Enforce Permission for Facebook's JS-SDK - facebook

My login code looks like so:
FB.login(statusChangedHandler, {
scope: 'email,'
});
I would like to enforce the email permission in such way that a user who
disabled it would not have the ability to login to the app - he will get an
error message and be prompted to login again.
Is there any built-in (Facebook's) method of doing such a process?

You can´t enforce it, you can only check after the authorization. An easy way is to use return_scopes, as you can read in the docs: https://developers.facebook.com/docs/reference/javascript/FB.login/v2.3#permissions

Related

React-Native-fbsdk read and publish

I use react-native-fbsdk to login my users into my application like that :
LoginManager.logInWithReadPermissions(["public_profile", "email", "user_birthday", "user_location", "user_about_me"])
But i need to permit to my users to share some informations to their facebook feed ! So i need to have 'publish_actions' permissions and it's not working with 'logInWithReadPermissions' and, i can't set read permissions with 'logInWithPublishPermissions' !
So how can i do that ?
Thanks!
There is a logInWithPublishPermissions function too: https://github.com/facebook/react-native-fbsdk/blob/master/js/FBLoginManager.js
...although, you should consider using the Share Dialog, it does not need publish_actions: https://github.com/facebook/react-native-fbsdk
Make sure you don´t ask for read and write permissions at the same time, you only need write permissions just before the user wants to share something anyway, not when he logs in.

How to simply use facebook login for my app without using the SDKs?

Is there a simple flow (hello world) for a user to login using facebook?
Found documentation on Manually Build a Login Flow, but is too full of text and details that I don't see the main flow.
Based on Manually Build a Login Flow (showing only the minimal data needed to make it work):
Create a facebook app.
Simulate the user clicking on the following authentication URL to allow the app to access the user's data: https://www.facebook.com/v2.8/dialog/oauth?client_id=<app id>&redirect_uri=http://localhost/
Click ok/accept/whatever to authorize access.
You get redirected by facebook to a URL of the following: http://localhost/?code=<code>
Take the code and invoke the following: curl 'https://graph.facebook.com/v2.8/oauth/access_token?client_id=<app id>&redirect_uri=http://localhost&client_secret=<app secret>&code=<code>'
You get a result like the following: {"access_token":"<access token>","token_type":"bearer","expires_in":5183924}
You can then use the access token to call API related to the user that gave the permissions to your app. Example: curl 'https://graph.facebook.com/v2.8/me?access_token=<access token>'
Example response: {"name":"Alik Elzin","id":"<app related user id>"}
* Remember to add http://localhost/ to the app's Valid OAuth redirect URIs - under app settings.
Have you checked out this documentation from Facebook? It's pretty short to read through: https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow

Loose req.session when trying to get more FB privileges via everyauth

I've been doing user authentication with everyauth and Facebook and all works well. Now, I want to integrate an ability to post to Facebook. Since my app asks only for email scope when users first login, I'll need to get a larger FB scope, and am trying to follow the FB guidelines and only ask for this additional scope when I need it.
I added the following code to my everyauth configuration as per the docs:
everyauth
.facebook
.appId(conf.fb.appId)
.appSecret(conf.fb.appSecret)
//TODO add custom redirect for when authentication is not approved
.scope(function (req, res) {
console.log('Setting FB scope');
console.log('Session: ' + util.inspect(req.session));
var session = req.session;
switch (session.userPhase) {
case 'share-media':
return 'email,user_status';
default:
return 'email';
}
})
All is well when an unauthenticated user logs into the application. The problem is that when I want to "up the ante" on FB scope, which I do by setting req.session.userPhase to 'share-media', and then present a link to /auth/facebook to confirm they want to allow posting to FB. When this happens, I get an error that req.session is undefined from the above code (all of req is undefined).
I assume this is since a previously logged-in user is essentially re-authenticating, but isn't that how I would get more scope from Facebook? Am I going about this the wrong way?
Thanks!!!

Facebook on/off social reading in app

I try social plugin "Recommendations Bar" and it works. It has a built-in function to activate and deactivate the social reading function.
I want to enable this function in my simple app with "read" publish_actions.
I don't want to use cookies or session var to do this, it's a wrong way.
Users have to choose in which article on/off the social reading and change his preference on the fly.
User login with:
scope="publish_actions, email"
I know:
$facebook->api("/me/permissions");
$facebook->api("/me/news.reads?limit=10");
and I can post reads:
FB.api('/me/news.reads',
'post',
{ 'article': 'xxxxxx',
'access_token': 'xxxxx' },
function(response)
and delete it:
FB.api(id, 'delete', function(response)
Any idea for API call to enable/disable social reading function?
How to set publish_actions permission value to 0/1 for the users having app installed?
I dont want to use cookies or session var to do this, it's a wrong way.
Right, the user’s profile would be a better place to save this, so that he doesn’t have to make that decision again next time he visit’s your site.
How to set publish_actions permission value to 0/1 for the users having app installed?
You can’t revoke permissions via app. And I can’t see why you would want to. If a user disabled social reading on your site (which you save in their profile, preferably), then just don’t post anything on their behalf.

Extend auth token without refreshing the page

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 )