I am trying to implement a faceted search based on AngularJS https://github.com/kmaida/angular-faceted-search
As the example is based on a dataset incorporated in the JS, I am trying to load the JSON File remotely. (total noob in angularJS by the way).
In the example, the Controller is defiend as:
myApp.controller('MainCtrl', function($scope, Helpers) {
And there are 2 helpers defined
myApp.factory('Helpers', function() {...
I am trying to inject the $http in a third helper, my code:
,
//below line 30 in https://github.com/kmaida/angular-faceted-search/blob/master/app.js
fetchData: function (){
var resultjson=[]
$http.get('/api/data.json').success(function(data) {
resultjson=data
console.log(data);
});
console.log(resultjson);
return resultjson;
}
The newly defined variable resultjson has a value in the success function, but no value beyond that point.
Any one can help me fetch the data correctly? Appreciate the support.
If you want to receive data from $http, you will have to use promises. Right now, you are returning resultjson before the value has been received from the api end point.
You should return promise, and once the promise is resolved, the value will be in the promise.
Due to the fact, that $http returns promise, you can return it directly, without wrapping it in another promise.
fetchData: function (){
return $http.get('/api/data.json');
}
and you can access the data in your your controller and assign to the scope:
Helpers.fetchData().then(function(data){
$scope.items = data.data;
})
Related
I have a method in my angular 1.5 controller, as shown below but I wanted to refactor the ajax call into the factory itself but I'm having problems with promises.. I'm trying to get to a point where in my controller I can just call the method like I've shown below. Is this possible? I'm trying to avoid having the ...success(function(...) in the controller code.
Any help much appreciated.
Trying to move to
vm.member = someFactory.getMember(vm.id);
Existing working controller code
vm.myMethod = myMethod;
...
function myMethod() {
someFactory.getMember(vm.id).success(function(response) {
vm.member = response;
});
}
When I move the getMethod line into the factory the response is populated obviously but as soon as I come back to the controller, even with the return value from the factory being the response the result is undefined. I know this is because of promises but is there a design pattern I'm missing or a clean way of doing this. Using my currently approach my controller is littered with .success(function()...)
Many thanks!
The procedure is called promise unwrapping.
Besides the fact that success is deprecated and should be replaced with then,
someFactory.getMember(vm.id).then(function(response) {
var data = res.data;
...
});
it is totally ok to have this in controller.
The alternative to this pattern is to return self-filling object (something that ngResource $resource does):
function getMember(...) {
var data = {};
$http(...).then(function (response) {
// considering that response data is JSON object,
// it can replace existing data object
angular.copy(data, response.data);
});
return data;
}
In this case controller can get a reference to the object instantly, and the bindings of object properties {{ vm.member.someProperty }} will be updated in view on response.
The pattern is limited to objects (and arrays), scalar values should be wrapped with objects.
I am trying to give access to a json file that contains config information for my project (things like rev number, project name, primary contact, etc) I created a factory that retrieves the json file using http.get, I can then pull that data into my controller but I am unable to access it from anywhere in the controller.
I did not write the factory, I found it as an answer to another person's question and it is copied almost entirely so if it not the right way to accomplish what I am trying to do please correct me.
here is the factory:
app.factory('configFactory', ["$http", function($http) {
var configFactory = {
async: function() {
// $http returns a promise, which has a then function, which also returns a promise
var promise = $http.get('assets/json/config.json').then(function(response) {
// The then function here is an opportunity to modify the response
console.log(response.data.config);
// The return value gets picked up by the then in the controller.
return response.data.config;
});
// Return the promise to the controller
return promise;
}
};
return configFactory;
}]);
and here is my controller:
app.controller('footerController', ['$scope', '$rootScope', 'configFactory', function footerController($scope, $rootScope, configFactory) {
var body = angular.element(window.document.body);
$scope.onChange = function(state) {
body.toggleClass('light');
};
configFactory.async().then(function(d) {
$scope.data = d;
// this console log prints out the data that I am trying to access
console.log($scope.data);
});
// this one prints out undefined
console.log($scope.data);
}]);
So essentially I have access to the data within the function used to retrieve it but not outside of that. I can solve this with rootScope but I am trying to avoid that because I think its a bandaid and not a proper solution.
Any help would be great but this is my first experience with http.get and promises and all that stuff so a detailed explanation would be very much appreciated.
[EDIT 1] The variables from the config file will need to be manipulated within the web app, so I can't use constants.
Don't assign your response data to scope variable , create a property in your factory itself and assign the response to this property in your controller when your promise gets resolved.This way you will get the value in all the other controllers.
I have updated your factory and controller like below
app.factory('configFactory', ["$http", function($http) {
var configFactory = {
async: function() {
// $http returns a promise, which has a then function, which also returns a promise
var promise = $http.get('assets/json/config.json').then(function(response) {
// The then function here is an opportunity to modify the response
console.log(response.data.config);
// The return value gets picked up by the then in the controller.
return response.data.config;
});
// Return the promise to the controller
return promise;
},
config:'' // new proprety added
};
return configFactory;
}]);
app.controller('footerController', ['$scope', '$rootScope', 'configFactory', function footerController($scope, $rootScope, configFactory) {
var body = angular.element(window.document.body);
$scope.onChange = function(state) {
body.toggleClass('light');
};
configFactory.async().then(function(d) {
// $scope.data = d;
configFactory.config=d;
// this console log prints out the data that I am trying to access
console.log($scope.data);
});
// this one prints out undefined
console.log($scope.data);
}]);
Have you looked into using angular constants? http://ilikekillnerds.com/2014/11/constants-values-global-variables-in-angularjs-the-right-way/ You can leverage them as global variables accessible from any controller without the ramifications of assigning the values to rootScope
I've been facing a trouble while working with Factory/Service. I've created an AjaxRequests factory for all of my AJAX calls. My factory code is
.factory('AjaxRequests', ['$http', function ($http) {
return {
getCampaignsData: function () {
var campaigns
return $http.get(url).then(function (response) {
campaigns = response.data;
return campaigns;
});
}
}
}])
I've created another service in which I am injecting this factory. My service code
.service('CampaignsService', ['$rootScope', 'AjaxRequests', function ($rootScope, AjaxRequests) {
this.init = function () {
this.camps;
AjaxRequests.getCampaignsData().then(function (response) {
this.camps = response.campaigns;
console.log(this.camps); // It is showing data
})
console.log(this.camps); // But it is not working :(
};
this.init();
}])
And in my controller
.controller('AdvanceSettingsController', ['$scope', 'CampaignsService', function ($scope, CampaignsService) {
$scope.CampaignsService = CampaignsService;
}
])
I've read this article to learn promises but it is not working here. I can directly achieve it in controller and it's been working fine. But it consider as a bad coding standard to make controller thick. But when I use service and factory I stuck. My question is why I am not getting ajax data to use in my whole service ? I need to use CampaignsService.camps in my view template as well as in my whole rest script but every time I get undefined. What is happening here? I've asked the same question before but couldn't get any success. Some one please help me to understand about promises and why I am getting this type of error if I'm working same ? This type of question has already been asked before but it was working in controller. May be I am stuck because I'm using it in a service.
A big thanks in advance.
This is not a bug or some tricky functionality. Just like in any other AJAX implementation, you can only access the response data in AngularJS's $http success method. That's because of the asynchronous nature of Asynchronous JavaScript And XML.
And what you have is working.
.controller('AdvanceSettingsController', ['$scope', 'AjaxRequests', function ($scope, AjaxRequests) {
$scope.camps = [];
AjaxRequests.getCampaignsData().then(function(data) {
$scope.camps = data;
});
}
])
And then bind camps:
<div ng-repeat="camp in camps>{{camp.name}}</div>
What's bad in your implementation is that instead of grouping related stuff in services you are writing a big AjaxRequests service for everything. You should have a CampaignsService that has a getData method and inject that in your controller.
Why is this working? Because $http does a $scope.$apply for you, which triggers a digest cycle after the data is loaded (then) and updates the HTML. So before the then callback that ng-repeat is run with [] and after it it's again run but with data from the response because you are setting $scope.camps = data;.
The reason <div ng-repeat="camp in CampaignsService.camps>{{camp.name}}</div> does not work is because of function variable scoping.
The this reference inside of your then callback is not the same as the this reference outside of it.
This will work and uses the common var self = this trick:
var self = this;
this.camps = [];
this.init = function () {
AjaxRequests.getCampaignsData().then(function (response) {
// here "this" is not the one from outside.
// "self" on the other hand is!
self.camps = response.campaigns;
});
};
I have a factory called "Server" which contains my methods for interaction with the server (get/put/post/delete..). I managed to login and get all data successfully when I had all my code in my controller. Now that I want to separate this code and restructure it a little bit I ran into problems. I can still login and I also get data - but data is just printed; I'm not sure how to access the data in controller? I saw some ".then" instead of ".success" used here and there across the web, but I don't know how exactly.
This is my factory: (included in services.js)
app.factory('Server', ['$http', function($http) {
return {
// this works as it should, login works correctly
login: function(email,pass) {
return $http.get('mywebapiurl/server.php?email='+email+'&password='+pass').success(function(data) {
console.log("\nLOGIN RESPONSE: "+JSON.stringify(data));
if(data.Status !== "OK")
// login fail
console.log("Login FAIL...");
else
// success
console.log("Login OK...");
});
},
// intentional blank data parameter below (server configured this way for testing purposes)
getAllData: function() {
return $http.get('mywebapiurl/server.php?data=').success(function(data) {
console.log("\nDATA FROM SERVER: \n"+data); // here correct data in JSON string format are printed
});
},
};
}]);
This is my controller:
app.controller("MainController", ['$scope', 'Server', function($scope, Server){
Server.login(); // this logins correctly
$scope.data = Server.getAllData(); // here I want to get data returned by the server, now I get http object with all the methods etc etc.
…. continues …
How do I get data that was retrieved with $http within a factory to be accessible in controller? I only have one controller.
Thanks for any help, I'm sure there must be an easy way of doing this. Or am I perhaps taking a wrong way working this out?
EDIT: I also need to be able to call factory functions from views with ng-click for instance. Now I can do this like this:
// this is a method in controller
$scope.updateContacts = function(){
$http.get('mywebapiURL/server.php?mycontacts=').success(function(data) {
$scope.contacts = data;
});
};
and make a call in a view with ng-click="updateContacts()". See how $scope.contacts gets new data in the above function. How am I supposed to do this with .then method?(assigning returned data to variable)
My question asked straight-forwardly:
Lets say I need parts of controller code separated from it (so it doesn't get all messy), like some functions that are available throughout all $scope. What is the best way to accomplish this in AngularJS? Maybe it's not services as I thought …
The trick is to use a promise in your service to proxy the results.
The $http service returns a promise that you can resolve using then with a list or success and error to handle those conditions respectively.
This block of code shows handling the result of the call:
var deferred = $q.defer();
$http.get(productsEndpoint).success(function(result) {
deferred.resolve(result);
}).error(function(result) { deferred.reject(result); });
return deferred.promise;
The code uses the Angular $q service to create a promise. When the $http call is resolved then the promise is used to return information to your controller. The controller handles it like this:
app.controller("myController", ["$scope", "myService", function($scope, myService) {
$scope.data = { status: "Not Loaded." };
myService.getData().then(function(data) { $scope.data = data; });
}]);
(Another function can be passed to then if you want to explicitly handle the rejection).
That closes the loop: a service that uses a promise to return the data, and a controller that calls the service and chains the promise for the result. I have a full fiddle online here: http://jsfiddle.net/HhFwL/
You can change the end point, right now it just points to a generic OData end point to fetch some products data.
More on $http: http://docs.angularjs.org/api/ng.%24http
More on $q: http://docs.angularjs.org/api/ng.%24q
$http.get retuns a HttpPromise Object
Server.getAllData().then(function(results){
$scope.data = results;
})
I have a controller like this:
function MyCtrl($scope) {
$scope.doSomething = function(){
alert("Do something!");
}
}
And I have multiple views which depend on this (ie multiple of the below):
<div ng-controller="MyCtrl">
...
</div>
The problem is, the data the controller depends on needs to be loaded in the background (the controller does not load that data), and a callback (dataIsReady()) will be called after the data is ready.
function dataIsReady(){
// TODO: call the doSomething() function
}
Now, I want to basically call the doSomething() function, which is inside MyCtrl, from the dataIsReady() function. How can I do that?
I think what you need is a data service, which you can then inject into your controller. You can call a function on your data service which will handle the retrieval of the data and return a "promise" which can then be used to trigger your callback function when the data has loaded.
Have a look at the following code which is a slightly modified version from egghead.io:
Plunker Demo (w/ local storage): http://plnkr.co/edit/9w2jTg?p=preview
var myApp = angular.module('myApp', []);
myApp.factory('AvengersService', function ($http) {
var AvengersService = {
getAsyncCast: function () {
// $http returns a promise, which has a then function, which also returns a promise
var promise = $http.get("avengers.json") // or some JSON service
.then(function (response) {
// The 'then' function here is an opportunity to modify the response
// The return value gets picked up by the 'then' in the controller.
return response.data;
});
// Return the promise to the controller
return promise;
}
};
return AvengersService;
});
myApp.controller('AvengersCtrl', function($scope, AvengersService) {
// Call the async method and then do something when the data is retrieved
AvengersService.getAsyncCast()
.then(function (asyncData) {
// Callback logic that depends on the data goes in here
console.info("Cast pulled async.");
$scope.avengers.cast = asyncData;
});
});
Hope that helps.
Notice: This approach in this answer is terribly wrong, one should not access to the scope of a controller outside of angular, or outside of controller at all. This would also be terribly slow if you try to call it several times. Other than that, it is fine. I am giving this answer because it is also the simplest way. I would never use that kind of code in production, though. The appropriate way is to write a service to communicate with the controller.
Given that you have defined $scope.doSomething in MyCtrl:
var scp = angular.element('[ng-controller="MyCtrl"]').scope();
scp.doSomething();
Will call doSomething method defined in the controller.