Conflict on template of Tornado and Vue - vuejs2

I'm a newbie to both these frameworks and the first thing I found is a conflict. So because the double curly brackets are reserved by Tornado, I changed the Vue's default ones to single ones:
new Vue({
el: '#app',
delimiters: ['${', '}'],
data: {
message: 'Hello Vue.js!'
}
Template:
<td>${ message }</td>
But now it's just not rendered, what I see in a browser is:
${ message }
How to solve this conflict? Am I doing something wrong?
Thanks!
UPD I figured it out. I did several things wrong:
1) I put the script at the "head" section instead of the very end.
2) I didn't add id="app" attribute to some parent element to specify the app object.
After I changed the code everything started working.

Another way to combine Tornado with another template system that uses double-braces is to escape the ones that are to be handled by javascript with {{!:
<h1>This variable comes from Tornado: {{ x }}</h1>
<p>This one comes from Vue: {{! y }}</p>
Tornado's rendering will remove the exclamation point and leave the double braces for Vue to use.

I encountered that as well. This is what worked for me.
Put this in your main.js. N.B you can specify the delimiters to suit your needs
Vue.mixin({ delimiters: ['[[',']]'] })
The in your html you can use it as it is. e.g
<td>[[ message ]]</td>

Related

Vue Template - Making any URLs found in returned text string to a link

I am working on a project that is Vue modular based (code used is: https://github.com/mishushakov/dialogflow-web-v2/blob/bc3ce7d7cf8e09a34b5fda431590bd48cc31f66b/src/App.vue)
Linking to the file I think need to make the change to, have been trying but I don't really know Vue at all and had not luck.
The returned message is plain text for example: this is a test message, please visit https://wwww.google.com
What I am trying to do, is from that text string, if a URL found is to create a link from that found URL
<RichComponent><RichBubble v-if="message.queryResult.fulfillmentText" :text="message.queryResult.fulfillmentText" /></RichComponent>
Is what the current code is that returns the data.
Is there a best way to achieve this? Is there a core function maybe?
I have tried to npm install linkify but cannot seem to get it working so maybe a direct approach would be better?
You can use linkifyjs to convert links in a string into anchor tags. The linkifyjs/lib/linkify-string.js file augments the String prototype with a linkify() method.
<template>
<p v-html="msg.linkify()"></p>
</template>
<script>
import 'linkifyjs/lib/linkify-string' // side effect: creates String.prototype.linkify
export default {
props: ['msg'],
}
</script>
It also exports that method if you prefer an explicit call:
<template>
<p v-html="linkify(msg)"></p>
</template>
<script>
import linkify from 'linkifyjs/lib/linkify-string'
export default {
props: ['msg'],
methods: {
linkify,
}
}
</script>

Vuetify TreeView displayed incorrectly

I'm a beginner in Vue, so please bear with my question.
I try to create a simple selectable tree, but for some reason it is displayed incorrectly. Instead of buttons, words remain.
I can't think of anything else I could have forgotten to do.
I tried adding a link to the vuetify CSS file (import 'verify/disk/verify.min. css';), but after that the image becomes even less readable. The link to material design icons is in the file index.html
How can I fix this, please?
Without CSS:
With CSS:
You are using Vuetify 2.x and it (contrary to 1.x) requires that in your Vue constructor
new Vue({
el: "#app",
components: { App },
template: "<App/>",
vuetify: new Vuetify() // <--- the important thing !!!
});
Also - you should wrap your content (in App.vue) inside <v-app> - otherwise the arrow icons on tree nodes will not switch between expanded/collapsed.

Using vue.js without NPM or CLI

I'd like to use Vue.js within one page of a large legacy application. The idea is to replace the old JS+jQuery hodge-podge within a single page -- but leave the rest of the app (many other pages) untouched. So, not interested in using NPM, Node, Vue CLI, Webpack, Babel, etc., just yet.
This is a proof-of-concept before we invest in refactoring the entire frontend of the application.
The approach we followed was to include vue.js via as explained here: https://v2.vuejs.org/v2/guide/installation.html#Direct-lt-script-gt-Include in that one page, and the use Vue only within that one page. This is the general page layout:
<html>
<head>
...
<script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
...
</head>
<body>
<div id="el">
... vue template ...
</div>
<script>
...
var vm = new Vue({
el : '#el',
data : {
config : <% config.json %> // this is server-rendered, using server templating
...
},
...
});
...
</script>
</body>
</html>
The page does work. However, I get the following error/warning within the Vue console:
Templates should only be responsible for mapping the state to the UI. Avoid placing tags with side-effects in your templates, such as <script>, as they will not be parsed.
Although I'd rather not, I can certainly move the page-specific JS to its own separate file (and that does eliminate the warning/error). However, I wouldn't be able to set vm.config with server-provided data along with the loaded page by using server-side template, e.g. config : <% config.json %>. I know I could GET it using JS separately, after pageload, via an AJAX call directly from the server, but for practical reasons I'd like to avoid doing that here.
I'd greatly appreciate any suggestions on how to get this to work nicely. I'm also open to other suggestions with regard to this general pattern, that don't involve retooling the front-end just yet.
And perhaps the answer is to ignore the warning, or somehow disable it, given the page does work as intended...
Thank you!
One simple solution here is to write it to the global window object. IIRC SSR frameworks like Angular universal/Nuxt/Next/... all use this approach.
window.__STATE__ = <% config.json %>
In your JS file you can then refer to the window.__STATE__ object.
var vm = new Vue({
el: '#el',
data: {
config: window.__STATE__
}
})
Ofcourse the order is important here:
<body>
<script>
window.__STATE__ = <% config.json %>
</script>
<script src="app.js"></script>
</body>
Grrr, after several days after enduring this error, I discovered this:
<fieldset id="el">
...
<div id="el">
...
</div>
...
</fieldset>
So the issue was repeating #el within same page.
My mistake.
Just wish the error message emitted by Vue had been a bit more useful!
Bottom line: The pattern described in the origional question works just fine without NPM/CLI.

VueJS in Blade Template without Build Step

I'm trying to implement VueJS in one of my pages blade template. I just want to use Vue in that single template.
I tried the following:
default.blade.php
//...
#yield('js-for-layout-before')
<script src="{{ asset('js/vue.min.js') }}"></script>
// ...
view.blade.php
#extends('layouts.default')
//...
#section('content')
<div id="app">
<ol>
<todo-item></todo-item>
</ol>
<p>#{{ message }}</p>
</div>
<script type="module" src="{{ asset('js/pages/vue_component.js') }}"></script>
#stop
vue_component.js
Vue.component('todo-item', {
template: '<li>This is a list item</li>'
})
new Vue({
el: '#app',
data: {
message: 'Hello Vue.js!'
}
})
With this, I am only getting a blank page. There are no errors in the console, all files are loaded.
The inspector shows what I mean:
I do not want to implement a build step or anything, just a minimum setup with vue. Any ideas what I am missing here?
--UPDATE:
I replaced vue.min.js with the development version and finally got a clue:
vue.js:633 [Vue warn]: It seems you are using the standalone build of
Vue.js in an environment with Content Security Policy that prohibits
unsafe-eval. The template compiler cannot work in this environment.
Consider relaxing the policy to allow unsafe-eval or pre-compiling
your templates into render functions.
For reference, the issue was that my CSP didn't allow for unsafe-eval, which is required in this scenario without a build step. I didn't notice this until I included vue.js instead of the minified vue.min.js, which doesn't show errors.
To fix this for now, I did the following, though you should probably not do this in production: Check where your CSP is defined and add 'unsafe-eval' to "script-src".
In production, you probably want to use nonce on the script instead of unsafe-eval and something like https://github.com/spatie/laravel-csp to generate the nonce.

vue: Uncaught TypeError: Cannot read property ... of undefined

I'm using vue#2.1.3 and the vue official webpack template to build an app.
When developing locally, I often see the warning Uncaught TypeError: Cannot read property ... of undefined, but the HTML can be rendered successfully. However, the HTML can't be rendered when it's deployed to Netlify with npm run build command. So I have to treat this warning seriously.
I learned from here that it's because "the data is not complete when the component is rendered, but e.g. loaded from an API." and the solution is to "use v-if to render that part of the template only once the data has been loaded."
There are two questions:
I tried wrap v-if around multiple statements that's generating the warning but personal I think this solution is verbose. Is there a neat approach?
"warnings" in local development turn into "fatal errors"(HTML can't be rendered) in production. How to make them the same? e.g. both of them issue warnings or errors?
Just use v-if on a common parent to all the elements in your template relying on that AJAX call, not around each one.
So instead of something like:
<div>
<h1 v-if="foo.title">{{ foo.title }}</h1>
<p v-if="foo.description">{{ foo.description }}</p>
</div>
Do
<div>
<template v-if="foo">
<h1>{{ foo.title }}</h1>
<p>{{ foo.description }}</p>
</template>
</div>
have you tried to initialize all the data you need? e.g. if you need a b c, you can do:
new Vue({
data: {
a: 1,
b: '',
c: {}
},
created(){
// send a request to get result, and assign the value to a, b, c here
}
})
In this way you wont get any xx is undefined error
Guys are right but I can add something.
If there is possibility that your root element in the condition can be undefined for some reason, it is good practice to use something like that: v-if='rootElement && rootElement.prop'. It will secure you from getting cannot get property prop of undefined as when rootelement is undefined, it will not go further in checking.
2021 vue3
we can use like this
props: {
form: {
type: String,
required: true,
},
setup(props, context) {
console.log(props.form)