Get events from facebook - token expiration - facebook

I need to get the latest event from a fanpage/user and show it on a blog. Everything work well with the Graph API but the problem is, that I need a access_token (currently I use a access_token, generated from account).
But the problem is that the token expires (also the offline token).. what is the best way to do that?

For a fanpage event, you should be able to use the page access token of the given page to retrieve the data. This will be possible following scenario 5 in https://developers.facebook.com/roadmap/offline-access-removal/. As to a user's event, you can extend the token for two months at most also described here https://developers.facebook.com/roadmap/offline-access-removal/.
To get it working on your blog would not be easy as you would need a way to reauth the user every two months when the tokens expire.
Facebook has moved away from the concept of offline tokens because they present a huge security risk for users as they may forget about the application. If a user has not used your application in two months, it is reasonable for Facebook to remove user authorization of your app.

Related

Automate Facebook page access token generation

So I'm trying to obtain a list of posts from a Facebook page that I have created. After reading the documentation, I need to provide a user access token / page token to each API request in order to get the data. The documentation states that the user access tokens & page access tokens come in two variants:
Short life, expires within a few hours / days.
Long life, expires within 90 days.
The application I am building is a aggregated news (Facebook, twitter and Instagram) feed that will be displayed to users on my website.
From what I have read, the app tokens don't have an expiration but cannot access the pages API.
Do Facebook really expect application owners to remember to manually update their keys every 90 days in order to keep the applications working, or am I missing something that I can do to automate this?
If it is only about your Page, you are not missing anything, and there is no way to automate generating tokens - that would make expiration dates pointless. You can only send yourself a reminder before it expires. But: It can also expire if your change your Facebook Password, for example. It would be a good idea to implement a proper error handling so you get a message when the Token does not work anymore.
If it is about other Pages too, you can apply for Page Public Content Access and use an App Token that is valid forever.

Facebook Tokens - I created a never-expiring token, but how?

I have been trying to create a never-expiring Facebook Token (ideally programatically) and have not been able to do so, then, without really trying, on a different Facebook Application, I managed to create a token which, according to
https://developers.facebook.com/tools/debug/accesstoken?version=v2.5&q={TOKEN}
will never expire and I can't replicate it on any other Facebook Apps or for any other Facebook Tokens.
I can programatically (PHP) take the short lived token (1/2 hours) and extend it to 60 days, but I wanted to ideally get a never-expire token.
I guess I'm not asking how I managed to do it, but I can't find any explanation or documentation nor reason as to why I was able to achieve this for one token, but not any others.
Is it something in the App itself while it was created? Is there actually a way to get a never-expiring token, even though I've followed many of the guides online yet can only get a 1/2 hour token converted to 60 days?
Is there actually a way to get a never-expiring token
No, not really. Even what you think is a never-expiring token can expire - f.e. if the user who created it changes their account password.
I guess I'm not asking how I managed to do it, but I can't find any explanation or documentation nor reason as to why I was able to achieve this for one token, but not any others.
It is not documented, because Facebook wants you to use the 60 day tokens, when you app is acting on behalf of a personal user profile. They removed offline_access permission ages ago, specifically so that apps the user has long forgotten about can’t act on their behalf or still access their data any more.
So if you are writing an app that acts on behalf of users, you should really rather make do with the 60 day token - that should be enough for most cases.
Now what you are seeing with your token here, is a side effect of how Facebook has implemented extended page access tokens. Those do not have a default expiry - but they need to be invalidated when the user is removed as a page admin. Therefor, they are internally tied to the user token that was used to request the page token. User token gets invalidated - page access token becomes invalid together with it. And that in turn requires that the user token does not automatically expire after 60 days.
So, when you extend a user token that includes manage_pages permission, you will get an extended token with “unlimited” validity. But, again, that is a side effect of current implementation only, and can change in the future.

Facebook: Refreshing long-lived access token automatically

I'm storing long-lived access tokens for users of my application that have associated their Facebook accounts to it. Since the demise of the offline_access tokens, these long-lived tokens have an expiry date of "about 60 days." However, they can refresh themselves when the user interacts with Facebook. According to the documentation:
These tokens will be 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.
What I'd like to know is what constitutes making a request to Facebook's servers. Does the user have to log in to the Facebook website, mobile app, or use a Like button somewhere? Or does my application making a request on behalf of the user count as well?
Also, when the tokens are refreshed, are they refreshed for another 60 days? Or are they refreshed for a smaller duration?
I wasn't able to find these specific answers in the documentation or in other questions asked here, so thanks in advance to anyone who might have more details.
Every time you use Facebook SDK so it makes any Graph API call, tokens will be refreshed. You can see this in their source code, in AccessTokenManager there is function extendAccessTokenIfNeeded(), and that function is called inside GraphRequest in function executeConnectionAndWait().
You can also manually refresh tokens by calling:
AccessToken.refreshCurrentAccessTokenAsync();
I found one exception to this. Only sso tokens can be refreshed, which means if user logged in to your app via facebook app. If user logged in via browser, token will remain the same.
The previous line to the one you pasted is important:
Native mobile applications using Facebook's SDKs will get long-lived access tokens, good for about 60 days
The section you pulled out refers only to iOS and Android apps using the Facebook SDK - the SDK makes an API call to extend the token, which will only work from the SDK and for tokens produced by the native mobile SDKs-
Other apps (e.g websites, apps on facebook.com) need to use the login flows documented elsewhere in the documentation and require the user to be logged into Facebook in their browser

How to retrieve posts of user after he logged out from FB

I'm trying to figure out a core concept in FB that even after reading a lot of FB documentation, couldn't understand.
Let's say I'm building an app (that will reside in a tab), in which I want to see the last post of a user. I want to do this approximately one month after the user approved my app, without him using the app again.
I assume I will need to use a long-lived expiration token that will be saved to my DB.
A month after I will run a procedure that will use this token and check the user posts.
Is this correct?
What about a situation in which the user logged out? The token is no longer valid.. does this mean I will never be able to access user posts unless he will access my app?
Isn't this a bit weird (since he already approved my app)?
Not necessarily.
Firstly, you need the read_stream permission from the user when they authenticate your app. Then, because you are intending to use Facebook as the app, rather than as the user, you need to authenticate as an app, which is a simple process:
In order to get an access token for the app, all you need to do is use the following URL:
https://graph.facebook.com/oauth/access_token?client_id=YOUR_APP_ID&client_secret=YOUR_APP_SECRET&grant_type=client_credentials
Because these tokens are time-limited, it may be easier to request a token each time you use the Graph API, rather than storing it in a database and waiting for it to expire.
Then, all you need to do is use the following request:
https://graph.facebook.com/USER_ID/feed?access_token=YOUR_ACCESS_TOKEN
The upside to this is that it does not matter whether or not the user is logged into Facebook.
See here for more details:
https://developers.facebook.com/docs/authentication/applications/

Long-lasting FB access-token for server to pull FB page info

I'm aware that there are many questions about Facebook access-tokens and the grief they cause, but despite much experimentation and reading many frustratingly vague blog articles (FB and otherwise), I'm still struggling to get a clear answer to my needs. Let me succinctly break down my process so far:
I am creating a site that, server-side, needs to pull the posts/statuses from a single Facebook Page
I am an admin of that Facebook Page
I have created a Facebook App
Using the Facebook Graph API Explorer, I've generated a short-lived key, connected to my app and my account, that grants permission to my account to view the access-tokens for my pages
I've converted my short-lived key to a long-lived key (60 days) ala scenario 4 from this
And here's where I am stuck. My 60 day key works fine for my server to pull the info needed from the page, but as far I can tell, there's no way to programmatically extend that 60 day key. I also do not know of a way to generate a new short-lived key without manually going to the Facebook Graph API Explorer and creating one.
Since it is my server making the requests to the Facebook API and not a user-based system (where I could easily request that a user authorize the Facebook app again), this creates a very clunky system. Since Facebook deprecated offline_access, is there really no permanent way to have my server pull info from my own page? Will I really have to create a new key by hand and manually update my server with it every 60 days?
Or is there something I'm missing?
Update:
The step-by-step guide that was previously found here has been migrated down into its own answer.
These are the steps that were previously in the question - they have been migrated to this answer.
Having found that it is possible to generate a Facebook Page Access Token that does not expire (with help from #Igy), here is a clear, step-by-step quide for all those looking to the same:
Make sure you are the admin of the FB page you wish to pull info from
Create a FB App (should be with the same user account that is the page admin)
Head over to the Facebook Graph API Explorer
On the top right, select the FB App you created from the "Application" drop down list
Click "Get Access Token"
Make sure you add the manage_pages permission
Convert this short-lived access token into a long-lived one by making this Graph API call:
https://graph.facebook.com/oauth/access_token?client_id=<your FB App ID >&client_secret=<your FB App secret>&grant_type=fb_exchange_token&fb_exchange_token=<your short-lived access token>
Grab the new long-lived access token returned back
Make a Graph API call to see your accounts using the new long-lived access token: https://graph.facebook.com/me/accounts?access_token=<your long-lived access token>
Grab the access_token for the page you'll be pulling info from
Lint the token to see that it is set to Expires: Never!
That should do it. You should now have a Facebook Page Access Token that doesn't expire, unless:
You change your Facebook account password
You lose admin access for the target page
You delete or de-authorize your Facebook App
Any of these will cause the access token to become invalid.
If you are getting (#100) Tried accessing nonexisting field (accounts) on node type (Page), go to the Access Token Debugger, copy the value of User ID, and use it to replace the "me" part of the URL in step 9.
This is covered in the Offline Access deprecation document
Use the 60-day token for the page admin to retrieve a Page Access Token (via /PAGE_ID?fields=access_token or /me/accounts) - the Page access token will not have an expiry time
An approach that works in 2019
I was recently trying to achieve something similar (to the use case described in this thread), but I wanted to make sure to respect Facebook's current policies, so I did a little research and here I'm sharing what I found.
My use case
So, as I said already, my use case is very similar to the one described here; that is:
I'm doing some work for a school district.
They are using a software tool to manage pretty much everything that relates to school transportation.
That tool allows them to send email notifications (to subscribers) when they publish bus delay alerts and school closure alerts.
A lot of people in the community follow the organization on their Facebook page, and that's the only place they look for those alerts.
So an employee of the organization has to manually publish each notification on the Facebook page (in addition to creating it in the transportation software). Moreover, those notifications eventually expire (or are simply deleted before they expire), so the employee has to go back later on to delete them manually as well.
It's a waist of time, so what we are trying to do here is to develop as simple system that periodically polls the software tool's database for new (and expired) notifications and update them (i.e. add and remove) on the Facebook page.
This is, in my view, a legitimate use case, but I wasn't sure how to implement it in a way that's in line with Facebook's policies.
The accepted answer
I followed the steps of the accepted answer and it worked, except that things appear to have changed: now, even though the generated page token does not expire, access to data does expire after around 60 days. You will see that as well if you follow the procedure and inspect the page token in the FB Token Debugger Tool.
Besides, the fact that the generated page tokens are tied to the user account is also unfortunate, because if the user updates his/her password, then the page token also gets invalidated.
How to do it in 2019
After several hours of research, I stumbled upon the following Facebook documentation article: Business Login for Direct Businesses.
It turns out that it is now possible, following the steps described in the above article, to generate a page token that is not associated to any particular Facebook user account and which will not expire (unless the FB App gets deleted or the underlying application token gets deleted, you know...)
So here are the steps and the most important parts:
You need a Business Manager account.
Verification will be required and a digital contract will have to be signed.
You need to add the target Facebook page to that account.
You need to create a Facebook App, and transfer that app to the same Business Manager account as well.
The app will have to go through Facebook's review process, because the following permissions will be needed: manage_pages and publish_pages.
Important note For the posts made using the generate page token to be visible to users other than the application administrators, that app will need to have been published and approved.
You may still experiment with the concept without submitting for review, but the posts won't be publicly visible.
In the Business Manager account (only after your app and page have been added to the account), you need to create what's called a System User, and give that user admin role (or permissions) to the target Facebook page.
A system user is owned by the Business Manager account, and isn't tied to a specific user. My current understanding is that one major use case for a system user is programmatic access to Facebook's Graph API (just what we need).
Then, for that system user, you need to generate a access token (which will be never-expiring). You will be prompted to select for which app. You will then select your target app.
You will then need to use the generated app token to generate a page token, which will also be never-expiring. The procedure is described in this article as:
GET /<PAGE_ID>?fields=access_token&access_token=<SYSTEM_USER_ACCESS_TOKEN>
That's it.
That token will never expire, and it won't be tied to a particular Facebook user, so it's exactly what we need!
The last part is to make sure that your Facebook app gets approved by Facebook. It's in fact the most important part, because the whole procedure is worthless if people don't see our posts.
I wanted to know for sure that I could rely on the above procedure to build something for my client without Facebook rejecting it in the end, so, beforehand (i.e. before starting to work on my client's project), I went through the whole process of creating a page, an app, a Business Manager account, etc. I verified my business. I submitted my app for review. In my request, I was very specific about my use case and emphasized that the app was for "self-use" (i.e. that the organization is developing an app for itself, not for other Facebook users). I got approved without less than 24 hours.
A few other notes about the app review process:
I had to select a platform for the app, so I selected website.
I had to indicate why the app needed the two permissions and how it was going to use them.
I had to indicate why the reviewer would not be able to sign into my app and try it (i.e. because the app will be used by a worker process).
For the mandatory screencasts, I simply presented manual operations in the terminal using the curl utility (to generate the page token and make posts to the Facebook page). I also showed how I was using Business Manager to link the system user to the page and generate a token, and so on.
Again, I was very specific about my use case, and I think that that helped.
I hope this information will be useful to people with similar use cases.
Many thanks to #redhotvengeance for step-by-step guide.
After some time, now there is clearly described in Facebook documentation:
https://developers.facebook.com/docs/facebook-login/access-tokens/expiration-and-extension
Extending Page Access Tokens
Apps can retrieve a page access token from Page admin users when they
authenticate with the manage_pages permission. If the user access
token used to retrieve this page access token is short-lived, the page
access token will also be short-lived.
To get a longer-lived page access token, exchange the User access
token for a long-lived one, as above, and then request the Page access
token. The resulting page access token will not have any expiry time.
You can also copy and past from the app dashboard on facebook.
The steps:
Go to https://developers.facebook.com
Select your app in the top right corner of the page
(pic of what it looks like)
Click on Messenger from the options on the left (it will go to setting automatically) (pic of what it looks like)
Go to the "Token Generation" section in the page. Select what page you want to generate the token for. (pic of what that section looks like)
The copy and past your page token where ever you need it.
Keep in mind that while in theory your token won't expire, that it is directly tied to what ever facebook account your logged into. So say you change your password or you remove the permissions from between your account and your app then your token won't be valid any more.