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Filtering a stack trace array in vuejs

I am looking for some good ideas on how to filter an array that contains a stack trace. I have a database table that has four columns, one with the stack trace error messages, one that shows the priority of the error, one that shows the date the error was registered and finally a column that displays an custom made error message, which I have placed on multiple try-blocks around my system.
On the frontend I am fetching the data with axios and placing it inside an object called errors. Then in my computed properties I create an array of fields that contain the individual columns from the database and their data. I use the Bootstrap table to output it.
<template>
<b-container>
<b-card class="mt-4">
<h5>{{ $t('events') }}</h5>
<b-table
:items="errors"
:fields="fields"
:per-page="[5, 10]"
sort-desc
primary-key="id"
/>
</b-card>
</b-container>
</template>
<script>
import {errorService} from '#/services/error';
import moment from 'moment';
export default {
components: {
CommonTable,
flapper
},
data() {
return {
errors: null,
};
},
computed: {
fields() {
return [
{
key: 'priority',
label: this.$t('errorLogs.priority'),
sortable: true
},
{
key: 'creationDateTime',
label: this.$t('creationDateTime'),
formatter: date => moment(date).locale(this.$i18n.locale).format('L'),
sortable: true
},
{
key: 'stackTrace',
label: this.$t('errorLogs.stackTrace'),
sortable: true
},
{
key: 'errorMessage',
label: this.$t('message'),
sortable: true
},
]
},
},
methods: {
load(){
errorService.getErrorLogs().then(result => {
this.errors = result.data
})
}
},
created() {
this.load()
}
};
</script>
It works as it should, but the output for the stack trace takes up way too much space in the table column.
Ideally it should only show
org.springframework.web.method.annotation.MethodArgumentTypeMismatchException
and then if the user wants more detail they can click on the stack trace and get the full version in a pop up or something.
I am guessing the easiest solution would be to filter the stack trace, so that it does not show any text beyong the : sign.
But how would I implement this in the setup that I currently have?
I am guessing in computed properties I need add a method to the stackTrace field.
So:
{
key: 'stackTrace',
label: this.$t('errorLogs.stackTrace'),
sortable: true
function: this.filteredStackTrace()
},
And then create a new method.
filteredStackTrace(){
this.errors.stackTrace.filter(some filter...)
}

Maybe something like following snippet:
const app = Vue.createApp({
data() {
return {
st: `Exception in thread "main" java.lang.NullPointerException
at com.example.myproject.Book.getTitle(Book.java:16)
at com.example.myproject.Author.getBookTitles(Author.java:25)
at com.example.myproject.Bootstrap.main(Bootstrap.java:14)`,
expanded: false
};
},
computed: {
firstLine() {
return this.st.split('\n')[0]
},
allLines() {
return this.st.split('\n').filter((item, idx) => idx !== 0).toString()
}
},
})
app.mount('#demo')
<script src="https://unpkg.com/vue#3/dist/vue.global.prod.js"></script>
<div id="demo">
{{ firstLine }}
<button #click="expanded = !expanded">all</button>
<div v-if="expanded">{{ allLines }}</div>
</div>

Displaying random text in Vue.js template

I have a simple Loader component in my Vue.js app that just displays one of messages, randomly. I did it like that:
Vue.component('Loader', {
data() {
const textEntries = [
'Just a second',
'Please wait',
'Almost there',
'And there we go',
];
return {
text: textEntries[Math.trunc(Math.random() * textEntries.length)]
};
},
template: '<p class="loading">{{ text }}...</p>'
});
I'm not sure if keeping this in data like that is fine. Won't my text ever get re-rendered with another text? Also, having the array in the data() method seems awkward. Would it be more suitable to use lifecycle hooks for that instead? Or computed property?

You should use the lifecycle hooks which Vue provides. More precisely, I believe that for your example, you should use the created hook. So your code will be like this:
Vue.component('Loader', {
created: function () {
this.$options.textEntries = [
'Just a second',
'Please wait',
'Almost there',
'And there we go',
];
this.$options.randomIndex = Math.trunc(Math.random() * textEntries.length);
},
data() {
return {
text: this.$options.textEntries[this.$options.randomIndex]
};
},
template: '<p class="loading">{{ text }}...</p>'
});
If you leave textEntries within the data Vue property, then you will not have access to it as it will be erased from the memory as soon as the data function is processed.
WARNING: The $options, which I am using, cannot be changed since it is read-only. For more information, I would redirect you to this.

As I know data() will called only once, so the text will be one of the textEntries
I think it's better to extract textEntries out of the data method(since it will not be changed, so it should not be generated each data() call.

The right way would be to define the array in data and get the random text as computed:
new Vue({
el:"#app",
data() {
return{
textEntries: [
'Just a second',
'Please wait',
'Almost there',
'And there we go',
]
}
},
computed:{
text: function(){
return this.textEntries[Math.trunc(Math.random() * this.textEntries.length)]
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<p class="loading">{{ text }}...</p>
</div>
If you want the text to be re-rendered every period of time, you can use setTimeout and keep track of the random index:
new Vue({
el:"#app",
data() {
return{
textEntries: [
'Just a second',
'Please wait',
'Almost there',
'And there we go',
],
index: 0
}
},
mounted(){
setInterval(function(){
this.index = Math.trunc(Math.random() * this.textEntries.length)
}.bind(this), 3000);
},
computed:{
text: function(){
return this.textEntries[this.index];
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<p class="loading">{{ text }}...</p>
</div>

v-on click, add handler only if condition has been met

After some research the following suggestion by Mr. Evan You was found:
https://github.com/vuejs/vue/issues/7349#issuecomment-354937350
So without any hesitation I gave it a try:
Component template
<template>
<div v-on='{ click: dataType === `section` ? toggleSectionElements : null }'>
... magic
</div>
<template>
JS Logic
<script>
export default {
name: `product-section`,
props: [`section`, `sectionName`, `depth`],
methods: {
toggleSectionElements() {
... magic
}
},
computed: {
dataType() {
if (this.$props.section.sections || this.$props.depth === 0) {
return `section`
} else {
return `element`
}
}
}
}
</script>
But for described case it results in error during rendering:
[Vue warn]: Invalid handler for event "click": got null
Can someone please suggest what has been done wrong? :thinking:
Update
The way Data Model looks like:
DataModel: {
mainSectionA: {
sections: {
sectionA: {
sections: {
elementA: { values: { ... } },
elementB: { values: { ... } }
}
values: { ... }
}
sectionB: {
elementA: { values: { ... } },
elementB: { values: { ... } }
}
},
values: { ... }
},
mainSectionB: {
sections: {
elementA: { values: { ... } },
elementB: { values: { ... } },
elementC: { values: { ... } },
... elements
},
values: { ... }
}
}

Just change it to the below and it will work
v-on="condition ? { mouseover: handler } : {}"
or, if your handler is called mouseover
v-on="condition ? { mouseover } : {}"

Instead of polluting your template with ternary logic, you should actually perform the check inside the click handler instead. It not only makes your template more readable, but also makes maintaining the code easier since all logic has been abstracted and delegated to the event handler's callback instead.
Quick solution
Therefore the quick solution is to actually ensure that the toggleSectionElements() will only work when a correct dataType is present. This can be achieved by using a guard clause:
toggleSectionElements() {
// Guard clause to prevent further code execution
if (this.dataType() !== 'section')
return;
// Magic here
}
Even better, is that if separate handlers should be assigned to each dataType: you can then create a factory function for that purpose:
methods: {
// This is just a factory function
toggleElements() {
switch (this.dataType()) {
case 'section':
return this.toggleSectionElements;
case 'element':
// Something else...
}
},
toggleSectionElements() {
// Magic for section element
}
}
Suggestion: using atomic components
Since it might be costly to bind click event handlers to elements that end up doing nothing, you can also break down your component to be more atomic. The collection element will be responsible of receiving an array of "section" or "element", and each "section"/"element" will have its own component, something like this:
You have a collection component, say <my-collection>, that holds all "section" and "element" components
"section" component will use the <my-section> component
"element" component will use the <my-element> component
This is when VueJS becomes really powerful: you can use dynamic component inside <my-collection> to determine which component to use depending on the dataType encountered.
This is done by running a v-for through the collection, and then using v-bind:is="..." to determine whether a specific collection item should be using "section" or "element". I understand that this is probably going to go out of scope of your original question, but it's a worthwhile design to consider:
const collectionComponent = Vue.component('my-collection', {
template: '#my-collection-component',
data: function() {
return {
collection: [{
dataType: 'section',
description: 'Hello I am section 1'
}, {
dataType: 'element',
description: 'Hello I am element 1'
}, {
dataType: 'section',
description: 'Hello I am section 2'
}, {
dataType: 'element',
description: 'Hello I am element 2'
}]
}
},
methods: {
componentToUse(dataType) {
return 'my-' + dataType;
}
}
});
const sectionComponent = Vue.component('my-section', {
template: '#my-section-component',
props: ['itemData'],
methods: {
toggle() {
console.log('Doing some magic.');
}
}
});
const elementComponent = Vue.component('my-element', {
template: '#my-element-component',
props: ['itemData']
});
new Vue({
el: '#app'
});
.box {
border: 1px solid #999;
cursor: pointer;
margin: 10px;
padding: 10px;
}
.box:hover {
background-color: #eee;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.17/vue.js"></script>
<div id="app">
<my-collection />
</div>
<script type="text/x-template" id="my-collection-component">
<div>
<component
v-for="(item, i) in collection"
v-bind:key="i"
v-bind:is="componentToUse(item.dataType)"
v-bind:itemData="item" />
</div>
</script>
<script type="text/x-template" id="my-section-component">
<div #click="toggle" class="box">
<h1>{{ itemData.dataType }}</h1>
<p>{{ itemData.description }}</p>
<p>Clicking on me will invoke a section-specific logic</p>
</div>
</script>
<script type="text/x-template" id="my-element-component">
<div class="box">
<h1>{{ itemData.dataType }}</h1>
<p>{{ itemData.description }}</p>
<p>Clicking on me will do nothing</p>
</div>
</script>

here:
click: dataType === `section` ? toggleSectionElements : null
in the not-equal case you pass null, but the value on click expects a function. you can try an emptry function:
click: dataType === `section` ? toggleSectionElements : ()=>{}

In Vue 3 you can pass null to the listener. Combining it with optional chaining you can do this:
#click="handler?.() || null"
Same for old browsers:
#click="handler ? handler() : null"

How to pass VueJS data to another script?

I'm converting an established site over to VueJS but hit a stumbling block on the best way to achieve this.
It's using D3-Funnel (https://github.com/jakezatecky/d3-funnel) to draw a funnel chart but how do I pass VueJS data variables to the charts constructor?
<script>
const data = [
{ label: 'Step 1', value: this.step1 },
{ label: 'Step 2', value: this.step2 },
.......
];
const options = {
block: {
dynamicHeight: true,
minHeight: 15,
},
};
const chart = new D3Funnel('#funnel');
chart.draw(data, options);
</script>
So I need to pass vue data variables into the values. My first thought is to move this into it's own function in the VueJS methods object and use the variables there using this.
Is there a better way of achieving this?
---------- Edit -------------
As per comments people wanted to see how I achieved this currently in vue. As already mentioned above I just created a function in the vue methods object and then call it.
methods : {
drawChart(){
const data = [
{ label: 'Step 1', value: 99999 },
{ label: 'Step 2', value: 9999 },
.......
];
const options = {
block: {
dynamicHeight: true,
minHeight: 15,
},
};
const chart = new D3Funnel('#funnel');
chart.draw(data, options);
}
},
mounted(){
this.drawChart();
}
Data is coming from an API and put into the vue data object.
data:{
step1: 0,
step2: 0,
....
},
methods:{
getData(){
axois.post......
response{
this.step1 = response.data.step1
this.step2 = response.data.step2
....
}
}
}

As I understand it you are trying to pass information down to a component and use it. If you are using single file components and webpack you can do something like this which is put together with examples listed on the vue website.
You can also take a look at this guys approach
App.vue
...
<my-d3-component :d3data="d3Data"></my-d3-component>
...
<script>
import d3Component from 'path/to/component'
var app = new Vue({
el: '#app',
data: {
d3Data: {}
},
components: {
'my-d3-component': d3Component
}
})
</script>
d3Component.vue
<template>
d3 html stuff goes here
</template>
<script>
export default {
props: ['d3Data'],
data() {
return {}
},
mounted: {
const options = {
block: {
dynamicHeight: true,
minHeight: 15,
},
};
const chart = new D3Funnel('#funnel');
chart.draw(this.d3Data, options);
}
}
</script>

Is there any way to have multiple Vues have a computed listener working on the same value?

Setup:
I have multiple Vue components, and each component has multiple instances in different dialogs in my web app.
For each type of component I have a global state (handrailOptions in the example below) so that each type of component stays in sync across the dialogs.
I'd like for it so that when a component proceeds beyond step 1, I hide the other components in that dialog.
I have achieved this nicely using the computed / watch combo.
However, my problem is that it seems if I try to listen in with computed through more than 1 Vue instance, it hijacks the other listeners.
Problem
Below is a simplified version of what I'm working with, when the app starts up, the console logs 'computed 1' & 'computed 2'. But then when I change handrailOptions.step, only the second fires. ('computed 2' & 'watched 2')
Is there any way to have multiple Vues have a computed listener working on the same value?
handrailOptions = {
step: 1
};
Vue.component( 'handrail-options', {
template: '#module-handrail-options',
data: function() {
return handrailOptions;
},
});
var checkoutDialog = new Vue({
el: '#dialog-checkout',
computed: {
newHandrailStep() {
console.log('computed 1');
return handrailOptions.step;
}
},
watch: {
newHandrailStep( test ) {
console.log('watched 1');
}
}
});
new Vue({
el: '#dialog-estimate-questions',
computed: {
newHandrailStep() {
console.log('computed 2');
return handrailOptions.step;
}
},
watch: {
newHandrailStep( test ) {
console.log('watched 2');
}
}
});

This works as expected. I made handrailOptions responsive by making the data object of a new Vue. Making it the data object of a component, as you did, could also work, but the component would have to be instantiated at least once. It makes more sense to have a single object for your global, anyway.
handrailOptions = {
step: 1
};
// Make it responsive
new Vue({data: handrailOptions});
var checkoutDialog = new Vue({
el: '#dialog-checkout',
computed: {
newHandrailStep() {
console.log('computed 1', handrailOptions.step);
return handrailOptions.step;
}
},
watch: {
newHandrailStep(test) {
console.log('watched 1');
}
}
});
new Vue({
el: '#dialog-estimate-questions',
computed: {
newHandrailStep() {
console.log('computed 2', handrailOptions.step);
return handrailOptions.step;
}
},
watch: {
newHandrailStep(test) {
console.log('watched 2');
}
}
});
setInterval(() => ++handrailOptions.step, 1500);
<script src="//cdnjs.cloudflare.com/ajax/libs/vue/2.3.4/vue.min.js"></script>
<div id="dialog-estimate-questions">
Main step {{newHandrailStep}}
</div>
<div id="dialog-checkout">
CD step {{newHandrailStep}}
</div>