when I do a get request to
https://graph.facebook.com/[userid]
with the access_token i get all the basic info
but when I do
https://graph.facebook.com/me
with the same token i get an error message: An active access token must be used to query information about the current user
I have tried to under stand what can cause that.
I even tried to token that comes with the signed request
I'm on classic asp, with JSON library, I want the auto to be server side if possible. the FB.api("/me" is working but it is not what i really want to achive
I am pretty sure you don´t have a user access token. Did you login the user? Of course you get the public data of every user with your first link, even without any access token. You can even put it directly in the browser and will get results. But for "/me" you have to authorize the user to your app.
See here: https://developers.facebook.com/docs/howtos/login/server-side-login/
It is the same problem as in the other thread for sure, just a different Programming language.
Remember: If the user did not accept at least the basic permissions in a dialog or redirect, he is not logged in and you will never know anything about him in the app (except for some specifics in tab apps, like language, like-status and stuff).
Related
I am the administrator of a Facebook Page. I am building a web app which, under certain circumstances, will post on Facebook as that Page.
With most APIs, I would just get an API key, and supply that when connecting to the API from my app. But Facebook expects an access token instead of an API key. (Specifically, in this case, it needs a "page access token".)
I am trying to figure out how to get a page access token that will be as permanent as possible.
After jumping through a bunch of esoteric, undocumented hoops (see here and here) in order to get a token that wouldn't expire, I had this working. When I ran the token through Facebook's Access Token Debugger, the "Expires" field read "Never". All was good in the world.
But, the next day, my token became invalid anyway. The Access Token Debugger, and my app's calls to Facebook's PHP SDK, both started returning this error:
Error validating access token: Session does not match current stored session. This may be because the user changed the password since the time the session was created or Facebook has changed the session for security reasons.
It seems that a token can become invalid for a variety of reasons (but this article is five years old, so who knows – Facebook changes things every two weeks). I had not changed my password. (I might have logged out of Facebook, though.) Facebook offers no specifics about why this particular token might have become invalid.
I've also seen a few references to a permission called offline_access, but Facebook seems to have removed this.
I suppose my question is twofold:
In general, I've found Facebook token authentication to be incredibly brittle when calling the Facebook API from the server. The token system seems to be designed mainly to allow other users to grant (or revoke) various kinds of account access to my apps. But that's not what I'm doing – I'm trying to get a token that will let me post to a page that I own. And for that scenario, Facebook's aggressive invalidation of tokens becomes a serious liability. I can't launch my app if my access token (and therefore my Facebook integration) could randomly stop working at any moment, requiring me to generate a new token and update the app. This seems absurd. Is there an alternative method of authenticating to Facebook for my purposes?
If a page access token is, in fact, the best way to authenticate my app to Facebook in order to post as my Page: how can I ensure that my token doesn't spontaneously become invalid?
I hate developing for Facebook :/ Thanks for any insight you can offer.
Extended Page Tokens are valid forever. They only get invalidated if you change your password or if you change the App Secret of your App. There´s really no magic in it, checking if the Token is still valid is obviously not a bad idea but that´s up to you. For example, you can send yourself an automated Email when there is an error using the Token, so you can refresh it. But it will really just happen if you change your password.
Links:
https://developers.facebook.com/docs/facebook-login/access-tokens
http://www.devils-heaven.com/facebook-access-tokens/
I have a CMS application which needs a little component that allows an editor to select a facebook page post to display.
I've been going around facebook API and I don't fully understand what is the proper way of doing it.
This would be a server call, I would prefer not to have an access token because I am not making the request on behalf of any user.
I've tried using access_token=app_id|app_secret, but apparently that request requires an user session. So I went to the graph explorer and copied my access token. That worked fine initially but then I learned that they expire. I could get a long live token, but apparently those also expire eventually.
So, what is the best way of doing this? I think that using someones facebook access token for this is risky. The token could be revoked at any point breaking the feature in production. Can I achieve this without an user access_token? if I cant, how is this token normally managed?
Update:
Well actually the app_id|app_secret works, just not in every case. I created several pages for testing purposes and it doesnt work in any of them. Then I tried accessing a post from some brand pages (unrelated to my project) and they work ok. So my problem is configuring the page.
When I tried to access the post using app_id|app_secret I get:
(#100) Requires user session
Posts are public in all cases
I already tried to assign a vanity url to the page, no change
I think it's not possible to use just an App Access Token to get the Page Posts. Unfortunately the docs are not very clear on this IMHO:
https://developers.facebook.com/docs/graph-api/reference/v2.2/page/feed/#readperms
An access token is required to view publicly shared posts.
A user access token is required to retrieve posts visible to that person.
A page access token is required to retrieve any other posts.
I implement some facebook related stuff and accessing graph api for that pourposes. But for implement Integration testing I need a simple strategy to get access_token. So I create test user for that. How could I get access_token only with server side involved, without including browser in the chain. Ideally I just need to exchange login/password to the token.
Correct workflow loooks like this:
According the correct answer, there is special tests users provided by facebook.
To to be able to tests system properly you need to do the following flow
Get application access token
Request application's tests user's via "GET /{app_id}/accounts/test-users"
Parse response and extract access_tokens for each user from that response.
You can't exchange the login/password for an Access Token, but you can create test users programmatically. Have a look here:
https://developers.facebook.com/docs/graph-api/reference/v2.0/test-user
https://developers.facebook.com/docs/graph-api/reference/v2.0/app/accounts/test-users
How to get an access token with the right permissions for a test User
https://developers.facebook.com/docs/graph-api/reference/v2.0/user/permissions/
Short answer: You can´t.
Server side you can only get an App Access Token, Page Access Token or extend an existing Access Token.
So it depends on what you need to achieve, if you just want to get public stuff from a Facebook Page, even an App Access Token may be good enough. But you cannot create User Access Tokens server side.
It may be possible with real test users created via the Graph API itself though, see Tobis answer for links about that. But it is definitely not possible with username/password.
We're using the Facebook JS SDK to authenticate users to our application, then sending that information to the server back end to log our user into the application (we support multiple forms of authentication but we can only support FB using a client side flow).
FB is able to log in correctly, I'm able to authenticate the user and everything else, but there's one wrinkle that I'm not sure how to handle, and I'm having difficulty finding anything in the documentation about it. Facebook sends back an accessToken in addition to an id. My question is, how do I verify on the server side that the accessToken is correct for the given id? I want to make sure that the data the user sends us matches what Facebook sent them, and I can't imagine this is that out of the ordinary, yet I can't seem to find any documentation on it.
In the response from Facebook should be a signed_request string that can authenticate that the data is genuine with and decoded to yield the user id and an oauth token for the user.
Passing this along with the other response to your server-side code should allow you to validate everything pretty easily.
May I suggest this answer from another question! It uses try-catch. It is probably the only way to verify that the authentication and the permissions are valid! That's how they do in their examples
Facebook OAuthException: (#1)
I dont think facebook provides any other way of checking
I'm working on a site that is trying to handle realtime feed updates from its users' Facebook accounts. I have the basic stuff in place: the app is subscribed to "feed", and the user's login asks for read_stream and offline_access (just in case) permissions. My test users have logged into FB and granted those permissions, and, when one of those users adds (or removes) a status update, the callback specified in my site's subscription is pinged. So far, all's well.
Now -- as I understand it -- my callback has to call up to Facebook to get the user's feed, so that the callback can do whatever it's going to do with it. That's where I'm having problems -- finding the right access token to retrieve the feed:
I've tried doing this with the app's access token. This token is able to retrieve friend information (also included in the app's subscription and user permissions), but it won't get me the feed.
I've tried all sorts of ways to get the user's access token from inside the callback, but nothing is working. I'm guessing this is because it's not "logged into Facebook" the way that a user in a browser can be, but whatever. Bottom line is I haven't found a way to get this token.
(BTW, if I cheat -- get an access token for the user from Graph API Explorer and hard-code it into the callback, the callback works properly. This is no real solution, of course, but it at least establishes that the rest of my code is working.)
So how does this work? Can the app access token be made to work somehow? Is there in fact a way for the callback to get an access token for an arbitrary authorized user? There's gotta be a way to do this, or there would be no point for realtime feed notifications. Any clues out there? This is SERIOUSLY kicking my butt... Thanks!
You might want to look into this. Instead of taking permission for offline access, facebook now gives short-lived access tokens (2 hours) when the user logs in. These can be exchanged with long-lived access tokens (2 months). Check out this article on how to go about it.
https://developers.facebook.com/roadmap/offline-access-removal/
I've found a solution, perhaps: When the user logs in, I snag their offline_access-enabled access token and save it in the app with the rest of the user's data. Then when I get notified of an update to that user's feed, I can pull the token from the database and pass it over to FB as the token part of the /feed... call. And, it works. There is no doubt some error handling to be done, but I am currently bouncing back and forth between thinking that (a) this is exactly the right way to handle this and (b) it's a terrible hack that is just asking for trouble. I guess I'll see which of these is the case...
Ask for offline_access (as you do) and store the access token. This is exactly why offline_access and access tokens are there, to make requests to facebook in the name of that user. (a) is the right way to go. (a) is the way I do it.
Good luck
When the user is authenticated via OAuth Facebook returns an access-token, but it is valid for few hours. The validity of this token comes with it as token-expiry.
However, this token can be exchanged with a new extended token which is valid for around 60 days. User the following code to get new-token:
URL url=new URL("https://graph.facebook.com/oauth/access_token?grant_type=fb_exchange_token&client_id="+appId+"&client_secret="+clientSecretId+"&fb_exchange_token="+fb_exchange_token;
InputStream Istream=url.openConnection().getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(Istream));
String new_token= br.readLine();
Hope it helps!!