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Vue returning data objects from axios call to controller

I'm using vue in laravel and trying to get a controller function that I'm hitting to return the data so that I can use it in the data() section of my vue template.
I know the controller function returns what I need, but I'm not so sure how I need to handle the return/response in the axios call in order to start placing the data into the data() function in vue
Blade/Vue template
import moment from 'moment'
export default {
name: 'calendar',
data () {
return {
events: [
{
title: 'test',
allDay: true,
start: '2019-08-17',
},
],
config: {
defaultView: 'month',
eventRender: function(event, element) {
console.log(event)
}
},
}
},
created() {
this.fetchTasks();
},
methods: {
fetchTasks() {
axios.get('/landing/tasks' )
.then((response) => {
// handle success
this.assetOptions = response.data;
})
.catch(function (error) {
// handle error
console.log(error);
})
.finally(function () {
});
}
}
}
Route
Route::get('/landing/tasks', 'landingController#getTasks')
->name('landing/tasks');
Controller
public function getTasks()
{
$getTask = Task::getTaskForLanding();
$result = array();
foreach($getTask as $id => $task){
$result[$task->taskt_id][] = $task;
}
}

If you are certain that the Controller returns what you need, the only thing you are missing is declaration of assetOptions. To be able to assign response.data to assetOptions later on, you have to declare it in the data function first.
data() {
return {
...
assetOptions = []; // assuming you are expecting an array
...
};
}
Once that is done, you are all set.

Global loaded data in VueJs is occasionally null

I'm new to VueJs and currently trying to load some data only once and make it globally available to all vue components. What would be the best way to achieve this?
I'm a little bit stuck because the global variables occasionally seem to become null and I can't figure out why.
In my main.js I make three global Vue instance variables:
let globalData = new Vue({
data: {
$serviceDiscoveryUrl: 'http://localhost:40000/api/v1',
$serviceCollection: null,
$clientConfiguration: null
}
});
Vue.mixin({
computed: {
$serviceDiscoveryUrl: {
get: function () { return globalData.$data.$serviceDiscoveryUrl },
set: function (newUrl) { globalData.$data.$serviceDiscoveryUrl = newUrl; }
},
$serviceCollection: {
get: function () { return globalData.$data.$serviceCollection },
set: function (newCollection) { globalData.$data.$serviceCollection = newCollection; }
},
$clientConfiguration: {
get: function () { return globalData.$data.$clientConfiguration },
set: function (newConfiguration) { globalData.$data.$clientConfiguration = newConfiguration; }
}
}
})
and in my App.vue component I load all the data:
<script>
export default {
name: 'app',
data: function () {
return {
isLoading: true,
isError: false
};
},
methods: {
loadAllData: function () {
this.$axios.get(this.$serviceDiscoveryUrl)
.then(
response => {
this.$serviceCollection = response.data;
let configurationService = this.$serviceCollection.services.find(obj => obj.key == "ProcessConfigurationService");
this.$axios.get(configurationService.address + "/api/v1/clientConfiguration").then(
response2 => {
this.$clientConfiguration = response2.data;
}
);
this.isLoading = false;
})
}
},
created: function m() {
this.loadAllData();
}
}
</script>
But when I try to access the $clientConfiguration it seems to be null from time to time and I can't figure out why. For example when I try to build the navigation sidebar:
beforeMount: function () {
let $ = JQuery;
let clients = [];
if (this.$clientConfiguration === null)
console.error("client config is <null>");
$.each(this.$clientConfiguration, function (key, clientValue) {
let processes = [];
$.each(clientValue.processConfigurations, function (k, processValue) {
processes.push(
{
name: processValue.name,
url: '/process/' + processValue.id,
icon: 'fal fa-project-diagram'
});
});
clients.push(
{
name: clientValue.name,
url: '/client/' + clientValue.id,
icon: 'fal fa-building',
children: processes
});
});
this.nav.find(obj => obj.name == 'Processes').children = clients;

The most likely cause is that the null is just the initial value. Loading the data is asynchronous so you'll need to wait for loading to finish before trying to create any components that rely on that data.
You have an isLoading flag, which I would guess is your attempt to wait for loading to complete before showing any components (maybe via a suitable v-if). However, it currently only waits for the first request and not the second. So this:
this.$axios.get(configurationService.address + "/api/v1/clientConfiguration").then(
response2 => {
this.$clientConfiguration = response2.data;
}
);
this.isLoading = false;
would need to be:
this.$axios.get(configurationService.address + "/api/v1/clientConfiguration").then(
response2 => {
this.$clientConfiguration = response2.data;
this.isLoading = false;
}
);
If it isn't that initial value that's the problem then you need to figure out what is setting it to null. That should be prety easy, just put a debugger statement in your setter:
$clientConfiguration: {
get: function () { return globalData.$data.$clientConfiguration },
set: function (newConfiguration) {
if (!newConfiguration) {
debugger;
}
globalData.$data.$clientConfiguration = newConfiguration;
}
}
Beyond the problem with the null, if you're using Vue 2.6+ I would suggest taking a look at Vue.observable, which is a simpler way of creating a reactive object than creating a new Vue instance.
Personally I would probably implement all of this by putting a reactive object on Vue.prototype rather than using a global mixin. That assumes that you even need the object to be reactive, if you don't then this is all somewhat more complicated than it needs to be.

How to pass data from one function to another function that is an argument of the first function

In the below example, when using getData();, is it possible to access the data contained in its object map within a new function – ie. useData(); – that is an argument of getData();?
const getData = (useData) => {
const myData = {
0: { title: 'Hello' },
1: { title: 'World!' }
};
Object.keys(myData).map((item) => {
useData();
});
}
getData(console.log(
/**
* Somehow access data represented by `myData` and `item`
* in above object map along the lines of `myData[item].title`
*/
));

Do you want to achieve something like that?
You can call useData with some arguments inside map function. You can't call some function like console.log as argument to getData function in this case.
const getData = useData => {
const myData = {
0: { title: "Hello" },
1: { title: "World!" },
};
Object.keys(myData).map(item => {
useData(myData[item]);
});
};
getData(console.log);

Yes, that is the default behaviour. But you need to pass a function(console.log) instead of a function invocation(console.log()) and invoke it only later.
const getData = (useData) => {
const myData = {
0: { title: 'Hello' },
1: { title: 'World!' }
};
Object.keys(myData).map((item) => {
useData.apply(console, [item]);
useData.apply(console, [ myData[item].title ]);
//or useData(myData[item].title)
});
}
getData(console.log);
getData(console.log('something'));
is same as:
let x = console.log('something');
getData(x);

How to add a function to Object's named property with correct context in javascript

I have a working piece of code as below:
let pageParams = {
data: { todos: [], desc: '' }
}
pageParams.onLoad = function () {
//I am trying to encapsulate this to a standalone function and
// make it generic, instead of hard coding the 'this.addTodo=XXX'
const evProducer = {
start: listener => {
//Here, I am adding a named property function
this.addTodo = ev => {
listener.next(ev.detail.value)
}
},
stop: ()=>{}
}
const input$ = xs.create(evProducer)
input$.compose(debounce(400)).subscribe({
next: val => console.log(val)
})
}
The code works and now I am going to do some refactor work, i.e. move the logic out of this onLoad function. So I move the logic to another module
let xsCreator = {}
xsCreator.fromEvent = function(handler){
const evProducer = {
start: listener => {
handler = ev => listener.next(ev.detail.value)
},
stop: () => {}
}
return xs.create(evProducer)
}
And in the previous onLoad function becomes the following:
pageParams.onLoad = function () {
xs.fromEvent(this.addTodo).subscribe(blablabla)
}
but it does not work. I guess I might use apply/call/bind to make this work, but don't know how to. Anyone can help? Thanks in advance

I've found the solution, I should use Object.defineProperty to add a named property for object.
xsCreator.fromInputEvent = (srcObj, propertyName) => {
const evProducer = {
start: (listener) => {
Object.defineProperty(
srcObj,
propertyName,
{value: ev => listener.next(ev.detail.value)})
},
stop: () => {}
}
return xs.create(evProducer)
}

Unsubscribe from Redux store when condition is true?

I'm employing the suggestion from #gaearon to setup a listener on my redux store. I'm using this format:
function observeStore(store, select, onChange) {
let currentState;
if (!Function.prototype.isPrototypeOf(select)) {
select = (state) => state;
}
function handleChange() {
let nextState = select(store.getState());
if (nextState !== currentState) {
currentState = nextState;
onChange(currentState);
}
}
let unsubscribe = store.subscribe(handleChange);
handleChange();
return unsubscribe;
}
I'm using this in an onEnter handler for a react-router route:
Entity.onEnter = function makeFetchEntity(store) {
return function fetchEntity(nextState, replace, callback) {
const disposeRouteHandler = observeStore(store, null, (state) => {
const conditions = [
isLoaded(state.thing1),
isLoaded(state.thing2),
isLoaded(state.thing3),
];
if (conditions.every((test) => !!test) {
callback(); // allow react-router to complete routing
// I'm done: how do I dispose the store subscription???
}
});
store.dispatch(
entities.getOrCreate({
entitiesState: store.getState().entities,
nextState,
})
);
};
};
Basically this helps gate the progression of the router while actions are finishing dispatching (async).
My problem is that I can't figure out where to call disposeRouteHandler(). If I call it right after the definition, my onChange function never gets a chance to do it's thing, and I can't put it inside the onChange function because it's not defined yet.
Appears to me to be a chicken-egg problem. Would really appreciate any help/guidance/insight.

How about:
Entity.onEnter = function makeFetchEntity(store) {
return function fetchEntity(nextState, replace, callback) {
let shouldDispose = false;
const disposeRouteHandler = observeStore(store, null, (state) => {
const conditions = [
isLoaded(state.thing1),
isLoaded(state.thing2),
isLoaded(state.thing3),
];
if (conditions.every((test) => !!test) {
callback(); // allow react-router to complete routing
if (disposeRouteHandler) {
disposeRouteHandler();
} else {
shouldDispose = true;
}
}
});
if (shouldDispose) {
disposeRouteHandler();
}
store.dispatch(
entities.getOrCreate({
entitiesState: store.getState().entities,
nextState,
})
);
};
};
Even though using the observable pattern leads to some buy-in, you can work around any difficulties with normal js code. Alternatively you can modify your observable to suit your needs better.
For instance:
function observeStore(store, select, onChange) {
let currentState, unsubscribe;
if (!Function.prototype.isPrototypeOf(select)) {
select = (state) => state;
}
function handleChange() {
let nextState = select(store.getState());
if (nextState !== currentState) {
currentState = nextState;
onChange(currentState, unsubscribe);
}
}
unsubscribe = store.subscribe(handleChange);
handleChange();
return unsubscribe;
}
and
Entity.onEnter = function makeFetchEntity(store) {
return function fetchEntity(nextState, replace, callback) {
const disposeRouteHandler = observeStore(store, null, (state, disposeRouteHandler) => {
const conditions = [
isLoaded(state.thing1),
isLoaded(state.thing2),
isLoaded(state.thing3),
];
if (conditions.every((test) => !!test) {
callback(); // allow react-router to complete routing
disposeRouteHandler();
}
}
store.dispatch(
entities.getOrCreate({
entitiesState: store.getState().entities,
nextState,
})
);
};
};
It does add a strange argument to onChange but it's just one of many ways to do it.
The core problem is that handleChange gets called synchronously immediately when nothing has changed yet and asynchronously later. It's known as Zalgo.

Inspired by the suggestion from #DDS, I came up with the following alteration to the other pattern mentioned in #gaearon's comment:
export function toObservable(store) {
return {
subscribe({ onNext }) {
let dispose = this.dispose = store.subscribe(() => {
onNext.bind(this)(store.getState())
});
onNext.bind(this)(store.getState());
return { dispose };
},
dispose: function() {},
}
}
This allows me to invoke like:
Entity.onEnter = function makeFetchEntity(store) {
return function fetchEntity(nextState, replace, callback) {
toObservable(store).subscribe({
onNext: function onNext(state) {
const conditions = [/* many conditions */];
if (conditions.every((test) => !!test) {
callback(); // allow react-router to complete routing
this.dispose(); // remove the store subscription
}
},
});
store.dispatch(/* action */);
};
};
The key difference is that I'm passing a regular function in for onNext so as not to interfere with my bind(this) in toObservable; I couldn't figure out how to force the binding to use the context I wanted.
This solution avoids
add[ing] a strange argument to onChange
... and in my opinion also conveys a bit more intent: this.dispose() is called from within onNext, so it kinda reads like onNext.dispose(), which is exactly what I want to do.