Breeze.JS to use angular.js http - angularjs

I am trying to make Breeze.JS to make use of angular's http service for ajax calls. I followed the the docs (http://www.breezejs.com/documentation/customizing-ajax) and applied it. However it doesn't work.
Further more when I checked breeze source code I saw the following:
fn.executeQuery = function (mappingContext) {
var deferred = Q.defer();
var url = mappingContext.getUrl();
OData.read({
requestUri: url,
headers: { "DataServiceVersion": "2.0" }
},
function (data, response) {
var inlineCount;
if (data.__count) {
// OData can return data.__count as a string
inlineCount = parseInt(data.__count, 10);
}
return deferred.resolve({ results: data.results, inlineCount: inlineCount });
},
function (error) {
return deferred.reject(createError(error, url));
}
);
return deferred.promise;
};
It simply calls OData.read without doing anything about http service. Thus OData makes use of builtin ajax. I don't understand with above code, how it is possible to customize ajax of Breeeze.JS

The problem is that the Breeze OData path does NOT use the Breeze Ajax adapter. Changing the Breeze Ajax Adapter (as the "Breeze Angular Service" does) won't help.
At the moment, both the "OData" and "webApiOData" DataService Adapters delegate to the 3rd party datajs library for AJAX services (and for other OData-related support).
You could replace its odata.defaultHttpClient with a version of your own based on $http. That's not a trivial task. Look here for the source code; it's roughly 160 lines.
I suppose we could write one. It hasn't been a priority.
Until somebody does it or we abandon datajs (not soon if ever), you're stuck with the datajs ajax.
Sorry about that.
p.s. Just about everyone who talks to OData data sources uses the datajs library. Maybe you can talk to the authors of that library and try to get them to support$http.

Quick and dirty hack to simulate $http service
I ran into this issue today. Since the external datajs AJAX methods are used rather than Angular's $http service (as explained by Ward), Breeze queries do not trigger a digest and the models do not get updated.
As with any external-to-angular changes, the simple solution is to wrap any assignments from your queries in a $scope.$apply() function. However, this will quickly clutter up your app so it's a bad idea.
I came up with a quick and dirty hack that so far seems to work well:
I have a dataContextservice which encapsulates all my Breeze queries and exposes methods like getCustomers(), getProducts() etc (inspired by the example on the Breeze site).
When any of these data-access methods completes (ie the promise resolves), I call a triggerAngularDigest() method.
This method simple calls $rootScope.$apply() inside a $timeout().
The $timeout() causes Angular to run the digest on the next tick, i.e. after the data from your Breeze query has been assigned to your models.
All your models update just like when you use $http, no need to call $apply() in your controllers.
Simplified version:
function dataContext($rootScope, $timeout, breeze) {
// config of entity manager etc snipped
return {
getCustomers: function () {
return breeze.EntityQuery.from('Customers')
.using(manager)
.execute()
.then(function(data) {
triggerAngularDigest(); // <-- this is the key
return data;
});
}
};
function triggerAngularDigest() {
$timeout(function() {
$rootScope.$apply();
}, 0);
}
}
myApp.factory('dataContext', dataContext);
Then:
// some controller in your app
dataContext.getCustomers().then(function(data) {
scope.customers = data;
});

Related

GET call failing in AngularJS resource - Strange data result

I have a simple angular resource that I've defined as below:
CompanyService.factory('CompanyService',
function ($resource) {
return $resource('https://baseurl.com/api/values/');
}
);
I then have a controller that calls that resource passing in a success and fail function:
.controller('companyList', function($scope, CompanyService) {
$scope.companies = CompanyService.query(
function(data) {
console.log(data);
return data;
},
function(error){
console.log("Error:");
console.log(error);
}
);
The rest API is a .NET MVC Web API that is extremely basic. I've configured it to return JSON and it simply returns an array of two objects like below. I've also enabled CORS so my angular app, which is hosted in a different domain, can call the api.
[{ID:1, Name:"TEST1"}, {ID:2, Name:"TEST2"}]
I've tested the REST call using jquery and just straight call through browser. All was functional (including the cross site scripting when calling from my angular app just using a straight JavaScript HTTP call).
When I try to call the api from my controller however, it always ends up in the error function. The error object contains a data property that is always populated with the string "resource is required|resource is required|undefined"
When I check the network I see no call to the values end point. It's as if the call is failing before ever being made.
If I change out the url to point to some sample REST api like https://jsonplaceholder.typicode.com/users/ it works fine and I'm able to see the call to "users" in the network traffic, which makes me think there is something wrong with my C# REST endpoint, however all my tests to call the REST endpoint outside of angular work successfully.
Can anyone help? I can't find anyone reporting this issues before anywhere on the net.
should the code be the one below? i didn't test it, just guess.
myModule.factory('CompanyService',
function ($resource) {
return $resource('https://baseurl.com/api/values/');
}
)
.controller('companyList', function($scope, CompanyService) {
CompanyService.query(
function(data) {
$scope.companies = data;
console.log(data);
return data;
},
function(error){
console.log("Error:");
console.log(error);
}
);
I ended up rebuilding my angular app from scratch. My first app was from the angular-seed github and had a handful of libraries already added in for testing and other things. One of those things is was was leading to this error as once I started a new project completely from scratch and added in angular and my REST call things worked perfectly. I've already spent too much time working through this so not going to spend any more time identifying exactly what it is but in case anyone else runs into the problem I did want to answer this one and close the book on it.

AngularJS Unit Testing: Attaching Data from $q.resolve() to object

I'm testing a service that uses another service for API calls, let's call this the data service. The data service is tested elsewhere, so I've abstracted it away with a simple implementation that contains empty functions; I'm returning data via a deferred object and Jasmine's spyOn syntax.
The trouble I'm finding with this approach is when the data is returned, it's not immediately available on the calling object, as it would be if I used $httpBackend. Aware I could just use $httpBackend, but I'd like to know if I've missed something (simple or otherwise) in this approach.
Example section of code I'm trying to test:
storeTheData = dataService.getSomeData();
storeTheData.$promise.then(function(data) {
/*this would work*/
console.log(data);
/*but this would not, when testing using $q*/
_.forEach(storeTheData, function(storedData) {
/*do something with each object returned*/
});
});
As a side note, I don't think the situation is helped by the ...$promise.then on another line, but ideally I wouldn't change the code (I'm providing test coverage to something written a while ago...)
Example of the test:
beforeEach(
...
dataService = {
getSomeData: function () { }
};
getSomeDataDeferred = $q.defer();
spyOn(dataService, "getSomeData").and.returnValue({$promise: getSomeDataDeferred.promise});
...
);
it(...
getSomeDataDeferred.resolve([{obj: "obj1"}, {obj: "obj2"}]);
$scope.$apply();
...
);
With the test described above, the console.log(data) would be testable as the data is accessible from being passed into the .then(). But the data is not immediately available from storeTheData, so storeTheData[0].obj would be undefined. On debug, I can see the data if I go through the promise that was attached to storeTheData via storeTheData.$$state.value
Like I said, I know I could use $httpBackend instead, but is there any way to do this with $q without changing the code under test?
I've not found a way to do this with $q.resolve, but I do have a solution that doesn't involve using the data service or changing the code under test. This is as good, because the main things I wanted to avoid were testing the data service as a side effect and changing the code.
My solution was to create a $resource object via $injector...
$resource = $inject.get("$resource");
...then return that in my basic implementation of the data service. This means I could use $httpBackend to respond to the request to an end point that isn't reliant on the data service's definition staying consistent.
dataService = {
getSomeData: function () {
/* new code starts here */
var resource = $resource(null, null, {
get: {
method: "GET",
isArray: true,
url: "/getSomeData"
}
});
return resource.get();
/* new code ends here */
}
};
...
$httpBackend.when("GET", "/getSomeData").respond(...;

how to make library of primary functions in AngularJS

I want to develop set of functions(sort of library) for CRUD in AngularJS so I can reuse them for couple of entities of my project. For server communication I made factory of $resource and using accordingly. $resource factory looks like this:
Model File:
var get_entity_model = angular.module("app.getentity", []).factory('getEntity', ['$resource', function($resource) {
return{
entity_view: $resource(baseurl+'/rest/'+serviceName+'/entity/:id/?app_name='+appName+'&fields=*', null, {'update': { method:'PUT' }})
}
}]);
And here how I'm using it in controller
Controller File:
getEntity.entity_view.get(
function(entity_list){
},
function(error){
}
)
Here entity_view is the table name. I'm passing all related functions like pagination and sub request to get the data of related tables etc code I put into success function of above request.
Now I want to make a library where I can define all this stuff and simply by calling the function I should be able to get all this stuff like:
entity.getEntity()
Should return same result as above code.
I tried with creating factory for above task but seems it need callback function and function at factory will return only data which I'm already getting from my model file so I need to make it compact and easy to use.
Factory Code at factory file:
var api = angular.module("app.entity_api", []).factory('entity_factory', ['$resource','getEntity',function($resource,getEntity) {
var entity_factory = {};
entity_factory.get_entity = function(callback){
getEntity.entity_view.get().$promise.then(
function(data){
callback(data.record);
}
);
}
return entity_factory;
}]);
And here how I call the function in controller:
Controller code:
api.controller("sample",['entity_factory','getEntity','$scope',function(entity_factory,getEntity,$scope){
$scope.init = function(){
entity_factory.get_entity(
function(data){
console.log(data);
}
);
}
$scope.init();
}])
Problem is that my entity_factory code will return only the data from server rest of the additional code I've to do in callback function which seems not much difference than my current exercise. So, the question is how can I achieve my goal to make a library of functions with additional code which return complete compiled result to make the code reusable for other entities and compact.
I like that you're a thinking of making a library but in this case, don't reinvent the wheel and save your precious time. Check out Restangular and your task will be a lot easier. Restangular is an AngularJS service that simplifies common GET, POST, DELETE, and UPDATE requests with a minimum of client code. It's a perfect fit for any WebApp that consumes data from a RESTful API.

AngularJS Execute function after a Service request ends

I am using AngularJS Services in my application to retrieve data from the backend, and I would like to make a loading mask, so the loading mask will start just before sending the request. but how can I know when the request ends?
For example I defined my servive as:
angular.module('myServices', ['ngResource'])
.factory('Clients', function ($resource) {
return $resource('getclients');
})
.factory('ClientsDetails', function ($resource) {
return $resource('getclient/:cltId');
})
So I use them in my controller as:
$scope.list = Clients.query();
and
$scope.datails = ClientsDetails.get({
date:$scope.selectedId
});
So the question would be, how to know when the query and get requests ends?
Edit:
As a side note in this question I've been using using angularjs 1.0.7
In AngularJS 1.2 automatic unwrapping of promises is no longer supported unless you turn on a special feature for it (and no telling for how long that will be available).
So that means if you write a line like this:
$scope.someVariable = $http.get("some url");
When you try to use someVariable in your view code (for example, "{{ someVariable }}") it won't work anymore. Instead attach functions to the promise you get back from the get() function like dawuut showed and perform your scope assignment within the success function:
$http.get("some url").then(function successFunction(result) {
$scope.someVariable = result;
console.log(result);
});
I know you probably have your $http.get() wrapped inside of a service or factory of some sort, but you've probably been passing the promise you got from using $http out of the functions on that wrapper so this applies just the same there.
My old blog post on AngularJS promises is fairly popular, it's just not yet updated with the info that you can't do direct assignment of promises to $scope anymore and expect it to work well for you: http://johnmunsch.com/2013/07/17/angularjs-services-and-promises/
You can use promises to manage it, something like :
Clients.query().then(function (res) {
// Content loaded
console.log(res);
}, function (err) {
// Error
console.log(err);
});
Another way (much robust and 'best practice') is to make Angular intercepting your requests automatically by using interceptor (see doc here : http://docs.angularjs.org/api/ng.$http).
This can help too : Showing Spinner GIF during $http request in angular
As left in a comment by Pointy I solved my problem giving a second parameter to the get function as following:
$scope.datails = ClientsDetails.get({
date:$scope.selectedId
}, function(){
// do my stuff here
});

angularJS unit testing where run contains a HTTP request?

I am fairly new to AngularJS and am trying to learn some best practices. I have things working, but would like to start adding some unit tests to my modules and controllers. The first one I am looking to tackle is my AuthModule.
I have an AuthModule. This Module registers a Factory called "AuthModule" and exposes things like "setAuthenticatedUser" and also fields like "isLoggedIn" and "currentUser". I think this is a fairly common pattern in an AngularJS application, with some variations on the specific implementation details.
authModule.factory(
'AuthModule',
function(APIService, $rootScope) {
var _currentUser = null;
var _isLoggedIn = false;
return {
'setAuthenticatedUser' : function(currentUser) {
_currentUser = currentUser;
_isLoggedIn = currentUser == null ? false : true;
$rootScope.$broadcast('event:authenticatedUserChanged',
_currentUser);
if (_isLoggedIn == false) {
$rootScope.$broadcast('event:loginRequired')
}
$rootScope.authenticatedUser = _currentUser;
$rootScope.isLoggedIn = _isLoggedIn;
},
'isLoggedIn' : _isLoggedIn,
'currentUser' : _currentUser
}
});
The module does some other things like register a handler for the event "loginRequired" to send the person back to the home screen. These events are raised by the AuthModule factory.
authModule.run(function($rootScope, $log, $location) {
$rootScope.$on("event:loginRequired", function(event, data) {
$log.info("sending him home. Login is required");
$location.path("/");
});
});
Finally, the module has a run block which will use an API service I have to determine the current logged in user form the backend.
authModule.run(
function(APIService, $log, AuthModule) {
APIService.keepAlive().then(function(currentUser) {
AuthModule.setAuthenticatedUser(currentUser.user);
}, function(response) {
AuthModule.setAuthenticatedUser(null);
});
});
Here are some of my questions:
My question is how would you setup tests for this? I would think that I would need to Mock out the APIService? I'm having a hard time because I keep getting unexpected POST request to my /keepalive function (called within APIService.keepAlive())?
Is there any way to use $httpBackend in order to return the right response to the actual KeepAlive call? This would prevent me from having to mock-out the API service?
Should I pull the .run() block out which obtains the current logged in user out of the AuthModule and put it into the main application? It seems no matter where I put the run() block, I can't seem to initialize the $httpbackend before I load the module?
Should the AuthModule even be its own module at all? or should I just use the main application module and register the factory there?
Run blocks are the closest thing in Angular to the main method. A run block is the code which needs to run to kickstart the application. It is executed after all of the service have been configured and the injector has been created. Run blocks typically contain code which is hard to unit-test, and for this reason should be declared in isolated modules, so that they can be ignored in the unit-tests.angularjs docs
I suggest you take a look at this authentication service, using a service is the way to go.
Hopefully this would help ... Good luck

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