elm)
console.log('vnode', vnode)
console.log('inVpre', inVPre)
// ...
You will get in the console the failing node.
There are a lot of ways of fixing this issue, but most of them are not actual fixes, just hacky band-aids. To note a few:
wrap it into <client-only> tags, beware of some important details tho
using a v-show instead of a v-if
trying to hack some lifecycles
etc...
I highly recommend reading this gorgeous article written by Alexander Lichter
https://blog.lichter.io/posts/vue-hydration-error/
He'll explain you that you should diagnose why this happens and fix the actual issue.
Basically each time something is different from what was generated on the server and what is available when done hydrating on the client will cause this error.
Some of which are:
invalid HTML (having a block element inside of a <p>, same goes for an a tag nested into another, etc...)
3rd party scripts messing around with your components
different state on server vs client
any random is risky (new Date() for example)
any page related to authentication
I highly recommend reading the article to understand in Alexandre's own words how to handle this kind of issue. If you're in a hurry you could always use one band-aid fix but try to actually fix the issue for the best performance and to keep the code clean.
I had the same issue as of nuxt version 2.14.0 while implementing vue-particles package. The fix was to surround the tags with no-ssr and it fixed the issue.
EDIT:
Updated variant of the solution (if Nuxt version is above 2.9.0)
<client-only>
<vue-particles>
</vue-particles>
</client-only>
Old solution:
<no-ssr>
<vue-particles>
</vue-particles>
</no-ssr>
Thanks to budden73's answer, I did a little improvement on the debug process.
Open dev tool
click on the warn message, and click on the first line of the warn message, you will be directed to the Sources panel, with a file name vue.runtime.esm.js?xxxx
ctrl+f to search the above file for assertNodeMatch, not the function, but like:
if (process.env.NODE_ENV !== 'production') {
if (!assertNodeMatch(elm, vnode, inVPre)) {
return false
}
}
Add a break point at the line return false
Refresh the page, and the breakpoint will be triggered.
At the right side of the Sources panel, Under Scope->Local, click on the elm element, you will be directed back to the Elements panel.
The above element is the client side rendered element, compare with your code to see the difference.
If you can't find the source of the bug, the brutal way to fix it is using nuxt's <client-only> tag.
Another likely brutal way is described here. Add an isHydrate variable which default is false, set to true in mounted hook, and render the element after the variable set to true.
For Nuxt version above 2.10 it doesn't need to install nothing, just use the default component <client-only> as mentioned https://nuxtjs.org/api/components-client-only/.
Check the previous warning:
In "nuxt": "^2.12.2", You can spot the cause easily from the previous warning.
In my case:
Incorrect
<nuxt-link to="/game42day">
<a>Game For Today</a>
</nuxt-link>
Correct:
<nuxt-link to="/game42day">
Game For Today
</nuxt-link>
If you're rendering a component conditionally with v-if, then you have two options to solve the problem:
The first one is wrapping the element in <no-ssr></no-ssr> tag.
The second approach is replacing v-if with v-show, here is the link to Vue docs.
Turns out, in my case, I had HTML comment tags , which was causing this stupid, annoying error. Took me too long to figure it out but in case it helps someone.
In my case I had to change this:
<v-expansion-panel-header v-text="name" />
to this:
<v-expansion-panel-header>{{ name }}</v-expansion-panel-header>
I also get many errors due to this problem. I list two cases I often encounter, hope can help you.
With vuetify button, when you create a common component, you should use: <v-btn>{{text}}</v-btn>. Example:
<template>
<v-btn
:width="width"
:color="color"
:class="[rounded ? 'rounded-pill' : 'rounded-lg',textColor]"
v-on:click="onClick"
elevation="0"
:outlined="outlined"
:type="type"
:name="name"
:form="form"
:disabled="disabled"
v-bind="$attrs"
>{{ text }}</v-btn>
</template>
Don't use v-html with <p> tag.
Not use: <p v-html='html'></p>.
Use: <div v-html='html'></div>.
Besides, if you use <client-only></client-only>, this problem is definitely solved, but if you need to SEO page or show google ads, it is not good solution.
Ok this is going to sound silly. I tried a bunch of different solutions for about 15 mins such as restarting the server and deleting the .nuxt directory but I was too lazy to use #budden73's big brain solution. What ended up working for me was simply restarting my computer, give it a shot.
What I have found so far from observation is that when you are using third party packages like jQuery (specially), they sometimes inject html tags into the dom. So Vue/Nuxt looses track of the dom tree and starts complaining.
I was having the same problem and after a while I removed all jQuery and replaced jQuery functionality with Vuejs and those error were all gone.
See here for an example of how to deal with integrations (e.g. Google Analytics or FB Pixel) that modify the DOM. Basically create a plugin and exclude from SSR.
https://nuxtjs.org/faq/ga
What about:
extend (config, ctx) {
config.resolve.symlinks = false
}
See this [Vue warn]: The client-side rendered virtual DOM tree is not matching server-rendered content ( Nuxt / Vue / lerna monorepo )
Now that you found the code causing the problem, the first thing you should do is to verify that your markup (possibly coming from an API) is valid. Code like <p><p>Text</p></p> is not valid because a p element doesn’t allow other block elements (like a paragraph tag) inside.
Be aware, that tags are not allowed to have block level elements like <div> or <p> as children. These <span> tags are used default tag for Vue’s transitions though. You can change that though via <Transition tag="div">.
Check if have used any block-level element inside the inline element.
for example: inside , inside
If you have used an HTML table make sure you have used the tag
In my case, I changed my codes from
<p v-html="$md.render(post.content)"></p>
to
<p>{{ $md.render(post.content) }}</p>
In my case this problem was caused by markdownit module, I solved it by changing the html markup used with v-html. I was with <p> at the beginning and I ended with <div>.
I have some <p> in my v-html render (with $md.render()) so take care if you have same problems with different markups.
Is it possible to parse string with components inside to template in vue.js? Example of string:
"Some text, some <b>bold text</b>, and inserted image from this
component <vue-simple-image :src='images/my_image_name.png' />, another text and html tags."
It looks like I need store such strings to database to use them later for recreating user input from vue-wysiwyg editor.
In the strict sense you asked the question, I do not think this is possible. There is a v-html directive, that can render html for you but not components. This is also considered an anti-pattern, as the vue guide states:
Dynamically rendering arbitrary HTML on your website can be very dangerous because it can easily lead to XSS attacks. Only use v-html on trusted content and never on user-provided content.
You could look into dynamic components in order to render vue components based on user input.
You could parse the wysiwyg user input, split the string on recognized vue-component tags (so you have an array of pieces of elements with sequences of regular html and elements that are single vue-components), and then use a template with v-for looping to render this. (non-working pseudocode) example:
<div id="renderedWysiwygInput">
<div v-for="elem in splitInput">
<component v-if="stringIsVueComponent(element)" v-bind:is="element"></component>
<div v-else v-html="element"></div>
</div>
</div>
You'll have to work this example out a bit more though to account for the possibility of input inside the vue components themselves, for example if you are filling slots. I would try to limit what kind of input you are going to support to keep it manageable.
No, this is not possible, because Vue component is not just an html piece, it is a js class. So you need to register it properly and so on...
I am suing https://github.com/DominikSerafin/vuebar directive in my project. Now depending on some var i want to use it in html or not.
Like this
<div v-bar>
//this div contains huge html like 1200 lines of code and doing
// v-if is not option since i will have to duplicate all of its content
</div>
So to sumarize:
<div v-bar v-if="somevar"></div> // is not and option bceuse that div contains 1200 of code
Is there any way that i can say something like:
<div some_var ? v-bar:''></div>
Or to make my directive that sort of inherits that v-bar and renders?
Actually you can do one thing. Use Directive Hook Arguments.
You can put your condition based on the hook arguments inside the directive's code. And you can make sure the those hook arguments are reactive so that it could change when you want it to.
Write you logic whether to do something or not for directive inside the directive's code depending upon the binding values.
Read this, please comment if you are not clear.
No, there is no way to apply directive with some condition.
But you can try to create and destroy custom scroll bar programatically, from docs:
Public methods.
You can access them from your component context: this.$vuebar.
Alternatively you can access them from your main Vue instance:
Vue.vuebar. Every method needs to have passed Vuebar scroll container
element as the first argument. You can do that easily using $refs.
initScrollbar(DOM Element, options)
getState(DOM Element)
refreshScrollbar(DOM Element, options)
destroyScrollbar(DOM Element)
Here is an example:
<input name="TESTE" id="TESTE" placeholder="TESTE">
is there a way to do that?
<div name="TESTE">
<input :name="parent.name" :id="parent.name" :placeholder="parent.name">
</div>
I dont want to do that using vue data or components. Can i do that using only pure html like example above?
Thanks!!!
Unfortunately that's not possible. You'll need to use some sort of data field for this to work. Vue renders HTML according to the data you provide it and is otherwise unaware of the properties of surrounding elements. Your best bet is to either hard-code these values or add the appropriate data fields to reference.
It's generally better practice to use the data, anyway, as it will cut down maintenance time and mitigate issues with user error.
Is there an "easy" way to render a custom element in ag-grid header cell? The headercomponent interface seems like an overly cumbersome approach to a seemingly simple problem and I have not been successful with this approach. The closest I have come is to use something like:
header-cell-render.bind="myHeaderRenderer"
which is currently a function returning a string of HTML. While this "works" (though I understand it is deprecated), in the sense that the html is injected into the DOM, only primitive HTML renders. Meaning I can return something like:
<input type="checkbox" />
and it will render a checkbox, but I cannot return something like:
<my-custom-element></my-custom-element>
I can see that markup in the DOM, but the element doesn't "process", that is the Aurelia aspect of the control is not executed.
I am using the latest versions of ag-grid, ag-grid-aurelia.
Any help would be greatly appreciated.
This is currently not possible out of the box with ag-grid-aurelia.
This is because ag-grid-aurelia makes no special handling for this binding. The proper way to handle this is using replaceable parts which allows you to specify a template for Aurelia to inject and consume. ag-grid makes this a bit harder since it seems the only native tool for injecting content into the header is by passing an HTML string or an HTML element in the column configuration. This can likely be added to the ag-grid-aurelia library by using a combination of replaceable parts and the #children decorator to gain access to the aurelia-rendered header element and pass it to the column configuration.