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manual bootstrap angular with http calls

I have a WebAPI service that returns dynamic configuration data. Before my angular app loads I would like to call that service and load the config data into angular. JSFiddle of my attempt at doing that. My question is, after seeing the string test in the console I am seeing nothing else written into the console. How do I get test 2 and wierd wierd to appear into the console
var app = angular.module('app', [])
app.provider("ConfigService", function () {
var self = this;
self.Settings = {};
self.config = function (data) {
console.log(data);
};
this.$get =
function($http) {
return self;
};
});
angular.element(document).ready(function($http) {
console.log('test')
angular.module('app').config([
'ConfigServiceProvider',
function(configService) {
console.log('test 2')
$http.get('http://www.google.com').then(function(result) {
console.log('wierd wierd')
configService.config(result);
angular.bootstrap(document, ['app']);
})
}
]);
});
EDIT
In response to the question, why I do not run this in app.run phase instead.
In the app.run phase the app is still initializing and sometimes it loads up prior to my configuration section being completed. I wanted 100% guarantee that my config section is loaded first before any of the app is.

You can use $http outside of your angular module with angular.injector. With $http you can request the config from your server and bootstrap your app when $http's promise resolves.
JS Fiddle
Create module
var app = angular.module("app", []);
app.provider("configService", function () {
var configService = {
config: {}
};
this.setConfig = function (config) { configService.config = config; };
this.$get = function() { return configService; };
});
Function that fetches config from server
function fetchConfig() {
var $http = angular.injector(["ng"]).get("$http");
return $http.get("http://www.google.com");
}
Function that bootstraps app
function bootstrap(config) {
app.config(["configServiceProvider", function (configServiceProvider) {
configServiceProvider.setConfig(config);
}]).run(["configService", function (configService) {
//Not necessary, just to confirm everything worked
console.log("YAY! You have a config:", configService.config);
}]);
angular.bootstrap(document, ["app"])
}
Put it all together!
fetchConfig().then(
/*sucess*/function (config) { angular.element(document).ready(function () { bootstrap(config); }); },
/*fail*/ function (err) { console.log("UH OH could not retrieve config!", err); });

EDIT: Please use #StevenWexler 's answer: https://stackoverflow.com/a/37599857/5670592. It is much more correct, uses a nifty angular feature ($inject), and will provide configuration before the beginning of the bootstrap cycle.
I have updated the application with your constraints regarding blocking execution until API call is complete.
Try this: https://jsfiddle.net/6svnemu8/3/
I moved the code to the module.run(...) block. This is where all providers are available and you can use $http and your ConfigService. I kept the bootstrap call in the document ready function, and I also added the $q service so you can block execution of the application until the API call is complete. You can verify this by looking at the order of the test outputs in the console:
angular.module('app').run([
'ConfigService', '$http', '$q',
function(configService, $http, $q) {
console.log('test 2');
var deferred = $q.defer();
$http.get('/6svnemu8/2/').then(function(result) {
deferred.resolve(result);
}, function(result){
deferred.reject(result);
});
console.log("test 3");
deferred.promise.then(function(result){
console.log('wierd wierd');
configService.config(result);
}, function(result){
console.log("call failed.");
});
}
]);

Option 1 -- if you have an MVC app
In your main razor view, use JSON.Net to serialize your Model (or a property on it) to JavaScript.
<script>
window.configuration = #(Html.Raw(JsonConvert.SerializeObject(Model)))
</script>
Then put it into an angular constant so you can inject it anywhere you need it, and it's guaranteed to be there. This is the most convenient way to do it.
angular.module('YourModule').constant('configuration', window.configuration);
Option 2 -- loading it asynchronously
This service will load the configuration and cache the promise.
angular.module('YourModule').factory('configuration', ['$http', function($http) {
var configurationLoaded;
var service = {
get: get
};
function get() {
if(configurationLoaded) return configurationLoaded;
configurationLoaded = $http.get( ... );
return configurationLoaded;
}
return service;
}]);
Then anywhere you need it, you'll have to pull out properties from it like this:
angular.module('YourModule').controller('SomeController', ['configuration', function(configuration) {
var vm = this;
configuration.get().then(function(config) {
vm.someSetting = config.someSetting;
});
}]);

How store $http get response in variable accesible from outside $http function (Angularjs)?

I'm still learning angular and javascript and I find stack
overflow really helpful. Actually this is first time I couldn't find solution to my problem in other questions & answers here. I tried many solutions, but nothing is working for me.
In short: I want to save response from $http get (user data) in variable, so I could use it in other functions in this controller.
My factory with $http get function:
app.factory('getUserFactory', ['$http', function($http){
return {
getUserData : function(email, password) {
return $http.get('https://xxxxxxx.xxx.xx/api/v1/user/', {
headers: {
"Authorization": 'Basic '+ window.btoa(email +':'+password)
}
});
}
};
}]);
My controller with functions:
app.controller('UserController', ['$scope','$http', 'getUserFactory', function($scope, $http, getUserFactory) {
var user= {}; //Used to bind input fields from html file
$scope.user= user;
$scope.userData = {}; // <-- HERE I WANT TO STORE RESPONSE
$scope.logIn = function() { // function runs on click
getUserFactory.getUserData(user.email, user.password).success(function(response){
$scope.userData = response.objects[0];
});
};
And simple on click function I use to test if it's working:
$scope.consoleLog = function () {
console.log($scope.userData);
};
I assume my problem is connected with asynchrony of javascript, but I always call $http get first (user clicks 'log in' button) and then I try to use response to display user details. But outside $scope.logIn(), $scope.userData becomes an empty object again.

I assume you are calling login method in onclick.just try this:;
$scope.logIn = function() { // function runs on click
getUserFactory.getUserData(user.email, user.password).then(function(response){
$scope.userData = response.objects[0];
});
};

How to persist data in a service on refresh in AngularJS?

I'm creating a new multi-use website for a new brand my company is launching in a few weeks. We use a WordPress backend and via the WP REST API, are now able to uncouple the system and use NodeJS/Express/AngularJS for our front end and middleware applications.
Currently, when I load the landing page, an HTTP GET Request is made to WordPress for all of the relevant posts for our front page. This data is then passed to a service to be used across controllers.
So, the initial set up is this:
landingController
angular
.module('glossy')
.controller('LandingController', LandingController)
LandingController.$inject = ['featuredService', 'sharedPostsService'];
function LandingController(featuredService, sharedPostsService){
// Set up view model (vm) variables
var vm = this;
vm.featured = [];
// Call this function on state 'home' load
activate();
// Calls getFeatured function and prints to console
function activate(){
return getFeatured()
.then(function(){
console.log('GET Featured Posts');
});
}
// Calls the featuredService then stores response clientside for rendering
function getFeatured(){
return featuredService.getFeatured()
.then(function(data){
vm.featured = data;
sharedPostsService.setPosts(data);
return vm.featured;
});
}
}
Factory for HTTP Request
angular
.module('glossy')
.factory('featuredService', featuredService)
featuredService.$inject = ['$http'];
function featuredService($http){
return {
getFeatured: getFeatured
};
// Performs HTTP request then calls success or error functions
function getFeatured(){
return $http.get('/api/posts')
.then(getFeaturedComplete)
.catch(getFeaturedFailed);
// Returns response data
function getFeaturedComplete(response){
return response.data;
}
// Prints error to console
function getFeaturedFailed(error) {
console.log('HTTP Request Failed for getFeatured: ' + error.data);
}
}
}
Service that holds data from factory
angular
.module('glossy')
.factory('sharedPostsService', sharedPostsService)
function sharedPostsService(){
var listPosts = [];
return {
setPosts: function(posts){
listPosts = posts;
},
getPosts: function(){
return listPosts;
}
};
}
Now, when a user clicks on a post on the landing page, she is taken to a page that displays on the article that she clicked on, which works. However, if she refreshes this page, all the data is gone. Calling the service results in an empty object.
Post controller
angular
.module('glossy')
.controller('PostController', PostController)
PostController.$inject = ['$window', '$filter', '$stateParams', 'sharedPostsService'];
function PostController($window, $filter, $stateParams, sharedPostsService){
var vm = this;
vm.postsList = sharedPostsService.getPosts();
vm.postTitle = $stateParams.title;
vm.thisPost = filterPosts();
function filterPosts() {
return $filter('filter')(vm.postsList, vm.postTitle);
};
}
How do I set this up to ensure that the data persists through refresh? I looked into using localStorage but everything I found said it involved stringifying data and storing it in key value pairs?
Any help is appreciated.

You cannot use a service to persist data on a page refresh.
If the data is large use a database, else use sessionStorage or localStorage.
Storing the data:
window.localStorage['data'] = JSON.stringify(data);
Retrieving the data:
return angular.fromJson(window.localStorage['data']);

Angular - Best practice for retrieving data from a Factory method

I'm looking for some information on the best way to retrieve data from a local JSON file and handle the response. After browsing through Stack Overflow, I have some mixed thoughts as I've seen multiple ways of doing the same thing (although no explanation on why one may or may not be preferred).
Essentially, I have an Angular app that is utilising a factory to retrieve data from a JSON file; I'm then waiting for the response to resolve in my controller before using it in my html file, similar to the below:
Option 1
Factory:
comparison.factory('Info', ['$http', function($http) {
var retrievalFile = 'retrievalFile.json';
return {
retrieveInfo: function() {
return $http.get(retrievalFile);
}
}
}]);
Controller:
comparison.controller('comparisonController', ['$scope', 'Info', function($scope, Info) {
Info.retrieveInfo().then(function(response) {
$scope.info = response.data;
});
}]);
My main point of contention is figuring out when it's best to wait for the response to resolve, or if it even matters. I'm toying with the idea of having the factory return the fulfilled promise, and wait for the controller to retrieve the data also. In my view, it's best to abstract all data retrieval out of the controller and into the factory, but I'm not sure if this extends to waiting for the actual data to be returned within the factory itself. With this in mind, I'm confused about whether to opt for option 1 or option 2 and would really appreciate some feedback from more experienced/qualified developers!
Option 2
Factory:
comparison.factory('Info', ['$http', function($http) {
var retrievalFile = 'retrievalFile.json';
return {
retrieveInfo: function() {
return $http.get(retrievalFile).then(function(response) {
return response.data;
});
}
}
}]);
Controller:
comparison.controller('comparisonController', ['$scope', 'Info', function($scope, Info) {
Info.retrieveInfo().then(function(response) {
$scope.info = response;
});
}]);
Thank you for any input/suggestions in advance!

It depends on what your controller is expecting and how you set up your application. Generally, I always go with the second option. Its because I usually have global error or success handlers in all api requests and I have a shared api service. Something like below.
var app = angular.module('app', []);
app.service('ApiService', ['$http', function($http) {
var get = function(url, params) {
$http.get(url, { params: params })
.then(handleSuccess, handleError);
};
// handle your global errors here
// implementation will vary based upon how you handle error
var handleError = function(response) {
return $q.reject(response);
};
// handle your success here
// you can return response.data or response based upon what you want
var handleSuccess = function(response) {
return response.data;
};
}]);
app.service('InfoService', ['ApiService', function(ApiService) {
var retrieveInfo = function() {
return ApiService.get(retrievalFile);
/**
// or return custom object that your controller is expecting
return ApiService.get.then(function(data) {
return new Person(data);
});
**//
};
// I prefer returning public functions this way
// as I can just scroll down to the bottom of service
// to see all public functions at one place rather than
// to scroll through the large file
return { retrieveInfo: retrieveInfo };
}]);
app.controller('InfoController', ['InfoService', function(InfoService) {
InfoService.retrieveInfo().then(function(info) {
$scope.info = info;
});
}])
Or if you are using router you can resolve the data into the controller. Both ngRouter and uiRouter support resolves:
$stateProvider.state({
name: 'info',
url: '/info',
controller: 'InfoController',
template: 'some template',
resolve: {
// this injects a variable called info in your controller
// with a resolved promise that you return here
info: ['InfoService', function(InfoService) {
return InfoService.retrieveInfo();
}]
}
});
// and your controller will be like
// much cleaner right
app.controller('InfoController', ['info', function(info) {
$scope.info = info;
}]);

It's really just preference. I like to think of it in terms of API. What is the API you want to expose? Do you want your controller to receive the entire response or do you want your controller to just have the data the response wraps? If you're only ever going to use response.data then option 2 works great as you never have to deal with anything but the data you're interested in.
A good example is the app we just wrote where I work. We have two apps: a back-end API and our front-end Angular application. We created an API wrapper service in the front-end application. In the service itself we place a .catch for any of the API endpoints that have documented error codes (we used Swagger to document and define our API). In that .catch we handle those error codes and return a proper error. When our controllers/directives consume the service they get back a much stricter set of data. If an error occurs then the UI is usually safe to just display the error message sent from the wrapper service and won't have to worry about looking at error codes.
Likewise for successful responses we do much of what you're doing in option 2. In many cases we refine the data down to what is minimally useful in the actual app. In this way we keep a lot of the data churning and formatting in the service and the rest of the app has a lot less to do. For instance, if we need to create an object based on that data we'll just do that in return the object to the promise chain so that controllers aren't doing that all over the place.

I would choose option two, as it your options are really mostly the same. But let see when we add a model structure like a Person suppose.
comparison.factory('Info', ['$http', function($http) {
var retrievalFile = 'retrievalFile.json';
return {
retrieveInfo: function() {
return $http.get(retrievalFile).then(function(response) {
//we will return a Person...
var data = response.data;
return new Person(data.name, data.age, data.gender);
});
}
}
}]);
This is really simple, but if you have to map more complex data into object models (you retrieve a list of people with their own items... etc), that's when things get more complicated, you will probably want to add a service to handle the mapping between data and models. Well you have another service DataMapper(example), if you choose your first option you will have to inject DataMapper into your controller and you will have to make your request through your factory, and map the response with the injected service. And then you probably say, Should I have all this code here? ... Well probably no.
That is an hypothetical case, something that count a lot is how you feel structuring your code, won't architecture it in a way you won't understand. And at the end take a look at this: https://en.wikipedia.org/wiki/SOLID_(object-oriented_design) and research more information about this principles but focused to javascript.

Good question. A couple of points:
Controllers should be view centric versus data centric therefore you
want remove data logic from the controller and rather have it focus
on business logic.
Models (M in MVC) are a data representation of your application and
will house the data logic. In Angular case this would be a service
or factory class as you rightfully pointed out. Why is that well for
example:
2.1 AccountsController (might have multiple data models injected)
2.1.1 UserModel
2.1.2 AuthModel
2.1.3 SubscriptionModel
2.1.4 SettingsModel
There are numerous ways to approach the data model approach, but I would say your service class should be the data REST model i.e. getting, storing, caching, validating, etc. I've included a basic example, but suggest you investigate JavaScript OOP as that will help point you in the right direction as to how to build data models, collections, etc.
Below is an example of service class to manage your data.Note I have not tested this code but it should give you a start.
EXAMPLE:
(function () {
'use strict';
ArticleController.$inject = ['$scope', 'Article'];
function ArticleController($scope, Article) {
var vm = this,
getArticles = function () {
return Article.getArticles()
.then(function (result) {
if (result) {
return vm.articles = result;
}
});
};
vm.getArticles = getArticles;
vm.articles = {};
// OR replace vm.articles with $scope if you prefer e.g.
$scope.articles = {};
$scope.userNgClickToInit = function () {
vm.getArticles();
};
// OR an init on document ready
// BUT to honest I would put all init logic in service class so all in calling is init in ctrl and model does the rest
function initArticles() {
vm.getArticles();
// OR chain
vm.getArticles()
.then(getCategories); // doesn't here, just an example
}
initArticles();
}
ArticleModel.$inject = ['$scope', '$http', '$q'];
function ArticleModel($scope, $http, $q) {
var model = this,
URLS = {
FETCH: 'data/articles.json'
},
articles;
function extract(result) {
return result.data;
}
function cacheArticles(result) {
articles = extract(result);
return articles;
}
function findArticle(id) {
return _.find(articles, function (article) {
return article.id === parseInt(id, 10);
})
}
model.getArticles = function () {
return (articles) ? $q.when(articles) : $http.get(URLS.FETCH).then(cacheArticles);
};
model.getArticleById = function (id) {
var deferred = $q.defer();
if (articles) {
deferred.resolve(findArticle(id))
} else {
model.getBookmarks().then(function () {
deferred.resolve(findArticle(id))
})
}
return deferred.promise;
};
model.createArticle = function (article) {
article.id = articles.length;
articles.push(article);
};
model.updateArticle = function (bookmark) {
var index = _.findIndex(articles, function (a) {
return a.id == article.id
});
articles[index] = article;
};
model.deleteArticle = function (article) {
_.remove(articles, function (a) {
return a.id == article.id;
});
};
}
angular.module('app.article.model', [])
.controller('ArticleController', ArticleController)
.service('Article', ArticleModel);
})()

how to load config file to an angular Object

I have a simple config page set up on my nodeJS server.
4 inputfields to store some IPs.
those fields are bound to
var formApp = angular.module('formApp', [])
.controller('formController', function($scope) {
$scope.formData = {};
loadConfig();
$scope.$watchCollection('formData',function() {
saveConfig($scope);
});
});
Every change in the model calls the saveConfig(), which saves the config on the server:
function saveConfig($scope) {
socket.emit('save_config', {config: $scope.formData});
}
This seems to work. The Server correctly prints the content of the received object and there is no error in the saving process.
Now i want to LOAD the config into the angular Model, everytime the page is opened.
loadConfig() tells the server to load the config.json, parse it, and send it to the browser:
socket.on('load_config', function(data) {
console.log("[INFO] Config received:");
angular.element(document.getElementById('config')).scope().formData = data;
});
but it doesn't seem to work.. on page refresh, all the fields are empty.
besides, $scope.formData = {}; empties the object, so the config is immediately overwritten. how can i prevent this? (i don't know if this is actually the whole problem)
Is there anything terribly wrong with my approach?
Thanks
UPDATE:
It seems not to be completely wrong...
on refresh, the inputs are empty, but if i start typing and console.log the formData Object, it seems to have loaded the values in a weird, nested way
{"config":{"config":{"config":{"config":{},"ip2":"tzfrzftztrf","ip3":"ztu6tzzt6"},"ip2":"hhhkkizbi"},"ip2":"hhkkkkööö"},"ip3":"h"}
this was 4 refreshes. So it seems to work somehow, but not load it correctly

You can create service for loading configuration and inject it you module like
var formApp = angular.module('formApp', [])
formApp.service('LoadConfigService', function($http) {
return({
loadConfig: function() {
var promise = $http.get('config.json').then(function (response) {
return response.data;
});
return promise;
}});
});
.controller('formController', function($scope,LoadConfigService) {
$scope.formData = {};
LoadConfigService.loadConfig().then(function(data) {
//Action After response
});
$scope.$watchCollection('formData',function() {
saveConfig($scope);
});
});