I am building an application that does not have a client interface.
At the setup step: The user logs into the server throught a browser once using oauth, and the server makes sure that the client is identified.
From this point on, no browsers are invlovled. It all happens in the background.
It then keeps acting on behalf of the user for as long as the user can be validated.
That means that once in a while, my server needs to call the oauth provider to validate the user still exists.
Until now, I have only used google oauth: Once in a while, I would call the refreshtoken api, and get a new token indefinitely from the server side. (you need to ask for "offline access" when you get the user token).
Now I would like to use facebook as well, but reading their APIs, I see no mention of a possibility for a server to refresh it's tokens:
https://developers.facebook.com/docs/facebook-login/access-tokens/refreshing/
It looks like it all has to be done from the client device.
As I have no client device, does this mean that I cannot write this sort of app with facebook?
I think your scenario can be covered through Facebook's mechanism. But you need to support a re-login if some error occur while using long lived access token. This can happen due to security measure taken by Facebook (ex:- data breach, cryptographic breach) or when user revoke tokens or change password or when tokens are not used for a longer time.
Steps to follow (According to their docs),
Obtain a User access token
These are short lived
Short-lived tokens usually have a lifetime of about an hour or two
Exchanging Short-Lived Tokens for Long-Lived Tokens
These have life span of around 60 days, even when they are not used.
long-lived token generally lasts about 60 days.
Basically, once you obtain a long lived token, you can use it from the server application. During this process, you required a client which used browser only to obtain short lived access token.
But as previously mentioned, these tokens can expire,
These tokens are refreshed once per day, when the person using your app makes a request to Facebook's servers. If no requests are made, the token will expire after about 60 days and the person will have to go through the login flow again to get a new token.
So you will require to obtain new ones by going through above two steps.
According to the Facebook docs, mobile SDKs generate long lived tokens which are refreshed once per day when the person using your app makes a request to the Facebook servers. For the javascript SDK, short-lived tokens are generated and are refreshed periodically.
I'm curious as to what is meant by "the person using your app makes a request to the Facebook servers". Which calls specifically will cause the token to be refreshed? Or more importantly, which calls won't? Is it enough to check the login status or is something more active required? What I'm really interested in is keeping the token alive (or getting a new one) without sending the user back through the login flow, or doing anything that's particularly active with Facebooks APIs.
Thanks!
According to Facebook SDK Docu
Once a token expires ("auto" extend of Facebook SDK Token)
At any point, you can generate a new long-lived token by sending the person back to the login flow used by your web app - note that the person will not actually need to login again, they have already authorized your app, so they will immediately redirect back to your app from the login flow with a refreshed token
THERE IS no keep alive functionality in Facebook SDK.
User access tokens come in two forms: short-lived tokens and long-lived tokens. Short-lived tokens usually have a lifetime of about an hour or two, while long-lived tokens usually have a lifetime of about 60 days. You should not depend on these lifetimes remaining the same - the lifetime may change without warning or expire early. See more under handling errors.
long-lived = 60 days
Short-lived = 2 hour
Also according to Facebook SDK Docu
Mobile apps that use Facebook's mobile SDKs get long-lived tokens.
Once you force a user for a new oAuth/login, he will receive a new token. The old one will not expire. You are able to check the loginStatusby FB.getLoginStatus. No need for a keep alive.
The SDK will refresh the access token for you when an actual graph request is made (up to once a day). Any time the token is updated, the AccessTokenTracker will be notified, so you can register a tracker if you want to be notified of updates (e.g. for sending to the server).
If you only make graph requests from your server, then you'll need to handle expiration from there, and either try to extend, or prompt your user to do SSO again to get an updated token.
I'm using the URL below to get the auth token:
https://www.facebook.com/dialog/oauth?client_id=CLIENT_ID&redirect_uri=RETURN_URL&scope=manage_pages,publish_stream
This page will redirect to another URL with the code token in query string. I'm using this code token to get the Page access token automatically and publish to the Page 'offline'.
In recent days, it seems that Facebook has changed the expiration time of this token code.
I am able to use this token once. The time expiration is very short. Anyone know if there really was a change in facebook? Is there any other alternative to work with this?
This was part of the December 5th changes on the Roadmap: the code can only be exchanged for an access_token once and must be exchanged within 10 minutes of generation.
New security restrictions for OAuth authorization codes We will only
allow authorization codes to be exchanged for access tokens once and
will require that they be exchanged for an access token within 10
minutes of their creation. This is in line with the OAuth 2.0 Spec
which from the start has stated that "authorization codes MUST be
short lived and single use". For more information, check out our
Authentication documentation.
If you're unsure how to log users in correctly because you were relying on the old, incorrect behaviour, ensure you're using the newest SDKs and read the Login documentation in detail, specifically the Server Side Login documentation which shows how to exchange the code for a token
Once you have the token, save it using whatever session storage mechanism your app uses (PHP SDK will store it in a PHP session for you) and use the access token on subsequent calls instead of trying to obtain a new access_token from the code
I'm able to get an access token that's good for 60 days, but I'm not able to get the expiration time extended. I'm doing this to be able to get access to Facebook pages through a single user. Here's my process.
I make a call to:
https://www.facebook.com/dialog/oauth?response_type=token&client_id=APP_ID&scope=read_stream,publish_stream,manage_pages,read_insights,create_event&redirect_uri=REDIRECT_URL
I then call to this URL using the token I got from the URL above:
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
I've tried this multiple times over the weekend, and in every single instance, I get the same access token, but the expiration is not updated. I've done this by accessing the URLs in my browser.
Am I missing anything to be able to renew the expiration?
I think the page admin user will have to come back to your app in that 60 days to get a new access token with the extended time on it. I don't think you can (or should) be allowed to extend the access token by application only.
See: https://developers.facebook.com/docs/offline-access-deprecation/
Note: The user must access your application before you're able to get
a valid "authorization code" to be able to make the server-side oAuth
call again. Apps will not be able to setup a background/cron job that
tries to automatically extend the expiration time, because the
"authorization code" is short-lived and will have expired.
I just encountered this problem. The issue ended up being that "deprecate offline access" was disabled in my FB application. When disabled, the extending tokens always returned a short lived token. When enabled, I was able to get long lived access tokens.
The offline access has been deprecated by the facebook developers, but you can still extend your access token life upto 60 days by passing your app id, app secret and current access token to the following url:
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
Note: The EXISTING_ACCESS_TOKEN must be a valid accesss token(not expired one).
I am playing around with the Oauth 2.0 authorization in Facebook and was wondering if the access tokens Facebook passes out ever expire. If so, is there a way to request a long-life access token?
After digging around a bit, i found this. It seems to be the answer:
Updated (11/April/2018)
The token will expire after about 60 days.
The token will be refreshed once per day, for up to 90 days, when the person using your app makes a request to Facebook's servers.
All access tokens need to be renewed every 90 days with the consent of the person using your app.
Facebook change announce (10/04/2018)
Facebook updated token expiration page (10/04/2018)
offline_access:
Enables your application to perform authorized requests on behalf of the user at any time. By default, most access tokens expire after a short time period to ensure applications only make requests on behalf of the user when the are actively using the application. This permission makes the access token returned by our OAuth endpoint long-lived.
Its a permission value requested.
http://developers.facebook.com/docs/authentication/permissions
UPDATE
offline_access permission has been removed a while ago.
https://developers.facebook.com/docs/roadmap/completed-changes/offline-access-removal/
Try this may be it will help full for you
https://graph.facebook.com/oauth/authorize?
client_id=127605460617602&
scope=offline_access,read_stream,user_photos,user_videos,publish_stream&
redirect_uri=http://www.example.com/
To get lifetime Access Token you have to use scope=offline_access
Meaning of scope=offline_access is that :-
Enables your application to perform authorized requests on behalf of
the user at any time. By default, most access tokens expire after a
short time period to ensure applications only make requests on behalf
of the user when the are actively using the application. This
permission makes the access token returned by our OAuth endpoint
long-lived.
But according to facebook future upgradation the offline_acees functionality will be deprecated for forever from the 3rd October, 2012.
and the user will be given 60 days long-lived access token and before expiration of the access token Facebook will notify or you can get your custom notification functionality fetching the expiration value from the Facebook Api..
Note that Facebook is now deprecating the offline_access permission in favor of tokens for which you can request an "upgrade" to the expiry. I'm just now dealing with this, myself, so I don't have much more to say, but this doc may help:
https://developers.facebook.com/docs/offline-access-deprecation/
I came here with the same question as the OP, but the answers suggesting the use of offline_access are raising red flags for me.
Security-wise, getting offline access to a user's Facebook account is qualitatively different and far more powerful than just using Facebook for single sign on, and should not be used lightly (unless you really need it). When a user grants this permission, "the application" can examine the user's account from anywhere at any time. I put "the application" in quotes because it's actually any tool that has the credentials -- you could script up a whole suite of tools that have nothing to do with the web server that can access whatever info the user has agreed to share to those credentials.
I would not use this feature to work around a short token lifetime; that's not its intended purpose. Indeed, token lifetime itself is a security feature. I'm still looking for details about the proper usage of these tokens (Can I persist them? How do/should I secure them? Does Facebook embed the OAuth 2.0 "refresh token" inside the main one? If not, where is it and/or how do I refresh?), but I'm pretty sure offline_access isn't the right way.
Yes, they do expire. There is an 'expires' value that is passed along with the 'access_token', and from what I can tell it's about 2 hours. I've been searching, but I don't see a way to request a longer expiration time.
since i had the same problem - see the excellent post on this topic from ben biddington, who clarified all this issues with the wrong token and the right type to send for the requests.
http://benbiddington.wordpress.com/2010/04/23/facebook-graph-api-getting-access-tokens/
You can always refresh the user's access token every time the user logs into your site through facebook.
The offline access can't guarantee you get a life-long time access token, the access token changes whenever the user revoke you application access or the user changes his/her password.
Quoted from facebook http://developers.facebook.com/docs/authentication/
Note: If the application has not requested offline_access permission, the access token is time-bounded. Time-bounded access token also get invalidated when the user logs out of Facebook. If the application has obtained offline_access permission from the user, the access token does not have an expiry. However it gets invalidated whenever the user changes his/her password.
Assume you store the user's facebook uid and access token in a users table in your database,every time the user clicks on the "Login with facebook" button, you check the login statususing facebook Javascript API, and then examine the connection status from the response,if the user has connected to your site, you can then update the access token in the table.
Hit this to exchange a short living access token for a long living/non expiring(pages) one:
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
log into facebook account and edit your application settings(account -> application setting ->additional permission of the application which use your account). uncheck the permission (Access my data when I'm not using the application(offline_access)). Then face will book issue a new token when you log in to the application.
Basic the facebook token expires about in a hour. But you can using 'exchange' token to get a long-lived token
https://developers.facebook.com/docs/facebook-login/access-tokens
GET /oauth/access_token?
grant_type=fb_exchange_token&
client_id={app-id}&
client_secret={app-secret}&
fb_exchange_token={short-lived-token}
This is a fair few years later, but the Facebook Graph API Explorer now has a little info symbol next to the access token that allows you to access the access token tool app, and extend the API token for a couple of months. Might be helpful during development.
check the following things when you interact with facebook graph api.
1) Application connect URL should be the base of your "redirect_uri"
connect URL:- www.x-minds.org/fb/connect/
redirect_uri - www.x-minds.org/fb/connect/redirect
2) Your "redirect_uri" should be same in the both case (when you request for a verification code and request for an access_token)
redirect_uri - www.x-minds.org/fb/connect/redirect
3) you should encode the the argument when you request for an access_token
4) shouldn't pass the argument (type=client_cred) when you request for an access_token. the authorization server will issue a token without session part. we can't use this token with "me" alias in graph api. This token will have length of (40) but a token with session part will have a length of(81).
An access token without session part will work with some cases
eg: -https://graph.facebook.com/?access_token=116122545078207|EyWJJYqrdgQgV1bfueck320z7MM.
But Graph API with "me" alias will work with only token with session part.
I don't know when exactly the tokens expire, but they do, otherwise there wouldn't be an option to give offline permissions.
Anyway, sometimes requiring the user to give offline permissions is an overkill. Depending on your needs, maybe it's enough that the token remains valid as long as the website is opened in the user's browser. For this there may be a simpler solution - relogging the user in periodically using an iframe: facebook auto re-login from cookie php
Worked for me...