I am building a facebook app with codeigniter. When a user accepts a request and gets redirected to my app I want to store the request_id in a session. At first it gets stored but when the page is reloaded after the user authenticates the app the requested_id stored earlier doesn't exist anymore.
function save_request_id()
{
$this->session->set_userdata('request_id', $request_id);
}
function retrieve_request_id()
{
$data = $this->session->all_userdata();
print_r($data);
exit;
}
You want to only retrieve the request_id:
$this->session->userdata('request_id');
Sounds like the session is being cleared when the user completes the auth cycle. Are you using the FB PHP SDK? If so, I believe it creates its own session to manage the connected user. Check the library you're using, you may need to adjust it to fit your needs - or devise an alternate solution, like redirecting after auth to a view that can process a request_id in the URL.
session library of CodeIgniter has this problem,use native php session + secuirty lib of CodeIgniter to clean XSS .
Related
I'm utilizing the Facebook PHP SDK on its own. I do not want to use the JS SDK at all.
Because getUser(); from the SDK can return a user id even if the user is not logged in, I have opted for using a try/catch statement to check if the user is logged in.
try
{
$me = $CI->facebook->api('/me');
$CI->our_fb['is_fb']='YES';
echo "hello";
}
catch(FacebookApiException $e)
{
echo "catch";
}
This statement is included in the global include file of all of my files (for simplicity).
So, depending on the situation, I generate a Facebook login URL. The expected functionality is that the user logins to Facebook, authorises the app, is returned to the redirect URI set in the login URL at which point the try statement will execute, and $CI->our_fb['is_fb'] will be set.
This is however not happening.
If the user is already logged into Facebook and the app is authorised, it works perfectly. SUCCESS
If the user is not logged into Facebook, once redirected the variable is not set. FAILURE
If the user is logged in but the app is NOT authorised after redirect the variable is not set. FAILURE.
In the latter two cases if you simply refresh the page, the variable is set - SUCCESS. Refreshing the page is however unnecessary/pointless extra effort.
My problem is that if you need to login to FB/or authorise the app e.g the first time you login with FB, you have an additional unneeded refresh, and I don't know why.
I suspect it is something to do with the cookie/session? Which saves the access token that I assume is returned/passed to the SDK automatically not being set at the same time?
Anyone got any ideas?
If you're having an app on facebook (tab or canvas). PHP SDK only get the User ID on initial loading of a page because a signed_request is sent with the request to your app.
But, when the app refreshes, the signed_request is lost (as it's facebook who send it).
So, in this case, you can append the signed_request to every URLs your use in your app - but that's really not optimal as the signed_request won't be regenarated - neither refreshed.
Your only real option is to rely on the JS SDK to set cookie correctly and allow getUser to work as expected. This is required because you're considered as a third-party app in Facebook (being in an iframe) and most browser will block you from setting cookies - so you need a work around handled by the JS SDK for you. You can search for cross-domain cookies or third-party cookie for explanation about the workarounds, but these workaround only work via JS scripting and iframe management.
Also, be sure to setup the JS SDK correctly: channel file, cookie allowed, and send P3P headers (for IE).
You can also check this related question: A proper approach to FB auth
About website, the same mostly stays (but you have no signed_request). At this point, seriously consider using the JS SDK as it's way easier. Or else, you can make sure your app flow follow these guidelines: https://developers.facebook.com/docs/concepts/login/login-architecture/
The way I am seeing this is, you are trying to avoid that refresh if the user is not logged in and precedes to log in after the page has initially loaded.
So what you can do is make an ajax request to another page on your site, say for example id.php, which just loads the php sdk and echo $userid; and then you can grab the user id after login without the refresh.
Basically the cookie is used to save the signed request and session is used to save 'state', 'code', 'access_token', 'user_id'. If the above are present PHP SDK uses them, no matter if they are valid or not.
I think your problem lies in the CODE sent by facebook. Specifically these lines in base_facebook.php:
if ($code && $code != $this->getPersistentData('code')) {
$access_token = $this->getAccessTokenFromCode($code);
...
protected function getAccessTokenFromCode($code, $redirect_uri = null) {
if (empty($code)) {
return false;
}
if ($redirect_uri === null) {
$redirect_uri = $this->getCurrentUrl();
}
...
Because CODE is issued for specific url sometimes there is such situation: Visitor arrives on www.example.com. He givies permissions and is redirected to example.com/login. But the code is not valid there, so the getUserAccessToken returns false. When you refresh the page you get same urls and everything's fine.
You're on the right track of not using getUser() because as I wrote above it's taken from the session if available.
I am developing iPhone application which loads login page of my website. I am able to load my login page using phonegap/childbrowser. I am newbie to JS, Phonegap.
How do my native/phonegap application should handle logout and login event has performed on the webpage? Please guide me how to know user has logged out.
Also is it possible to add support for Push Notification in phonegap/childbrowser application ? How?
So far have seen facebook login-logout questions around but hard to understand and couldnt simulate similar approach.
does your whole app run using the childbrowser? If so why not just have the login log out as piece of your app?
Also if you have to use the childbrowser best bet is to set up a locationchange event and if the location equals a login success page then append some arguments and store those using localstorage.
example -
client_browser.onLocationChange = function(loc){
locationchange(loc);
};
function locationchange(loc){
if(loc.indexOf("http://www.example.com/success?login=true&user=foo") > -1){
var user = loc.match(/user=(.*)$/)[1]; // grab user info
localStorage.setItem('login','true'); // set login as true
localStorage.setItem('user',user); // set username
}
}
that will save to your app locally that the user is logged in and their username, which you can use later if you need to use the childbrowser by passing that in the url you open and on the server side you'll have to look for those arguments.
to log out just open the childbrowser and send a logout argument
www.example.com/logout?user=foo
and in your localStorage
localStorage.setItem('login','false');
Honestly this is kind of a vague question, it would really help to understand why you're wanting to do this in the childBrowser vs your app...
Users want to use my facebook app for many hours without refreshing the browser.
But token expires in 2 hours. Now I ask users to refresh the page but that's annoying.
I don't want to ask offline access permissions because it will scare some users.
The best solution will be somehow "relogin" and get new token without refreshing the page.
Is it possible?
I would subscribe to the expiry trigger (I think this is authResponseChange), then automate another login check. It won't be a perfect solution as it could trigger a pop up (if they have logged out for example) automatically, which a lot of browsers may block. You could instead, when the token expires, check if they will need to complete a pop up, and display a notification on your page somewhere saying 'Facebook needs your attention to continue', then only launch the pop up from their response, which would stop the pop up being blocked.
FB.Event.subscribe('auth.authResponseChange', function(response) {
// do something with response
FB.login(){
// refresh their session - or use JS to display a notification they can
// click to prevent pop up issues
}
});
An algorithm to workout on this
Ask for permission from the user
Save the token
Periodically check for an access token is near to expire or not
If its in verse of expiry, embed some dummy iframe, which redirects to the facebook homepage. - Extend auth token without refreshing the page
This should refresh the token. You might need to generate another token or continue with the same. Whatever be required, can be done without refreshing the page.
Have you thought of using ajax? After two hours you will check, if user is still active. If so, you send axax request to URL, where his session details will be updated. example:
$(document).ready(function(){
setInterval('update_session()', 5500000);
})
update_session(){
$.post({
URL: ..., // script to update session on server
data:{ /* username, password */ },
})
}
and the server-side just takes username and password from post or and runs relogin.
Try acquiring tokens with the offline_access permission.
I presume, guess this is not possible,FB architecture would not allow it. And why is offline_access such a problem!!!!!!...anyway offline_access is the best optimal solution I guess....
Unfortunately I believe this is impossible by design (if you mean for it to happen without user intervention). If the user is still logged in to Facebook you can redirect the top-level page to Facebook and it will bounce you right back with a new code (as it sounds like you are doing already), but that is only possible because of the Facebook cookie that it can check. If you try to do anything from your server, it will be rejected because that cookie will not accompany the request. Same goes for trying to make a call to facebook from javascript -- since your code is running in a different domain, the cookie will not accompany the call and Facebook will reject it. The only way that Facebook can even know who the user is, and that they are still logged in, is to see that cookie. And the only way that can happen is if the browser itself is redirected to the facebook.com domain.
It's worth mentioning also that Facebook has blocked the only logical workaround, i.e. loading the oauth url in an iframe. If you try it you will see that they detect the page is being loaded in an iframe and output a page with a link on it which does a top-level redirect to break out of the frame. So not only does this approach not work, it's clear that Facebook has specifically made it impossible as part of their architecture.
Edit: If what you mean to do is not avoid the refresh altogether but just have it happen automatically when a new token is needed, you can do something like this:
$status=0;
$data=#file_get_contents("https://graph.facebook.com/me?access_token=$token");
foreach ($http_response_header as $rh) if (substr($rh, 0, 4)=='HTTP') list(,$status,)=explode(' ', $rh, 3);
if ($status==200)
{
//token is good, proceed
}
else
{
//token is expired, get new one
$fburl="http://www.facebook.com/dialog/oauth?client_id=APP_ID&redirect_uri=".urlencode('http://apps.facebook.com/yourapp/thispage.php');
echo "<html>\n<body>\n<script>top.location='$fburl';</script>\n</body>\n</html>\n";
exit;
}
This is assuming you have something before this code that will process a signed_request parameter if it is present and assign a value to $token (either explicit code of your own or the appropriate SDK entries). The shown code can then be used anywhere you need to check if $token is still valid before proceeding.
If you get the access_token without specifying any expiry to them they will not expire ..
atleast not till the time user either changes his Fb credentials or de registers your application ..
I presume you are using the iframe signed_request parameter to get your access token. One method of achieving what you require is to use the oAuth 2.0 method of aquiring an access token. This is more prolonged in the first instance; your server and Facebook's have to exchange credentials which can be slow, but it means that you will be given a code that can be exchanged for an access token regularly, meaning your server can maintain the session periodically (probably from an ajax call from the client). You would then pass this new access_token to the client, and use it in your dialog call for your requests (gifts).
Hope that helps.
Spabby
Have a look at https://developers.facebook.com/docs/offline-access-deprecation/#extend_token
basically you extend the token with
https://graph.facebook.com/oauth/access_token?
client_id=APP_ID&
client_secret=APP_SECRET&
grant_type=fb_exchange_token&
fb_exchange_token=EXISTING_ACCESS_TOKEN
that will give you new token with new expiry time (it should be 60d but I'm noticing similar bug like described here https://developers.facebook.com/bugs/347831145255847/?browse=search_4f5b6e51b18170786854060 )
I'm developing using the Facebook PHP SDK.
I wanted to make it so that when the user logs out of Facebook, they will automatically be logged out of my website too.
I am using the following code to detect the session, using the session cookie:
$facebook->getUser();
For some reason, the getUser() function still returns the user's Facebook ID, even after they have logged out of Facebook on their website.
Am I to detect the session first using another Function?
On the official documentation example here, is the following excerpt from their comments:
// Get User ID
$user = $facebook->getUser();
// We may or may not have this data based on whether the user is logged in.
//
// If we have a $user id here, it means we know the user is logged into
// Facebook, but we don't know if the access token is valid. An access
// token is invalid if the user logged out of Facebook.
This lead me to believe that the session cookie for Facebook would become unset upon Facebook logout?
Kind Regards,
Luke
I have the same issue!
The FB PHP SDK saves those things into the $_SESSION!
You can delete them like this when your user clicks logout:
$_SESSION['fb_'.APP_ID.'_user_id'] = '';
$_SESSION['fb_'.APP_ID.'_access_token'] = '';
Although this is not the final solution, it works for now.
I appreciate comments and solutions on that!
I want to give an alternative, in a way you don't have to handle session stuff. Although, I must warn you this is slower than cleaning up the session, because it relies on a new request. What we're doing in the code below is to check on Facebook if the token is still valid. Here it's:
try {
$facebook->api('/me','GET');
$logged = true;
} catch(FacebookApiException $e) {
$logged = false;
}
In my case, I was doing everything using the JavaScript SDK, so I couldn't clean session on logout. But in my landing page, I was needing a work around to check it before send the response back.
If you're facing something like this, definitely a good solution.
The problem seems to be in php-sdk in basefacebook.php at line 567
protected function getSignedRequestCookieName() {
return 'fbsr'.$this->getAppId();}
This method returns the name of the cookie the sdk is looking for. However, javascript-sdk uses 'fbs_' prefix. Change this to 'fbs_' and it works fine.
return 'fbs'.$this->getAppId();}
$facebook->destroySession();
To destroy the session you can also use:
$facebook->destroySession();
I looked around and could not find anything to do this (well it was not obvious or semi-obvious)
So say i have a facebook application that offers a service that people will pay for during use. The average user can come on and "Subscribe" to it, while the admin of those pages can perform an activity that will cost them money (make me money).
I do not want hacking attempts or anything to hurt our product. So, how can i verify that someone is an admin using the PHP SDK.
What we are currently doing is storing the $_POST["signed_request"] in $_SESSION's data and working with that. Either the $_POST or $_SESSION is not safe 100% (firesheep).
Is there any way to verify this? graph api?
Okay, first things first. To retrieve the signed_request and check if the user is an admin you would use something like:
$signed_request = $facebook->getSignedRequest();
if ($signed_request['page']) { // Loaded in a page tab
if ($signed_request['page']['admin']) {
// Current user is admin
} else {
// Normal user
}
} else { // Canvas view
}
Now I'm not sure what do you mean by:
What we are currently doing is storing the $_POST["signed_request"] in
$_SESSION's data and working with that.
Because if you are using the PHP-SDK then you don't need to worry about storing the signed_request in the session since the SDK will handle it for you.
Now for the last part:
Either the $_POST or $_SESSION is not safe 100% (firesheep).
That's not true, the signed_request is useless without your app secret key to decode it. So even if someone was able to obtain it, it won't compromise your application. Read more about signed_requests here.