I'm building an app with ionic and I'm showing a loading indicator on every request that loads. When the request finishes, the loading indicator is removed. This works great when a network connection is present.
When offline, the request starts and the loading indicator is show. Problem is that the loading indicator never disappears because the request never finishes. How can I best handle this? I'm thinking about a timeout or something. The best way would be not to start the request at all when a user is offline.
$httpProvider.interceptors.push(function($rootScope) {
return {
request: function(config) {
config.timeout = 5000;
$rootScope.$broadcast('loading:show')
return config
},
response: function(response) {
$rootScope.$broadcast('loading:hide')
return response
}
}
})
add below
responseError: function(response) {
$rootScope.$broadcast('loading:hide')
return response
}
requestError: function(response) {
$rootScope.$broadcast('loading:hide')
return response
}
Related
I have been looking at an application I made a while back and there is a particular page where the details are being loaded last. Because of this, it seems to be queuing the request (there are more than 6 others before it) and that is causing the page to be slow.
I figured I could find a solution to prioritize these requests and I found this:
How to prioritize requests in angular $http service?
So I created my version of it and added it to my interceptors:
// Add our auth interceptor to handle authenticated requests
$httpProvider.interceptors.push('authInterceptor');
$httpProvider.interceptors.push('httpPriorityInterceptor');
The interceptor looks like this:
function factory($injector, $q) {
var requestStack = [], // request stack
$http = null; // http service to be lazy loaded
return {
request: request,
responseError: responseError
};
//////////////////////////////////////////////////
function request(config) {
// Lazy load $http service
if (!$http) {
$http = $injector.get('$http');
}
if (!config.hasBeenRequested) {
config.hasBeenRequested = true;
config.priority = config.priority || 3;
console.log(config);
// add a copy of the configuration
// to prevent it from copying the timeout property
requestStack.push(angular.copy(config));
// sort each configuration by priority
requestStack = requestStack.sort(sort);
// cancel request by adding a resolved promise
config.timeout = $q.when();
}
// return config
return config;
}
function responseError(rejection) {
// check if there are requests to be processed
if (requestStack.length > 0) {
requestStack.reduceRight(function(promise, config) {
return promise.finally(function() {
return $http(config);
});
}, $q.when());
requestStack.length = 0;
}
// return rejected request
return $q.reject(rejection);
}
//////////////////////////////////////////////////
function sort(config1, config2) {
return config1.priority < config2.priority;
}
}
The problem is, it seems to be intercepting template requests too. I have no issue with that, but they are not resolving. Instead I get a lot of errors:
Error: [$templateRequest:tpload] Failed to load template: app/accounts/accounts.html (HTTP status: -1 )
Has anyone encountered this before? Is there something I can do to fix this?
you should know that every request such as html files , css file and ... comes into interceptor.
in your case you dont need to prioritize this files. so you can filter your request like:
if (config.url.toString().toLowerCase().includes("api")) {
//place your functionality
}
I have an angular application making async requests to an API service. Since a lot of the resources are protected on the API Service, I need to intercept the HTTP requests made to the service. But as far as I can see, the interceptor I have defined only intercept page load requests.
Here is an experimental setup I have come up with to illustrate my problem:
myApp = angular.module('myApp', []);
myApp.config(['$httpProvider', function($httpProvider) {
$httpProvider.interceptors.push(function() {
return {
response: function(response) {
console.log(response);
return response;
}
};
});
});
What I am able to see is that, the interceptor intercepts all calls except the API call as you can see from the attached screen shot showing the console output.
The console output, as you can see from the screen shot below, contains the responses logged when the partial templates have been loaded but not when the GET request was made to the API service.
Why does this happen?
Update
I have changed my setup to include all possible combinations of requests and responses now:
$httpProvider.interceptors.push(function() {
return {
request: function(request) {
console.log(request);
return request;
},
requestError: function(request) {
console.log(request);
return config;
},
response: function(response) {
console.log(response);
return response;
},
responseError: function(response) {
console.log(response);
return response;
}
};
});
Now the interceptor intercepts the message but weirdly shows the status of the caught responseError as:
status: -1
although it clearly is a 401.
Update 2
As it turns out, even 401 responses require the CORS header to be added to it. The problem came up since the REST API I was calling used Spring-CORS library which does not include CORS headers on 401 and 403 responses.
It's a cross-site domain issue because although your using localhost your API call domain is different to the UI's (port 8080 & 8081), have a read of this article for more information. You will need add this header in your webserver:
Access-Control-Allow-Origin: http://foo.example
https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS
I am using the following to show a loading screen whenever I am performing a http request however sometimes if there is an error then it will stay loading (because of the backdrop the app becomes unusable). Rather than hide it on every error checker I was wondering if it is possible to call the timeout after 5 seconds?
.config(function($httpProvider) {
$httpProvider.defaults.timeout = 5000;
$httpProvider.interceptors.push(function($rootScope) {
return {
request: function(config) {
$rootScope.$broadcast('loading:show')
return config
},
response: function(response) {
$rootScope.$broadcast('loading:hide')
return response
}
}
})
})
Following Jess's answer it now looks like this :
.config(function($httpProvider) {
$httpProvider.defaults.timeout = 5000;
$httpProvider.interceptors.push(function($rootScope) {
return {
request: function(config) {
$rootScope.$broadcast('loading:show')
return config
},
response: function(response) {
$rootScope.$broadcast('loading:hide')
return response
},
responseError: function(response) {
$rootScope.$broadcast('loading:hide')
return response
},
requestError: function(response) {
$rootScope.$broadcast('loading:hide')
return response
}
}
})
})
However I cannot seem to be able to put an alert in the requestError to inform the user.
Question
How can I implement an alert to notify the user of the error that has occurred?
try adding responseError and requestError so like this:
responseError: function(responseError) {
$rootScope.$broadcast('loading:hide')
return responseError
and do this again with requestError,
This is from the angular http interceptors docs
requestError: interceptor gets called when a previous interceptor threw an error or resolved with a rejection.
responseError: interceptor gets called when a previous interceptor threw an error or resolved with a rejection.
Edit to answer comment:
so if you want to throw a alert on responseError than a add a $rootScope.$broadcast('response:error')
in the responseError function
then in the controller you want to throw the alert in just do a
$scope.$on('response:error', function(){throw the error here});
you can also do the same for requestError
this works because $broadcast -- dispatches the event downwards to all child scopes
I have created http interceptors and attached to my main app as below:
angular.module('app',['ui.router'])
.factory('AuthInterceptor',function($window,$q){
return{
request: function(config){
console.log("config object is");
console.log(config);
if($window.sessionStorage.getItem('token')){
config.headers['x-access-token']= $window.sessionStorage.getItem('token');
}
return config || $q.when(config);
},
response: function(response){
console.log("response object is:");
console.log(response);
if (response['status'] >= 400) {
console.log("Not Authorized.kindly login first");
$state.transitionTo('login');
}
return response || $q.when(response);
}
};
})
.config(function($httpProvider){
$httpProvider.interceptors.push('AuthInterceptor');
});
On the server-side (some express code) I am checking if the user is authorized or not and if not I respond with the following code (only displaying a subset of code to keep things concise):
if(!req.user){
res.send('Not authorized',400);
}
The server code works fine (i can see it in the network tab of the chrome developer tools)
However AuthInterceptor.response() does nto get called.
However do note that the AuthInterceptor.response() does get executed when the response status is 200
So I am confused.. why is it not intercepting 400 statuses ?
If the response status code is outside of the range [200-299], then the responseError interceptor is called.
You need to provide a responseError interceptor:
return {
request: function (config) {...},
responseError: function (rejection) {...}
};
According to http://docs.angularjs.org/api/ng.$http an interceptor has following methods:
request: function(config) {
//we could manipulate query here
return config || $q.when(config);
},
requestError: function(rejection) {
// what is the use case of this?
return $q.reject(rejection);
},
response: function(response) {
// response.status === 200
return response || $q.when(response);
},
responseError: function(rejection) {
// when response failed ...
return $q.reject(rejection);
}
How is requestError triggered and what use-cases can you think of?
One interesting use case is to tear down / undo things that have been set up before a request, and would have been teared down after a response. Examples:
loading indicator
overlay
disabled form fields
Now when the request can't be sent or is rejected by another interceptor, requestError gives you the chance to act appropriately and remove that loading indicator or enable the form fields.