How to trigger an error during Backbone model fetch call? - backbone.js

What is the right way to trigger error callback in Backbone's fetch process?
For example, I have code as follows:
this.model.fetch({
success: function(model, response, options){
console.log('data loaded');
},
error: function(model, response, options){
console.log('error loading data');
}
});
In the model I have a parse function akin to this:
parse: function(response, options){
var data = response.modeldata);
if(data.inaccessible == true) {
//trigger error
} else return data;
},
What do I need to put inside the conditional block to trigger the error callback?

If you want to execute the callback attached to the error option, you'll need to modify your model's parse function as follows.
parse: function(response, options) {
var data = response.modeldata;
var error = options.error;
if (data.inaccessible === true) {
if ( error ) error( this, response, options );
} else {
return data;
}
}
Hope this helps.

Related

Using $promise.then() after Interceptor erroneously calls successCallback

i want to use $promise.then(successCallback,errorCallback) after the interceptor did the basic message handling. Somehow it always runs into the successCallback and never into the errorCallback if i get error 400,401 etc. If i remove the interceptor it works fine. I also found out that i could create a new promise in the interceptors to solve this problem but i think this is not the best way to go. In my case i only want an interceptor for some basic message handling and then continue in the main controller with the main logic. This is currently not possible because i always run into the successCallback if i get an error.
Did i understand something wrong?
Here an example what i want:
var resourceObj = $resource("url/abc/:action/:id", {}, {
getMember: {
method: 'GET',
params: { action: 'member' },
interceptor: {
responseError: function(response) {
console.log("Interceptor responseError");
//Show some default error messages here
return response; //create new promise with $http(response); to solve the problem?
},
response: function(response) {
console.log("Interceptor responseSuccess");
//Show some default success messages here
return response; //create new promise with $http(response); to solve the problem?
}
}
}
});
myModule.controller('myCtrl', function($scope) {
$scope.checkMember() = function(memberId) {
resourceObj.getMember({ id: memberId }, {}).$promise.then(
function(responseOK) { //successCallback
console.log(responseOK);
$scope.testMember = responseOK.data; // or if no interceptor is used responseOK.toJSON()
//do some stuff here after async call is finished
},
function(responseError) { //errorCallback, never called in error case if an interceptor is used.
console.log(responseError);
//do maybe some advanced error handling here after async call is finished
}
);
}
});
It is important to re-throw the error response.
var resourceObj = $resource("url/abc/:action/:id", {}, {
getMember: {
method: 'GET',
params: { action: 'member' },
interceptor: {
responseError: function(response) {
console.log("Interceptor responseError");
//Show some default error messages here
̶r̶e̶t̶u̶r̶n̶ ̶r̶e̶s̶p̶o̶n̶s̶e̶;̶
//IMPORTANT re-throw error response
throw response;
},
response: function(response) {
console.log("Interceptor responseSuccess");
//Show some default success messages here
return response;
}
}
}
});
If the error response is simply returned, it will be erroneously converted from a rejection to a success.

how to throw an error in a $http promise

I have an angular service that wraps my rest api calls and returns a $http promise.
My question is how do I throw an error so that a promise that triggers the .error method gets called? I don't want to just throw error since I want it to use the .success/.error in the calling function rather than doing a try catch block around it.
myFunction: function(foo)
if (foo) {
return $http.put(rootUrl + '/bar', {foo: foo});
}
else {
//what do I return here to trigger the .error promise in the calling function
}
You don't need $q.defer(). And else too. You can use reject directly:
myFunction: function(foo) {
if (foo) {
return $http.put(rootUrl + '/bar', {foo: foo});
}
return $q.reject("reject reason");
}
See https://docs.angularjs.org/api/ng/service/$q#reject
You'll want to create your own promise using $q. Here's how I did something similar in a recent project:
app.service('allData', ['$http','$q',function($http,$q) {
return {
getJson: function() {
return $q(function(resolve, reject) { // return a promise
$http.get('/path/to/data.json', {cache:true})
.success(function(data) {
if (angular.isArray(data)) { // should be an ordered array
// or any other test you like that proves it's valid
resolve(data);
} else {
reject("Invalid JSON returned");
console.log(data);
};
})
.error(function(data) {
reject("Invalid data returned");
console.log(data);
});
});
}
};
}]);
And in my controller:
allData.getJson().then(function(json) {
// success, do something with the json
}, function(reason) { // failure, .getJson() had some kind of error
alert('Sorry, unable to retrieve data from the server.')
console.error(reason);
});
First inject the $q-service in your service. Then in your else:
else {
var deferred = $q.defer();
deferred.reject("reject reason, foo was false");
return deferred.promise;
}
Not as clever as Blazemonger's, but its quick to do.
You can raise or throw a custom error using throw new Error ("custom error").
For http:
http.get('url').toPromise().then (result =>{
throw new Error ("My Custom Error") // New Custom error New is optional w
}).catch(err => {
throw err
}); // catch will catch any error occur while http call

How do I test an $httpBackend POST error state with AngularJS / Karma?

I'm trying to write a unit test for my Angular Service and here's a function in the service:
login = function(authObject) {
deferred = $q.defer();
$http({
url: '/api/v1/session/create',
method: 'POST',
data: authObject
}).success(function(response) {
var user;
if (response.status === 'ok' && response.user && response.authenticated === true) {
user = response.user;
}
return deferred.resolve(response);
}).error(function(data) {
deferred.reject(data);
return $state.go('api_error');
});
return deferred.promise;
};
I can successfully test the success case with something like:
it('should go to the api error state', function() {
var authObject;
authObject = {
username: 'a#b.com',
password: 'c'
};
$httpBackend.expectPOST('/api/v1/session/create').respond(someData);
userService.login(authObject).then(function(response) {
return console.log("not error", response);
}, function(response) {
return console.log("error", response);
});
return expect($state.go).toHaveBeenCalledWith('api_error');
});
That works fine, however if I do:
$httpBackend.expectPOST('/api/v1/session/create').respond(500, 'error');, then the error case doesn't get called. What am I doing wrong?
In order for your .then() error callback to be called, the previous promise in the chain should result in error (e.g. throw an Exception) or be rejected.
Returning 500 will cause the error callback in your login() method to be called, but since that callback neither throws an Error nor gets rejected, your chained error callback won't be called.
E.g. changing:
}).error(function(data) {
deferred.reject(data);
return $state.go('api_error');
});
to:
}).error(function(data) {
return deferred.reject(data);
//return $state.go('api_error');
});
would work (but it doesn't do what you want :D).
I am not familiar with ui-router, but in this case it could be possible that $state.go() aborts the current execution chain, so I am not sure the following would work:
}).error(function(data) {
$state.go('api_error');
return deferred.reject(data);
});

How do I get the HTTP response status code in AngularJS 1.2

Using ngResource in AngularJS 1.2rc(x), how do I get the status code now?
RestAPI.save({resource}, {data}, function( response, responseHeaders ) {
});
where RestAPI is my ngResource.
The response has the $promise object and the resource returned from the server but not a status anymore. The responseHeaders() function only has a status if the server injects the status code into the header object, but not the true returned status code. So some servers may serve it and some might not.
You can use the promiss callbacks then, catch and finally after the $resource call.
For example. If you want to catch an error after a call, you would do something like this:
RestAPI.save({resource}, {data}, callbackFunction).$promise.catch(function(response) {
//this will be fired upon error
if(response.status == 500) alert('Something baaad happend');
}).then(function() {
//this will be fired upon success
});
The response object will have status and the statusText properties. status being an integer status code and statusText the text. You'll also have the data property containing the server response.
edit: as suggested, it was response.status
You must add an interceptor inside your resource declaration. Like this:
var resource = $resource(url, {}, {
get: {
method: 'GET'
interceptor: {
response: function(response) {
var result = response.resource;
result.$status = response.status;
return result;
}
}
}
});
Usage:
resource.get(params, function(result) {
console.log(result.$status)
});
IMO status code should have been provided by default.
There is an issue for this https://github.com/angular/angular.js/issues/8341
For anyone using a newer version of Angular, looks like we've had access to the status code as a 3rd param to the transformResponse function since angular 1.3, but it was never documented properly in the $resource docs.
I agreed responseHeaders() function will only return response's header,but you can custom it and it's useful anyway.
1.
To solve you problem. With the following:($$service is my $resource instance.)
var serve = new $$service();
serve.id = "hello_wrongPath"; // wrong path,will return 404
serve.$get()
.then(function (data) {
console.log("~~~hi~~~");
console.log(data);
return data;
})
.catch(function (error) {
console.log("~~~error~~~");
console.log(error);
console.log(error.status); // --> 404
console.log(error.statusText); // --> "Not Found"
console.log(error.config.timeout); // --> 5000
console.log(error.config.method); // --> GET
console.log(error.config.url); // --> request url
console.log(error.headers("content-type"));// --> "text/plain"
return error.$promise;
})
.finally(function(data){
console.log("~~~finally~~~");
console.log(data); // --> undefined
});
In this way,u can only catch status,statusText,timeout,method,headers(same with responseHeaders) in ERROR response.
2.
If you want to see response details in success response,I used a interceptor like this:
ng.module("baseInterceptor", [])
.factory("baseInterceptor", ["$q", function ($q) {
return {
'request': function (config) {
console.info(config);
//set timeout for all request
config.timeout = 5000;
return config;
},
'requestError': function (rejection) {
console.info(rejection);
return $q.reject(rejection);
},
'response': function (response) {
console.log("~~interceptor response success~~");
console.log(response);
console.log(response.status);
console.log(response.config.url);
return response;
},
'responseError': function (rejection) {
console.log("~~interceptor response error~~");
console.log(rejection);
console.log(rejection.status);
return $q.reject(rejection);
}
};
}]);
and then add interceptor to module:
.config(["$httpProvider", function ($httpProvider) {
$httpProvider.interceptors.push("baseInterceptor");
}])
You can get response status like this:
$http.get(url).then(function(response){
console.log(response.status); //successful status like OK
}, function(response){
console.log(response.status); //error status like 400-Bad Request
})
I'm using AngularJS v1.5.6, and I do it like this (in my case I put the "getData" method inside a service):
function getData(url) {
return $q(function (resolve, reject) {
$http.get(url).then(success, error);
function success(response) {
resolve(response);
}
function error(err) {
reject(err);
}
});
}
then in the controller (for example), call that like this:
function sendGetRequest() {
var promise = service.getData("someUrlGetService");
promise.then(function(response) {
//do something with the response data
console.log(response.data);
}, function(response) {
//do something with the error
console.log('Error status: ' + response.status);
});
}
As documentation says, the response object has these properties:
data – {string|Object} – The response body transformed with the transform functions.
status – {number} – HTTP status code of the response.
headers – {function([headerName])} – Header getter function.
config – {Object} – The configuration object that was used to generate the request.
statusText – {string} – HTTP status text of the response.
See https://docs.angularjs.org/api/ng/service/$http
Hope it helps!
I think the right answer is a combination of Bardiel's and Ara's answers.
After adding an interceptor inside your resource declaration. Like this:
var resource = $resource(url, {}, {
get: {
method: 'GET'
interceptor: {
response: function(response) {
var result = response.resource;
result.$status = response.status;
return result;
}
}
}
});
Use it as below:
RestAPI.save()
.query(function(response) {
// This will return status code from API like 200, 201 etc
console.log(response.$status);
})
.$promise.catch(function(response) {
// This will return status code from server side like 404, 500 etc
console.log(response.status);
});
I had faced the similar problem.I looked into the angular lib and added a few lines to have status returned in the response itself.In this file,find where promise is being returned.
Replace code block starting with
var promise = $http(httpConfig).then(function(response)
with the following
var promise = $http(httpConfig).then(function(response) {
var data = response.data,
promise = value.$promise;
if (data) {
// Need to convert action.isArray to boolean in case it is undefined
// jshint -W018
if ( angular.isArray(data) !== (!!action.isArray) ) {
throw $resourceMinErr('badcfg', 'Error in resource configuration. Expected ' +
'response to contain an {0} but got an {1}',
action.isArray?'array':'object', angular.isArray(data)?'array':'object');
}
// jshint +W018
if (action.isArray) {
value.length = 0;
forEach(data, function(item) {
value.push(new Resource(item));
});
} else {
copy(data, value);
value.$promise = promise;
}
}
value.status = response.status;
value.$resolved = true;
response.resource = value;
return response;
}, function(response) {
value.status = response.status;
value.$resolved = true;
(error||noop)(response);
return $q.reject(response);
});
or you can add this line
value.status = response.status;
and then access status in code like reponse.status.Though,this is kind of hack but worked for me.I also had to make changes in the minified version.

Backbone fetch hitting the wrong url

I'm have the following backbone model
define(["jquery", "underscore", "backbone"],
function ($, _, Backbone) {
var file_upload = Backbone.Model.extend({
url: 'http://localhost:8080/rest/customForms'
});
return file_upload;
}
I have a view loaded at
localhost:38559/app/forms.html
which tries to do a post with the following code
var fd = document.getElementById('fileToUpload').files[0];
var file = new file_upload();
file.fetch({data: $.param({fileToUpload: fd}),
type: 'POST',
success: function(d){
console.log('success');
}
});
but this seems to just do a get request to forms.html passing fd as a param. I've also tried overriding the sync method in file_upload
sync: function (method, model, options) {
var self = this;
options = _(options).clone();
var error = options.error;
options.error = function (jqXHR, textStatus, errorThrown) {
alert('error');
if (error)
error(jqXHR, textStatus, errorThrown);
};
var success = options.success;
options.success = function (data, textStatus, jqXHR) {
if (success && data) {
alert("Success uploading form.");
success(data, textStatus, jqXHR);
}
else
alert("Error uploading form. Please try entering again.");
};
var params = {
type: 'POST'
};
$.ajax(_.extend(params, options));
}
}
I'm doing posts in other parts of the app with similar code so can't figure out why with this code the fetch does a get request to the page it's called on rather than a post to the url specified in the model. Does anyone have any ideas?
Thanks,
Derm
Ugh - finally found the issue coming back to this. The file upload was been done on a button click event. I needed to call preventdefault to force the use of the models url rather than the pages url. Annoying issue - dunno how I missed it! Code now is
uploadForm: function (e) {
e.preventDefault();
var self = this;
var fd = document.getElementById('fileToUpload').files[0];
var file = new file_upload();
file.fetch({data: $.param({fileToUpload: fd}),
type: 'POST',
success: function(d){
console.log('success');
}
});
},

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