I have a reverse proxy that checks global authentication for several applications. When the user is disconnected but still trying to use my application, the proxy sends a 302 response :
HTTP/1.1 302 Found
Date: Wed, 11 Sep 2013 09:05:34 GMT
Cache-Control: no-store
Location: https://other.url.com/globalLoginPage.html
Content-Length: 561
Content-Type: text/html; charset=iso-8859-1
Via: 1.1 my-proxy.com
Connection: Keep-Alive
In angularJs, the error callback is called but the response headers are empty, status is 0 and data is an empty string. So it seems that I really can't do nothing to handle the response...
I've seen several questions on the subject, and I still don't understand what is going on (CORS because of the proxy or different domain in the location?, 302 browser behavior?).
In particular there is this part from an answer (https://stackoverflow.com/a/17903447/1093925):
Note: If your server sets a response code of 301 or 302, you will not be able to get the Location header, as it will be automatically and transparently followed by the XMLHttpRequest object.
What about this XMLHttpRequest object?
In a very old version of Chrome (can't use a newer version) I can see that a corresponding request in the network panel, but it seems to fail as there is no response.
In the latest version of firefox, there is nothing going on.
Can I do anything about that, since I can't change the proxy configuration and response?
Update:
I replayed my scenario today, and thanks to a newer version of firebug, I was able to get more details about what is going on.
I was not far from the anwser in my question : Cross domain policy.
Since it is an HTTP request made by my application, the browser denies the following XMLHttpRequest (which in-app looks like the same request). Hence the error and the empty response.
So I think there is nothing special I can do about it
I had the same problem in my app. You can't really "catch" a 302 redirect response. The browser catches it before Angular get it's hand on it. so actually, when you do receive your response - it is already too late.
The bad news: it's not a problem in the angular platform. The xmlHttpRequest do not support this kind of behaviour, and the browser act before you can do anything about it. reference: Prevent redirection of Xmlhttprequest
The good news: there are many ways to bypass this problem, by intercepting the response- and find some way to recognize that it's your lovable 302. This is a hack, but it's the best you can do at the moment.
So. For example, in my app, the redirect was back to the login.html page of the app, and in the app i got the response with a 200 status and the data of the response was the content of my login.html page. so in my interceptor, i checked if the result is a string (usually not! so- no efficiency prob..) and if so- checked if it's my login.html page. that way, i could catch the redirect and handle it my way.
yourApp.factory('redirectInterceptor', ['$location', '$q', function($location, $q) {
return function(promise) {
promise.then(
function(response) {
if (typeof response.data === 'string') {
if (response.data.indexOf instanceof Function &&
response.data.indexOf('<html id="ng-app" ng-app="loginApp">') != -1) {
$location.path("/logout");
window.location = url + "logout"; // just in case
}
}
return response;
},
function(response) {
return $q.reject(response);
}
);
return promise;
};
}]);
Then insert this interceptor to your app. something like this:
$httpProvider.responseInterceptors.push('redirectInterceptor');
good luck.
Your 302 -Redirect is being handled directly by the browser and there is nothing you can do about it directly. You can, however, use an httpInterceptor to help you along. You'll need to include $httpProvider in your app DI list, and then somewhere in your config function put a reference to it like this:
$httpProvider.responseInterceptors.push('HttpInterceptor');
A sample interceptor looks like this:
window.angular.module('HttpInterceptor', [])
.factory('HttpInterceptor', ['$q', '$injector',
function($q, $injector) {
'use strict';
return function(promise) {
return promise.then(success, error);
};
function success(response) {
return response;
}
function error(response) {
var isAuthRequest = (response.config.url.indexOf('/v1/rest/auth') !== -1);
//if we are on the authenticating don't open the redirect dialog
if (isAuthRequest) {
return $q.reject(response);
}
//open dialog and return rejected promise
openErrorDialog(response);
return $q.reject(response);
}
function openErrorDialog(response) {
$injector.get('$dialog').dialog({
backdropFade: true,
dialogFade: true,
dialogClass: 'modal newCustomerModal',
resolve: {
errorData: function() {
return response.data;
},
errorStatus: function() {
return response.status;
}
}
})
.open('/views/error-dialog-partial.htm',
'errorDialogController')
.then(function(response) {
if (response) {
window.location = '/';
}
});
}
}
]);
I had a very similar issue, and considered the solution provided by Ofer Segev, but checking the content of the response to see if it matched an html fragment of another page just seemed too hacky to me. What happens when someone changes that page?
Fortunately, I had control of the backend as well, so instead of returning a 302 (Redirect), I returned a 403 (Forbidden), and passed the desired location in the headers. Unlike the 302, the 403 will be handled in your error handler, where you can decide what to do next. Here was my resulting handler:
function ($scope, $http) {
$http.get(_localAPIURL).then(function (response) {
// do what I'd normally do
}, function (response) {
if (response.status == 403)
{
window.location.href = response.headers().location;
}
else
{
// handle the error
}
As discussed above, 302 responses are not available to Angular as xmlHttpRequest does not support returning redirects; the browser acts before you can do anything about it.
In addition to processing custom data responses and overriding status codes,
you could use a more generic solution and add a custom redirect header, such as X-Redirect and act upon that. The value of X-Redirect should be the url you want to redirect to eg https://other.url.com/globalLoginPage.html
$http.get(orig_url).then(function(response) {
// do stuff
}, function (response) {
var headers = response.headers();
if ('x-redirect' in headers)
{
document.location.href = headers['x-redirect'];
}
return response;
}
}
For a more global solution, you could also use a HTTP Interceptor
app.factory('myHttpInterceptor', function ($q, myCache) {
return {
request: function (config) {
return config;
},
response: function(response){
var headers = response.headers();
if ('x-redirect' in headers)
{
document.location.href = headers['x-redirect'];
}
return response;
},
responseError: function(rejection) {
switch(rejection.status)
{
case 302:
// this will not occur, use the custom header X-Redirect instead
break;
case 403:
alert.error(rejection.data, 'Forbidden');
break;
}
return $q.reject(rejection);
}
};
});
You can set the custom header server side.
For example, if you are using PHP Symfony:
$response = new Response('', 204);
$response->headers->set('X-Redirect', $this->generateUrl('other_url'));
return $response;
来源：https://stackoverflow.com/questions/18737674/handle-http-302-response-from-proxy-in-angularjs