Dynamically invoking module.config() is blocked - angularjs

Rather than running config at the initial stage, I would like to config something at a later stage based on some information fetched from server like this:
$http.get(url)
.success( function(response){
angular.module('MyApp').config(['$myServiceProvider', function( $myServiceProvider){
$myServiceProvider.enableSomething(true); // delayed !!!
}]);
});
However the running of the body of config() function is blocked until I loaded some lazy-loaded partial. Maybe a $compile() will trigger it.
I do not understand why it is like this and how to make the config() body invoked immediately.
Thanks.

The angular-deferred-bootstrap module does that exactly : https://github.com/philippd/angular-deferred-bootstrap
See : https://github.com/philippd/angular-deferred-bootstrap#attach-constants-to-specific-modules
Also, this question offers other options : AngularJS : Initialize service with asynchronous data

Would it be possible in your scenario to use $http in a module.run call and configure your service in the $http's success handler?
If it absolutely needs to happen before the module.configcall, remove ng-app from your HTML and do the bootstrapping yourself by calling angular.bootstrap as outlined in the documentation after you have fetched the file.
As far as I'm aware, there's no way of blocking the configuration phase.

Related

Set app.config within a controller

So, I have my app.controller and inside of it I have a request. When request is successful, I want to set retrieved data to some $provider property, i.e.
app.controller('someCtrl', function(){
app.config(function($someProvider){
$someProvider.property = response.data;
$someProvider.function(response.data.status);
})
})
I'm trying to set this within controller, but it does nothing. Any tips, guys? :)
if default injecting doesn't do the job
maybe store your provider at config time to some other variable and use this var in controller later
but angular says:
During application bootstrap, before Angular goes off creating all services, it configures and instantiates all providers. We call this
the configuration phase of the application life-cycle. During this
phase, services aren't accessible because they haven't been created
yet.
Once the configuration phase is over, interaction with providers is
disallowed and the process of creating services starts. We call this
part of the application life-cycle the run phase.
so i don't know if this will work
Newly added config blocks aren't executed after the ending of config phase, the same applies to other app methods because they result in additional config blocks internally.
It is possible with:
app.config(($provide, $someProvider) => {
$provide.value('$someProvider', $someProvider);
});
app.controller('someCtrl', ($someProvider) => {
$someProvider...
});
This voids the warranty and may indicate XY problem that should be solved the other way, depending on what $someProvider is and how it functions.
If $some is injected and used before setting $someProvider, this will result in race condition. If $some was changed at some point to not watch for $someProvider properties after instantiation, this will result in breaking changes without notice that will make the tests fail.
It is acceptable for badly designed third-party services that don't cause ill effects when being treated like that. And as any other hack, it should be thoroughly covered with tests.
Your question comes down to how can I postpone angular's bootstrap process until I have some async data.
For the async part, you can use (or do) whatever you want, it doesn't really matter. Fun fact: You can even use $http before bootstrapping angular just by getting it via angular.injector(["ng"]).get("$http");.
This being said, when you have all your async data, all that's left to do is to bootstrap angular. This can be achieved via angular.bootstrap - source.
Here's a working example in which I asynchronously attach a controller (remember, you can do whatever you want: attach various constants, config blocks, etc). I've used setTimeout for simplicity's sake.
// Initial Angular Code
angular.module('myApp', []);
// Async function. I've used setTimeout for simplicity's sake
setTimeout(function() {
angular
.module('myApp')
.controller('MyCtrl', ['$scope',
function($scope) {
$scope.value = 'Angular has started!';
}
]);
// Boostrap AngularJS
angular.bootstrap(document.getElementById('boostrap-me'), ['myApp']);
}, 1000);
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.5.7/angular.min.js"></script>
<div id="boostrap-me" ng-controller="MyCtrl">
<div ng-bind="value">Angular hasn't yet bootstrapped as we're waiting for some async data!</div>
</div>

$viewContentLoaded is executed before initializing root scope

Method on $viewcontentloaded is firing asynchronously. To detail my problem, I have a variable in root scope i.e. my Main controller, which need to be initialized before my view controller loads. In module.run I am calling a sync function to initialize $rootScope.session. And In my view controller of a route, I am checking the status of session in afunction that is called like
$scope.$on('$viewContentLoaded', function() {
$scope.initialize();
});
But some times on page refreash, I am getting an undefined value for $rootScope.session, as It may have initialized later. So, Is there any way to make this synchronous like rootscope will be initialized before view loads. And for curiosity, how it will affect, if I call the $scope.initialize(); normally in my controller, in $viewContentLoaded or in $routeChangeSuccess.
Thanks in advance.
So, Is there any way to make this synchronous like rootscope will be initialized before view loads.
Use the $controller service to manually create the controller, as in a unit test.
$controllerProvider.register('FooCtrl', FooCtrl);
ctrl = $controller('FooCtrl', {$scope: scope});
Or $broadcast a custom event from the main controller down to the child:
function mainCtrl($rootScope)
{
$rootScope.$broadcast('abc');
}
function secondCtrl($scope)
{
$scope.$on('abc', function(event) { $scope.initialize(); });
}
Or use a try/catch block and a recursive call with a timer.
These are more or less the steps that you would take to implement lazy loading in AngularJS. In summary, you would first define your app module to keep instances of the relevant providers. Then you would define your lazy artifacts to register themselves using the providers rather than the module API. Then using a ‘resolve’ function that returns a promise in your route definition, you would load all lazy artifacts and resolve the promise once they have been loaded. This ensures that all lazy artifacts will be available before the relevant route is rendered. Also, don’t forget to resolve the promise inside $rootScope.$apply, if the resolution will be happening outside of AngularJS. Then you would create a ‘bootstrap’ script that first loads the app module before bootstrapping the app. Finally, you would link to the bootstrap script from your ‘index.html’ file.
References
AngularJS source: controllerSpec.js
Ifeanyi Isitor: Lazy Loading In AngularJS
AngularJS Lazy Loading with Require.js
Split Large AngularJS Controllers using the Mixin Pattern

Right way to tell all directives that data has already loaded

I have SPA and on the first page I load a big data object from the REST service.
The first page consists of the main part which resolved by controller, set of directives in the current scope which render some parts of received object and a header directive in the $rootscope which also render some part of received data.
I call API in the controller and when all data will be loaded I should notify about it all related directives for rendering loaded data.
Now I use $watch() and $watchGroup() for the same scope directives and $rootScope.$broadcast() for the header from the $rootscope.
Is there any more gracefully solution for it?
What is the best way to do this?
This sounds like a good use case for ngResource, which is an official Angular module for REST resources. I'd recommend you create a service for your resource like:
app.factory('Widget', function ($resource) {
return $resource('/api/v1/widgets/:id');
});
Then you can use it in your controller to handle the loading of your data.
app.controller('WidgetController', function ($scope, Widget) {
$scope.widgets = Widget.query({active: true});
});
In your views/templates/whatever, can bind right to widgets, which will be an array of widgets that match the query. The array will be empty while the widgets load, then it will be populated with the results -- and the binding will automatically update.
You can also bind to widgets.$resolved which (essentially) indicates whether the resource has finished loading or not.
Check out more about ngResource here.

AngularJS: reload template after api returned data

As my app initializes, the call to the api happens:
.run(function($ionicPlatform, $http, $localstorage, $model) {
$http.get($model.apiurl).success(function(data) {
$localstorage.setObject('data', data);
// reload template here!
});
})
When the api call has succeeded and the localstorage object is set, I want to reload my template (tab-categories.html) so the data can be displayed. How do I do this, ngRoute, stateProvider, ... ?
You might be missing the point of angular if you ask this question. If your template has values which are bound to a model, then changing those values will automatically update the view on the next digest. It is possible that your asynchronous code (the request) does not trigger a digest, in which case you will have to do it manually. There are many ways to do that: digest and apply
One simple way is to inject $timeout, and do a zero duration timeout (no time argument) with the sensitive code in the body of the function you pass in
Edit: so to answer your question more directly, you should be storing your data somewhere in your application when the call succeeds, and then rely on the angularjs digest loop to update your view. That's one of angulars big work saving features.
Use $route.reload(); method to reload entire page after your successful Transaction, be sure to add dependency injection '$route' in your Controller.

How to run code on a route that has access to services

I wonder what's the best way to configure a route which only purpose is to make use of a service call and then redirect.
I'm currently using this hack:
$routeProvider.when('/talks', {
template: '<div></div>',
controller: ['dateService', '$location', function(dateService, $location){
var nextTalk = dateService.getNextTalkDate();
$location.path('talks/' + nextTalk.format('MM') + '/' + nextTalk.format('YYYY'));
}]
});
Currently I set the controller configuration to an inline controller implementation which has dependencies on the services and then does it's thing and redirects.
However, it feels a bit weird, since I have to set template to some dummy value because otherwise the controller would not be invoked at all.
It feels as if I'm stressing the controller property for something it wasn't intended for.
I guess there should be a way to run some view unrelated code that has access to services on a route. I could right my own $routeProvider I guess but that seems to be a bit heavy for something I would consider should be built in.
Looks like '/talks' is a kinda abstract since its just used to redirect to other routes.. So how about setting up a route like this:
''/talks/:month/:year'
Where :month and :year is optional. If no month or year is given, your service returns a default talk. Which is probably the next talk. If params are given you just fetch the requested data.
So there's no redirect required. Now you specifiy the controller and the needed view and expose your data on the scope. Optionally would it be better to wrap your service call in a promise and resolve it at routeProviders resolve property.
This makes sure that the view only change if everything's resolved fine.
Hope that helps!
There's no way to inject services into anywhere into a route. Whether it be redirectTo or template, any code in there is handled on the module level. This means that the module is loaded first and then when the application has boostrapped itself then the services and injection-level code is executed. So the controller is your best bet (since that does support injection).
Controller is used in a lot of areas in AngularJS and it should work fine for what you're trying to do. You can either handle the redirection like you do in there or you can setup three different routes that point to the same controller (where you build the page).
var handler = { controller : 'Ctrl' };
$routeProvider.when('/talks', handler).
when('/talks/:month, handler).
when('/talks/:month/:year', handler);
And if you do end up using redirection, then just use $location.path(url).replace(). This will make the history stack jump back one level and therefore that the redirection triggering URL won't be in your history.

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