Develop Reference

AngularJS - How to cache service`s ajax result to reuse in controller

I was recomended to use Angular services in order to centralize many repetative functions that were store in my controller, so I am rewriting my code using services now.
It seemed simple at first but cant seem to find a good structure to fetch my ajax data (only once), then store it in my service for my controller to reuse the cached data when ever it needs it. At the moment I keep getting errors saying: TypeError: Cannot read property 'sayHello' of undefined.
I believe this is because theres is a delay to fetch my ajax data via my service before the controller loads. Im not quite certain how I can optimize this. Would anyone have a better stucture to this?
Service:
app.service('MyService', function ($http) {
this.sayHello = function () {
var deferred = $q.defer();
$http({
method: 'GET',
url: 'AJAX PATH',
headers: { "Accept": "application/json;odata=verbose;charset=utf-8"}
}).then(function(data){
var configurations = data;
var configurations.data_result_1 = configurations.data_result_1.split("\r\n");
var configurations.data_result_2 = configurations.data_result_2.split("\r\n");
deferred.resolve(configurations);
}
return deferred.promise;
};
this.sayHello(); //Run the function upon page laod.
});
Controller:
app.controller('AppController', function (MyService, $scope) {
$scope.configurations = null;
$scope.configurations = function() { MyService.sayHello() };
});

I recommend you to use another way to declare the service:
app.factory("MyService", function($http){
var configurations = {};
$http({
method: 'GET',
url: 'AJAX PATH',
headers: { "Accept": "application/json;odata=verbose;charset=utf-8"}
}).then(function(data){
configurations = data;
configurations.data_result_1 = configurations.data_result_1.split("\r\n");
configurations.data_result_2 = configurations.data_result_2.split("\r\n");
});
return {
getConfigurations: function(){
return configurations;
}
}
In your controller you can use a $watch, then when the configurations objects changes you take the information:
.controller("YourCtrl", function($scope,MyService){
var vm = this;
vm.configurations = {};
$scope.$watchCollection(function () { return MyService.getConfigurations()},function(newValue){
vm.configurations = newValue;
});

Totally agree with Bri4n about store configuration in the factory. Not agree about the controller because you said you don't want to watch, but only load data once.
But you $http already return a promise so as Brian said this is nice (just $q is useless here so you can delete it from injection). And I just wrapped http call in function, and the exposed function just check if configurations are already loaded. If yes, just return configurations else load it and then return it.
app.factory("MyService", function($http,$q){
var configurations = {};
function loadConfig(){
$http({
method: 'GET',
url: 'AJAX PATH',
headers: { "Accept": "application/json;odata=verbose;charset=utf-8"}
}).then(function(data){
configurations = data;
configurations.data_result_1 = configurations.data_result_1.split("\r\n");
configurations.data_result_2 = configurations.data_result_2.split("\r\n");
});
}
return {
getConfigurations: function(){
If( !!configurations ){
return configurations;
}
//Else loadConfig.then return configurations
}
}
In your controller you can just get config without need to know if it is already loaded.
.controller("YourCtrl", function(MyService){
var vm = this;
// If configurations already loaded return config, else load configurations and return configurations.
vm.configurations = MyService.getConfigurations();
I write on my phone so my code is not perfect I can't write properly.

OK, on second thought, it looks like you are not using the dependency array notation properly. Change your code to:
app.service('MyService', ['$http', function ($http) {
// do your stuff here
}]);
and for the controller:
app.controller('AppController', ['MyService', '$scope', function(MyService, $scope) {
// do your stuff here
}]);

AngularJS - Am I missing something in this Factory injection?

I'm using the $cacheFactory to save some data in my cache and everything was working very good until today that I've decided to separate my cacheFactory into a single class called MyFactory.js. Now I'm getting the error:
TypeError: tableCacheFactory is not a function
Because it's taking the injection as a simple method or something, does anybody know if I'm missing something here?
main.js
angular.module('main-component',
['my-component',
'my-cache-factory'
]);
MyFactory.js
angular.module('my-cache-factory', [])
.factory('tableCacheFactory', [
'$cacheFactory', function ($cacheFactory) {
return $cacheFactory('my-cache');
}
]);
MyService.js
angular.module('my-component', [])
.factory('my-component-service',
['$rootScope',
'$http',
'$q',
'tableCacheFactory',
function ($rootScope, $http, $q, tableCacheFactory) {
function getMyData (prodNro) {
var deferred = $q.defer();
var promise = deferred.promise;
var dataCache = tableCacheFactory.get('tablecache');
if (!dataCache) {
dataCache = tableCacheFactory('tablecache'); // TypeError: tableCacheFactory is not a function
}
var summaryFromCache = dataCache.get('tablecache' + prodNro);
if (summaryFromCache) {
deferred.resolve(summaryFromCache);
} else {
$http({
method: ...
data : ...
url: ...
}).success( function (data, status, headers, config) {
var objectResult = {
"data": data,
"status": status,
"headers": headers,
"config": config
}
if (data.response) {
// Save to cache
dataCache.put('tablecache'+prodNro, objectResult);
}
deferred.resolve(objectResult);
}).error(function (data, status, headers, config) {
...
});
}
return promise;
}

You seem to have some misconception about how the $cacheFactory works.
In var dataCache = tableCacheFactory.get('tablecache'); you are using it like it was a initialized Cache object containing another Cache object.
On the other hand dataCache = tableCacheFactory('tablecache'); uses it like it was the $cacheFactory itself.
And both of them try to access record 'tablecache' in something that I think should already be the tableCache itself.
The error is exactly what it says it is. As per the docs, calling $cacheFactory('my-cache'); does not return a function to create more caches.
It returns a $cacheFactory.Cache object which has methods like put(key, value) and get(key). Use those instead.
I'd change the whole structure of the caching (note that the name of the factory is changed):
.factory('tableCache', [
'$cacheFactory', function ($cacheFactory) {
//Return what the name of the factory implies
return $cacheFactory('tablecache');
}
]);
And then use that without needing to do more weird 'tablecache' namespacing
function getMyData (prodNro) {
...
var summaryFromCache = tableCache.get(prodNro);
...
tableCache.put(prodNro, objectResult);
}

The tableCacheFactory was wrapped inside my-cache-factory module. So you need to inject the module first into your my-component module before using it. So it should be like this:
angular.module('my-component', ['my-cache-factory'])

you defined your cache factory in the module my-cache-factory, but then never injected that module to your main component-service module. Do angular.module('my-component', ['my-cache-factory']) instead.

How to interrupt a series of $http calls in angularjs? [duplicate]

Given a Ajax request in AngularJS
$http.get("/backend/").success(callback);
what is the most effective way to cancel that request if another request is launched (same backend, different parameters for instance).

This feature was added to the 1.1.5 release via a timeout parameter:
var canceler = $q.defer();
$http.get('/someUrl', {timeout: canceler.promise}).success(successCallback);
// later...
canceler.resolve(); // Aborts the $http request if it isn't finished.

Cancelling Angular $http Ajax with the timeout property doesn't work in Angular 1.3.15.
For those that cannot wait for this to be fixed I'm sharing a jQuery Ajax solution wrapped in Angular.
The solution involves two services:
HttpService (a wrapper around the jQuery Ajax function);
PendingRequestsService (tracks the pending/open Ajax requests)
Here goes the PendingRequestsService service:
(function (angular) {
'use strict';
var app = angular.module('app');
app.service('PendingRequestsService', ["$log", function ($log) {
var $this = this;
var pending = [];
$this.add = function (request) {
pending.push(request);
};
$this.remove = function (request) {
pending = _.filter(pending, function (p) {
return p.url !== request;
});
};
$this.cancelAll = function () {
angular.forEach(pending, function (p) {
p.xhr.abort();
p.deferred.reject();
});
pending.length = 0;
};
}]);})(window.angular);
The HttpService service:
(function (angular) {
'use strict';
var app = angular.module('app');
app.service('HttpService', ['$http', '$q', "$log", 'PendingRequestsService', function ($http, $q, $log, pendingRequests) {
this.post = function (url, params) {
var deferred = $q.defer();
var xhr = $.ASI.callMethod({
url: url,
data: params,
error: function() {
$log.log("ajax error");
}
});
pendingRequests.add({
url: url,
xhr: xhr,
deferred: deferred
});
xhr.done(function (data, textStatus, jqXhr) {
deferred.resolve(data);
})
.fail(function (jqXhr, textStatus, errorThrown) {
deferred.reject(errorThrown);
}).always(function (dataOrjqXhr, textStatus, jqXhrErrorThrown) {
//Once a request has failed or succeeded, remove it from the pending list
pendingRequests.remove(url);
});
return deferred.promise;
}
}]);
})(window.angular);
Later in your service when you are loading data you would use the HttpService instead of $http:
(function (angular) {
angular.module('app').service('dataService', ["HttpService", function (httpService) {
this.getResources = function (params) {
return httpService.post('/serverMethod', { param: params });
};
}]);
})(window.angular);
Later in your code you would like to load the data:
(function (angular) {
var app = angular.module('app');
app.controller('YourController', ["DataService", "PendingRequestsService", function (httpService, pendingRequestsService) {
dataService
.getResources(params)
.then(function (data) {
// do stuff
});
...
// later that day cancel requests
pendingRequestsService.cancelAll();
}]);
})(window.angular);

Cancelation of requests issued with $http is not supported with the current version of AngularJS. There is a pull request opened to add this capability but this PR wasn't reviewed yet so it is not clear if its going to make it into AngularJS core.

If you want to cancel pending requests on stateChangeStart with ui-router, you can use something like this:
// in service
var deferred = $q.defer();
var scope = this;
$http.get(URL, {timeout : deferred.promise, cancel : deferred}).success(function(data){
//do something
deferred.resolve(dataUsage);
}).error(function(){
deferred.reject();
});
return deferred.promise;
// in UIrouter config
$rootScope.$on('$stateChangeStart', function (event, toState, toParams, fromState, fromParams) {
//To cancel pending request when change state
angular.forEach($http.pendingRequests, function(request) {
if (request.cancel && request.timeout) {
request.cancel.resolve();
}
});
});

For some reason config.timeout doesn't work for me. I used this approach:
let cancelRequest = $q.defer();
let cancelPromise = cancelRequest.promise;
let httpPromise = $http.get(...);
$q.race({ cancelPromise, httpPromise })
.then(function (result) {
...
});
And cancelRequest.resolve() to cancel. Actually it doesn't not cancel a request but you don't get unnecessary response at least.
Hope this helps.

This enhances the accepted answer by decorating the $http service with an abort method as follows ...
'use strict';
angular.module('admin')
.config(["$provide", function ($provide) {
$provide.decorator('$http', ["$delegate", "$q", function ($delegate, $q) {
var getFn = $delegate.get;
var cancelerMap = {};
function getCancelerKey(method, url) {
var formattedMethod = method.toLowerCase();
var formattedUrl = encodeURI(url).toLowerCase().split("?")[0];
return formattedMethod + "~" + formattedUrl;
}
$delegate.get = function () {
var cancelerKey, canceler, method;
var args = [].slice.call(arguments);
var url = args[0];
var config = args[1] || {};
if (config.timeout == null) {
method = "GET";
cancelerKey = getCancelerKey(method, url);
canceler = $q.defer();
cancelerMap[cancelerKey] = canceler;
config.timeout = canceler.promise;
args[1] = config;
}
return getFn.apply(null, args);
};
$delegate.abort = function (request) {
console.log("aborting");
var cancelerKey, canceler;
cancelerKey = getCancelerKey(request.method, request.url);
canceler = cancelerMap[cancelerKey];
if (canceler != null) {
console.log("aborting", cancelerKey);
if (request.timeout != null && typeof request.timeout !== "number") {
canceler.resolve();
delete cancelerMap[cancelerKey];
}
}
};
return $delegate;
}]);
}]);
WHAT IS THIS CODE DOING?
To cancel a request a "promise" timeout must be set.
If no timeout is set on the HTTP request then the code adds a "promise" timeout.
(If a timeout is set already then nothing is changed).
However, to resolve the promise we need a handle on the "deferred".
We thus use a map so we can retrieve the "deferred" later.
When we call the abort method, the "deferred" is retrieved from the map and then we call the resolve method to cancel the http request.
Hope this helps someone.
LIMITATIONS
Currently this only works for $http.get but you can add code for $http.post and so on
HOW TO USE ...
You can then use it, for example, on state change, as follows ...
rootScope.$on('$stateChangeStart', function (event, toState, toParams) {
angular.forEach($http.pendingRequests, function (request) {
$http.abort(request);
});
});

here is a version that handles multiple requests, also checks for cancelled status in callback to suppress errors in error block. (in Typescript)
controller level:
requests = new Map<string, ng.IDeferred<{}>>();
in my http get:
getSomething(): void {
let url = '/api/someaction';
this.cancel(url); // cancel if this url is in progress
var req = this.$q.defer();
this.requests.set(url, req);
let config: ng.IRequestShortcutConfig = {
params: { id: someId}
, timeout: req.promise // <--- promise to trigger cancellation
};
this.$http.post(url, this.getPayload(), config).then(
promiseValue => this.updateEditor(promiseValue.data as IEditor),
reason => {
// if legitimate exception, show error in UI
if (!this.isCancelled(req)) {
this.showError(url, reason)
}
},
).finally(() => { });
}
helper methods
cancel(url: string) {
this.requests.forEach((req,key) => {
if (key == url)
req.resolve('cancelled');
});
this.requests.delete(url);
}
isCancelled(req: ng.IDeferred<{}>) {
var p = req.promise as any; // as any because typings are missing $$state
return p.$$state && p.$$state.value == 'cancelled';
}
now looking at the network tab, i see that it works beatuifully. i called the method 4 times and only the last one went through.

You can add a custom function to the $http service using a "decorator" that would add the abort() function to your promises.
Here's some working code:
app.config(function($provide) {
$provide.decorator('$http', function $logDecorator($delegate, $q) {
$delegate.with_abort = function(options) {
let abort_defer = $q.defer();
let new_options = angular.copy(options);
new_options.timeout = abort_defer.promise;
let do_throw_error = false;
let http_promise = $delegate(new_options).then(
response => response,
error => {
if(do_throw_error) return $q.reject(error);
return $q(() => null); // prevent promise chain propagation
});
let real_then = http_promise.then;
let then_function = function () {
return mod_promise(real_then.apply(this, arguments));
};
function mod_promise(promise) {
promise.then = then_function;
promise.abort = (do_throw_error_param = false) => {
do_throw_error = do_throw_error_param;
abort_defer.resolve();
};
return promise;
}
return mod_promise(http_promise);
}
return $delegate;
});
});
This code uses angularjs's decorator functionality to add a with_abort() function to the $http service.
with_abort() uses $http timeout option that allows you to abort an http request.
The returned promise is modified to include an abort() function. It also has code to make sure that the abort() works even if you chain promises.
Here is an example of how you would use it:
// your original code
$http({ method: 'GET', url: '/names' }).then(names => {
do_something(names));
});
// new code with ability to abort
var promise = $http.with_abort({ method: 'GET', url: '/names' }).then(
function(names) {
do_something(names));
});
promise.abort(); // if you want to abort
By default when you call abort() the request gets canceled and none of the promise handlers run.
If you want your error handlers to be called pass true to abort(true).
In your error handler you can check if the "error" was due to an "abort" by checking the xhrStatus property. Here's an example:
var promise = $http.with_abort({ method: 'GET', url: '/names' }).then(
function(names) {
do_something(names));
},
function(error) {
if (er.xhrStatus === "abort") return;
});

AngularJS call common controller function from outside controller

My basic premise is I want to call back to the server to get the logged in user in case someone comes to the site and is still logged in. On the page I want to call this method. Since I am passing the user service to all my controllers I don't know which controller will be in use since I won't know what page they're landing on.
I have the following User Service
app.factory('userService', function ($window) {
var root = {};
root.get_current_user = function(http){
var config = {
params: {}
};
http.post("/api/user/show", null, config)
.success(function(data, status, headers, config) {
if(data.success == true) {
user = data.user;
show_authenticated();
}
});
};
return root;
});
Here is an empty controller I'm trying to inject the service into
app.controller('myResourcesController', function($scope, $http, userService) {
});
So on the top of my index file I want to have something along the lines of
controller.get_current_user();
This will be called from all the pages though so I'm not sure the syntax here. All examples I found related to calling a specific controller, and usually from within another controller. Perhaps this needs to go into my angularjs somewhere and not simply within a script tag on my index page.

You could run factory initialization in run method of your angular application.
https://docs.angularjs.org/guide/module#module-loading-dependencies
E.g.
app.run(['userService', function(userService) {
userService.get_current_user();
}]);
And userService factory should store authenticated user object internaly.
...
if (data.success == true) {
root.user = data.user;
}
...
Then you will be able to use your factory in any controller
app.controller('myController', ['userService', function(userService) {
//alert(userService.user);
}]);

You need to inject $http through the factory constructor function, for firsts
app.factory('userService', function ($window, $http) {
var root = {};
root.get_current_user = function(){
var config = {
params: {}
};
$http.post("/api/user/show", null, config)
.success(function(data, status, headers, config) {
if(data.success == true) {
user = data.user;
show_authenticated();
}
});
};
return root;
});
in your controller you can say
$scope.get_current_user = UserService.get_current_user();
ng attributes in your html if needed. besides this, i am not sure what you need.

Why im not getting the response back from this factory function in angularJS [duplicate]

This question already has answers here:
How do I return the response from an asynchronous call?
(41 answers)
Closed 8 years ago.
I got this angular factory:
var productApp = angular.module('productApp', ['ngRoute', 'LocalStorageModule', 'angularSlideables', 'ui.bootstrap']);
productApp.factory('productFactory', function($http, localStorageService, $q) {
var factory = {};
factory.getProductById = function(prod_id) {
if(prod_id !== '') {
$http({
url: 'rest/message/getProductById/' + prod_id,
method: 'GET'
}).success(function(data, status) {
return data;
}).error(function(data, status){
// do nothing
});
}else {
alert("There was an error while passing the ID. Please refresh the page and try again");
}
}
return factory;
});
Injecting the factory in a controller and calling to the "getProductById" function:
productApp.controller('ModalInstanceCtrl', function ($scope, $modalInstance, productFactory, prodId) {
console.log("this is the prod id " + prodId);
// search product in the database
$scope.prod = productFactory.getProductById(prodId);
console.log($scope.prod);
$scope.ok = function () {
console.log($scope.prodData);
};
$scope.cancel = function () {
$modalInstance.dismiss('cancel');
};
});
Now, don't know what's wrong with it... the function RETURNS the data because i did a console.log(data) and saw all the response, but in the controller if i inspect the $scope.prod, it's undefined. It's not returning the data back from the function.
(Just in case you guys ask, the "prodId" in the controller parameter is fine, and retrieving that from another controller)
How can i solve this? :(
Thanks in advance.

The pattern I have used to solve this problem is to pass in the success & error callback functions to the factory... like this:
var productApp = angular.module('productApp', ['ngRoute', 'LocalStorageModule', 'angularSlideables', 'ui.bootstrap']);
productApp.factory('productFactory', function($http, localStorageService, $q) {
var factory = {};
factory.getProductById = function(prod_id, successCallback, errorCallback) {
if(prod_id !== '') {
$http({
url: 'rest/message/getProductById/' + prod_id,
method: 'GET'
})
.success(successCallback)
.error(errroCallback);
} else {
alert("There was an error while passing the ID. Please refresh the page and try again");
}
}
return factory;
});
and then:
productApp.controller('ModalInstanceCtrl', function ($scope, $modalInstance, productFactory, prodId) {
console.log("this is the prod id " + prodId);
// search product in the database
productFactory.getProductById(prodId, function successCallback(data) {
$scope.prod = data;
}, function errorCallback(data, status) {
alert("An error occurred retrieving product. Please refresh the page & try again.");
});
console.log($scope.prod);
$scope.ok = function () {
console.log($scope.prodData);
};
$scope.cancel = function () {
$modalInstance.dismiss('cancel');
};
});
By doing it this way instead, you have access to the scope in the controller & can do whatever you need to with the returned data.

Here's what I do. I'm using $resournce instead of $http, but it should be enough to get you going. You may even want to use the $resource since it has the built in fns.
My factory:
.factory('WorkOrder', function($resource){
// $resource Usage: $resource(url[, paramDefaults][, actions]);
return $resource('/controller/get/:id.json', {}, {
/*
* By default, the following actions are returned; modify or add as needed
* { 'get': {method:'GET'},
* 'save': {method:'POST'},
* 'query': {method:'GET', isArray:true},
* 'delete': {method:'DELETE'} };
*/
});
})
My controller:
// get the work order data using the work order id from the tag attribute
var getWO = function() {
WorkOrder.get({woId:$attrs.id},
// success callback
function(response) {
// Assign the work order data to the scope
$scope.WorkOrder = response.WorkOrder;
},
// fail callback
function(response) {
// whatever...
}
);
};
getWO();
I put my success and fail fns in my controller because that's where I most likely know how I want to respond to success or failed calls. I also assign the function to a variable and then call it right after in case I want to include the fn call inside a $timeout or call it elsewhere.
Hope this answers your question.