I have this in my Angular service:
return $resource(BASE + '/cases/:id',
{id: '#id'}, {
status: {method: 'GET', params: {status: '#status'}}
});
When using the method added to the $resource definition along with the promise's .then() function, I'm getting an error:
Cases.status({status: 'pending'})
.then(function(res) {
console.log(res);
$scope.cases.pending = res.data.cases;
})
.then(function() {
$scope.tabbed.pending = true;
});
After the above snippet is run, the error I get is:
TypeError: undefined is not a function on this line: .then(function(res) {
Can I not use these functions as I usually do when I'm using an extra method defined on the $resource?
I think you need to use $promise of $resource object which will call success function when actual promise gets resolved & then you could proceed with the promise chain.
CODE
Cases.status({status: 'pending'})
.$promise
.then(function(res) {
console.log(res);
$scope.cases.pending = res.data.cases;
})
.then(function(cases) {
$scope.tabbed.pending = true;
});
You have to use $promise in order to access the promise is created on that call, like this:
Cases.get({id: 123}).$promise
.then(function (success) {
//do something
}).then(function (error) {
//do something else
})
Or you can send both functions as callbacks:
Cases.get({id: 123}, function (success) {
//do something
}, function (error) {
//do something else
});
Tip
You don't have to add a new method to that $resource to send a GET to the same url, you can just have your $resource be plain:
//... code
return $resource(BASE + '/cases'});
and when you pass the parameters to it (if you are passing them as in the example) it will match the keys according to the object so you can just say:
Cases.get({status: 'something'}).$promise
.then(function(success){
//... code
})
.then(function(err){
//... code
});
Cases.get({id: 123}).$promise
.then(function(success){
//... code
})
.then(function(err){
//... code
});
Related
I've been working on a project for a while on my current job and they're using Angulajs for the front-end. Recently I'm trying to implement the ES6 standard. The project uses a Factory to wrap the API services from the backend like this:
'use strict';
angular.module('products').factory('Products', ['$resource',
($resource)=> {
return $resource('api/products/:productId', {
productId: '#id'
},{
update: {
method: 'PUT'
},
getProductsByType : {
url: 'api/:schoolIdProduct/products/:Type',
params: {
schoolIdProduct: ':schoolIdProduct',
Type: ':Type'
},
isArray: true
}
});
}
]);
So now right now when we call the Factory from the controller I just add the factory and then call the function like this:
$rootScope.supplies = Products.getProducts({
schoolIdProduct: schoolId,
Type: 'Supplies'
});
So when I try to use the arrow function and then() to wait for the response the browser console tells me that is not a function. How do I change my code to use the ES6 standard and get something like this?
Products.getProducts({
schoolIdProduct: schoolId,
Type: 'Supplies'
}).then( (response) =>{
$rootScope.supplies = response;
});
So the thing you are not getting the promise from the response so need to promisify your response either with $q or bluebird.
both solutions are mentioned and you are using ngResource for getting resonses.
angular doc link using $q: https://docs.angularjs.org/api/ng/service/$q
you may also use bluebird library and convert responses using promise library
let promise = new Promise(function (resolve, reject) {
try {
resolve(Products.getProducts({
schoolIdProduct: schoolId,
Type: 'Supplies'
}))
} catch (error) {
reject( error)
}
})
return promise
I have a problem with angular-ui typeahead component. It does not show values populated by angular resources, however using $http works well. I suppose I missing some trick here with asycn call and correct population of returned values.
Working code
$scope.searchForContact = function(val) {
return $http.get('/api/contacts/search', {
params: {
q: val
}
}).then(function(response){
return response.data.map(function(item){
return item.name;
});
});
};
Not working code
$scope.searchForContact = function(val) {
return Contact.search({q: val}, function(response){
return response.map(function(item){
return item.name;
});
});
});
...
'use strict';
app.factory("Contact", function($resource, $http) {
var resource = $resource("/api/contacts/:id", { id: "#_id" },
{
'create': { method: 'POST' },
'index': { method: 'GET', isArray: true },
'search': { method: 'GET', isArray: true, url: '/api/contacts/search', params: true },
'show': { method: 'GET', isArray: false },
'update': { method: 'PUT' },
'destroy': { method: 'DELETE' }
}
);
return resource;
});
Pug template code
input.form-control(
type='text'
ng-model='asyncSelected'
uib-typeahead='contact for contact in searchForContact($viewValue)'
typeahead-loading='loadingLocations'
typeahead-no-results='noResults'
)
i.glyphicon.glyphicon-refresh(ng-show='loadingLocations')
div(ng-show='noResults')
i.glyphicon.glyphicon-remove
|
|No Results Found
Angular resources are working fine, including search endpoint - I just output on page result returned by the search endpoint. In both results should be just an array with string values. What am I doing wrong?
The difference between $http.get and your Contact.search is that the first one returns a promise and the latter doesn't. Any $resource method will usually be resolved to the actual response. I'll show that with an example.
Getting data with $http
var httpResult = $http.get('http://some.url/someResource').then(function(response) {
return response.map(function(item) { return item.name });
});
The httpResult object contains a promise, so we need to use then method to get the actual data. Moreover, the promise will be resolved to the mapped array, which is the expected result.
Getting data with $resource
var someResource = $resource('http://some.url/someResource');
var resourceResult = someResource.query(function(response) {
return response.map(function(item) { return item.name });
});
The resourceResult isn't a promise here. It's a $resource object which will contain the actual data after the response comes from the server (in short, resourceResult will be the array of contacts - the original, not mapped, even though there is a map function). However, the $resource object contains a $promise property which is a promise similar to one returned by $http.get. It might be useful in this case.
Solution
I read in documentation that in order to make uib-typehead work properly, the $scope.searchForContact needs to return a promise. Instead of passing the callback function to search, I would simply chain it with the $promise from $resource object to make it work.
$scope.searchForContact = function(val) {
return Contact.search({q: val}).$promise.then(function(response){
return response.map(function(item){
return item.name;
});
});
});
Let me know if it works for you.
I'm trying to pass a params object to the $http.get() service. My params look like this:
var params = {
one: value,
two: value
}
And I'm trying to pass them into my function like so:
$http.get('/someUrl', params)
.success(function(data) {
// stuff
})
.error(function(data) {
// error stuff
});
Is this the correct way to go about doing this?
The second argument of $http is a config object (see documentation). Amongst other properties, the config object accepts a params property:
params – {Object.<string|Object>} – Map of strings or objects which will be serialized with the paramSerializer and appended as GET parameters.
Therefore you have to pass the parameters as such
var config = {
params: {
one: value,
two: value
}
}
$http.get('/someUrl', config).then(...)
Suppose the values for the parameters are respectively '1' and '2', $http will send a GET request to the following url:
/someUrl?one=1&two=2
As a side note, try to avoid using success and error functions on $http. They have been deprecated as of angular 1.4.4. Use the methods then with a success and an error callback instead, or then with only a success callback and catch.
Service/Factory
For the actual call use a factory or service that you can inject to the controllers you need it in. This is an example factory passing parameters
.factory('Chats', function ($http, $rootScope, $stateParams) {
return {
all: function () {
return $http.get('http://ip_address_or_url:3000/chats', { params: { user_id: $rootScope.session } })
}
};
});
Controller
In your controller you use the service like this
.controller('ChatsCtrl', function ($scope, Chats) {
Chats.all().success(function (response) {
$scope.chats = response;
})
})
I have faced similar issue in recent time and I had to add few additional details to request (I used accepted answer with some headers):
$http.get(url, {
params: {
paramOne: valueOne,
paramTwo: valueTwo,
...
},
headers: {
'key': 'value'
},
// responseType was required in my case as I was basically
// retrieving PDf document using this REST endpoint
// This is not required in your case,
// keeping it for somebody else's reference
responseType: 'arraybuffer'
}).success(
function(data, status, headers, config) {
// do some stuff here with data
}).error(function(data) {
// do some stuff here with data
});
The $http documentation suggest that the second argument to the $http.get method is an object which you can pass with it "param" object.
Try something like this:
$http.get('/someUrl', {params: params})
.success(function(data) {
// stuff
})
.error(function(data) {
// error stuff
});
I have functions like the getData function below.
I understand that $http returns a promise. In my current set up I am using $q so that I can do some processing of the results and then return another promise:
var getData = function (controller) {
var defer = $q.defer();
$http.get('/api/' + controller + '/GetData')
.success(function (data) {
var dataPlus = [{ id: 0, name: '*' }].concat(data);
defer.resolve({
data: data,
dataPlus: dataPlus
});
})
.error(function (error) {
defer.reject({
data: error
});
});
return defer.promise;
}
Is there any way that I can do this without needing to use the AngularJS $q (or any other $q implementation) or is the code above the only way to do this? Note that I am not looking for a solution where I pass in an onSuccess and an onError to the getData as parameters.
Thanks
As you say $http.get already returns a promise. One of the best things about promises is that they compose nicely. Adding more success, then, or done simply runs them sequentially.
var getData = function (controller) {
return $http.get('/api/' + controller + '/GetData')
.success(function (data) {
var dataPlus = [{ id: 0, name: '*' }].concat(data);
return {
data: data,
dataPlus: dataPlus
};
})
.error(function (error) {
return {
data: error
};
});
}
This means that using getData(controller).then(function (obj) { console.log(obj) });, will print the object returned by your success handler.
If you want you can keep composing it, adding more functionality. Lets say you want to always log results and errors.
var loggingGetData = getData(controller).then(function (obj) {
console.log(obj);
return obj;
}, function (err) {
console.log(err);
return err;
});
You can then use your logging getData like so:
loggingGetData(controller).then(function (obj) {
var data = obj.data;
var dataPlus = obj.dataPlus;
// do stuff with the results from the http request
});
If the $http request resolves, the result will first go through your initial success handler, and then through the logging one, finally ending up in the final function here.
If it does not resolve, it will go through the initial error handler to the error handler defined by loggingGetData and print to console. You could keep adding promises this way and build really advanced stuff.
You can try:
Using an interceptor which provides the response method. However I don't like it, as it moves the code handling the response to another place, making it harder to understand and debug the code.
Using $q would be the best in that case IMO.
Another (better ?) option is locally augmented transformResponse transformer for the $http.get() call, and just return the $http promise.
I'm still new to Angular and promises so I hope I have the correct idea here.
I currently have a data layer service which uses restangular to get some data, then returns a promise, like this...
dataStore.getUsers = function (params) {
return users.getList(params);
};
Then, my controller which has called this function receives a promise back, like this...
$dataStore.getUsers(params).then(function (response) {
$scope.users = response;
}, function(response) {
$log.error("Get users returned an error: ", response);
});
This is working well, but I'd like to use the promise inside of my datastore before passing it back. I'd like to use the .then() method to check if it failed and do some logging, then, from the sucess function and from the failure function I'd like to return the original promise back to my controller.
My controller would then be able to use the .then() method like it already is, in fact, I don't want my controller code to change at all, just my datastore code.
Here's some semi-pseudo code to show what I'd like my datastore function to do...
dataStore.getUsers = function (params) {
users.getList(params).then(function (response) {
$log("server responded")
return original promise;
}, function(response) {
$log.error("server did not respond");
return original promise;
});
};
You were actually not far off at all in your pseudo code. Promises chain:
dataStore.getUsers = function (params) {
return users.getList(params).then(function (response) {
$log("server responded")
return response;
}, function(failure) {
$log.error("server did not respond");
// change to throw if you want Angular lever logs
return $q.reject(failure);
});
};
The controller now gets resolved/rejected with the same value. The log requires tapping into the promise so you must add a .then handler to deal with it. Other promise libraries have convinicene methods for this but $q is minimalistic in this regard.
Alternatively, you can use nicer catch syntax, as well as propagate the errors to your logs:
dataStore.getUsers = function (params) {
return users.getList(params).then(function (response) {
$log("server responded")
return response;
}).catch(function(failure) {
$log.error("server did not respond");
throw failure;
});
};