Ember Torii facebook authentication not able to get user email - facebook

I am using Ember CLI + ember simple auth torii link
to get authentication code from facebook for my ember app.
This is my environment.js file
ENV['torii'] = {
providers: {
'facebook-oauth2': {
apiKey: '865549306850377',
scope: 'email',
//redirectUri: window.document.location.href
redirectUri: 'http://localhost:4200/'
}
}
};
And my login controller looks like this -
facebook: function() {
var _this = this;
this.get('session').authenticate('simple-auth-authenticator:torii', 'facebook-oauth2').then(function(data){
console.log("status - ", _this.get('session'));
});
}
And login.hbs -
<li><button {{action "facebook" "facebook-oauth2"}}>Facebook OAuth2</button></li>
After the user clicks on the link, a facebook popup opens and ember app gets a token.
How do I get the user's email id along with this token ?
Has anybody faced a similar issue ?

So you're using oauth2, so all you're ever going to get is an authorization token. With this token, you can then go off and request other information. The token is basically just there to speed up the validation of users against your application.
If you want to get user information, you would need to create another method (probably on your server-side), which swaps the authorization code for an access token: like so (or alternatively you can request an access token directly, which would remove the need for a server-side solution.
Using the access Token you can then request the Facebook User ID, using the debug token endpoint, and after that you will be able get to any endpoint to get the information you need.

Related

Update Facebook Open Graph with app access token instead of user access token

I'm trying to force facebook to update the OG information automatically using javascript (i.e. what you can manually do on this page), using an app access token.
I've been able to make it work using a user access token and the api with the following code:
FB.api("/", "post", {
accessToken,
id: url,
scrape: true
}, function(response) {
console.log("Response", response)
}
);
However when I try to use the app access token I get the error
"message":"An access token is required to request this resource.",
"type":"OAuthException",
"code":104"
I've tried obtaining the access token both using a GET request:
GET /oauth/access_token
?client_id={app-id}
&client_secret={app-secret}
&grant_type=client_credentials
and by concatenating the add id and secret.
The result is the same when using curl instead of the Javascript api.
It seems to me it can't be intended that you can force an OG scrape as a user but not with an app token; it doesn't sound like a user oriented action.
Any ideas?

Can I post reviews on Facebook through an API?

Is it possible to post user reviews to a FB page via an API?
I want to have an app on a phone that will let users review my business when they walk in to my store.
Edit:- This is what I've tried so far.
I used the passport module in Nodejs for authentication and was able to retrieve the access token from FB, including manage_pages, publish_pages and read_insights.
app.get('/auth/facebook', passport.authenticate('facebook', { scope : ['email', 'manage_pages','publish_pages','read_insights' ]}));
My passport strategy has this
clientID : configAuth.facebookAuth.clientID, //my app's client id
clientSecret : configAuth.facebookAuth.clientSecret, //my app's client secret
callbackURL : configAuth.facebookAuth.callbackURL, //the callback URL after authentication
profileFields: ["emails", "displayName"]
I am able to post as the page using the NPM FBGraph module.
var graph = require('fbgraph');
graph.setAccessToken(req.user.facebook.token);
graph.post("{My page's ID}/feed", "Message test", function(err, res) {
console.log(res); // { id: xxxxx}
});
This lets me post the "Message test" to my page's feed.
I am not able to find a reference to post reviews for the page through the Graph API though and was wondering if that is possible.
https://developers.facebook.com/docs/graph-api/reference/page/ratings#Creating
You can't perform this operation on this endpoint.
Meaning, it´s not possible. Not sure what you would do with publish_pages though, because ratings/reviews are made by users, not by pages...If it would be possible, then only with publish_actions.

Doubts about Security in Login for Web with Facebook Oauth JavaScript SDK that send ACCESS TOKEN to server

I have doubts about security of my process of authentication oauth with facebook..
I use login for web with javascript sdk with fb button:
I get an Access Token successfully and pass it to server(calling check_facebook_session.php) to make API call to Facebook Provider..
In the following code there is also the log in console of access token.
Everything works!!! on the server I use the php sdk to call the API REST with APPID, APPSECRET and ACCESS_TOKEN:
**
Now my question, have I a security problem?
Is a bad idea to pass the token to the server?
The token that is visible on the client can be used WITHOUT APP SECRET to get information about the user logged?
**
Note: Google+ Sign-In for server-side apps Implementing the one-time-code flow with step:
- Include the Google+ script on your page.
- Add the sign-in button to your page.
- Sign in the user.
- Send the authorization code to the server.
as explained in: https://developers.google.com/+/web/signin/server-side-flow
Unlike facebook google in the js client return a CODE, not an ACCES TOKEN and the server receive and use it to request ACCESS TOKEN.
Thanks..
Following is the javascript code for facebook:
window.fbAsyncInit = function() {
FB.init({
appId : FACEBOOK_APP_ID, // App ID
status : true, // check login status
cookie : false, // enable/disable cookies to allow the server to access the session
xfbml : true // parse XFBML
});
FB.Event.subscribe('auth.authResponseChange', function(response)
{
if (response.status === 'connected')
{
var accessToken = FB.getAuthResponse()['accessToken'];
console.log(accessToken);
$.ajax({
type: 'POST',
url: check_facebook_session.php,
contentType: 'application/x-www-form-urlencoded; charset=utf-8',
processData: false,
data: 'token=' + accessToken,
success: function(result)
{
if(result == 'SUCCESS'){window.location.href = fb_callback_url}
},
error: function(xhr)
{
alert('Request Status: ' + xhr.status + ' Status Text: ' + xhr.statusText + ' ' + xhr.responseText);
}
});
}
else if (response.status === 'not_authorized')
{
FB.login();
}
else
{
FB.login();
}
});
};
// Load the SDK asynchronously
.......
}(document));
I did some testing and came to the conclusions that I hope can be useful.
In Facebook SDK for JavaScript it automatically handles access token storage and tracking of login status, so apps using it do not need to create their own mechanisms for doing so, and can proceed to making API calls.
The system seems safe because I believe that the callback url of the call is the site that host the page and configured between those of the facebook application, so I can change the application id in the javascript code but the sdk response with error message and get the user's token pretending to be another application. This was already obvious to those who know the flow :-)
Passes the token to the server is definitely a bad idea because it can be snorted and used by simply calling https://graph.facebook.com/me?access_token=... to get user information, In the different flow of google the token is not passed but is passed the code necessary to obtain it.
The best solution to use advantage of client and server is it:
Used in conjunction with the Facebook SDK for JavaScript,
the PHP SDK can share user sessions seamlessly across the client and server.
If people are logged in with Facebook and have authorized your app,
the JavaScript SDK can pick up the user session and persist this in a cookie,
which the PHP SDK reads without any intervention on the developer's part.
To enable this functionality, ensure that when you embed and initialize the JS SDK,
you set both the status and the cookie parameters of the object passed to FB.init() to true.
Regards..
i think it is secure because the user's data is only returned with connected status after user authentication with facebook.
https://developers.facebook.com/docs/reference/javascript/FB.getLoginStatus/
I have followed Facebook example on getting access token by using $fb->getJavaScriptHelper();
https://developers.facebook.com/docs/php/howto/example_access_token_from_javascript
$helper = $fb->getJavaScriptHelper();
$accessToken = $helper->getAccessToken();
echo $accessToken->getValue();
P.S. Add try{} catch() {} blocks, as in Facebook example for error handling.

Facebook: Permanent Page Access Token?

I work on a project that has Facebook pages as one of its data sources. It imports some data from it periodically with no GUI involved. Then we use a web app to show the data we already have.
Not all the information is public. This means I have to get access to the data once and then keep it. However, I don't know the process and I haven't found a good tutorial on that yet. I guess I need an access_token, how can I get it from the user, step by step? The user is an admin of a facebook page, will he have to add some FB app of ours to the page?
EDIT: Thanks #phwd for the tip. I made a tutorial how to get a permanent page access token, even with offline_access no longer existing.
EDIT: I just found out it's answered here: Long-lasting FB access-token for server to pull FB page info
Following the instructions laid out in Facebook's extending page tokens documentation I was able to get a page access token that does not expire.
I suggest using the Graph API Explorer for all of these steps except where otherwise stated.
0. Create Facebook App
If you already have an app, skip to step 1.
Go to My Apps.
Click "+ Add a New App".
Setup a website app.
You don't need to change its permissions or anything. You just need an app that wont go away before you're done with your access token.
1. Get User Short-Lived Access Token
Go to the Graph API Explorer.
Select the application you want to get the access token for (in the "Application" drop-down menu, not the "My Apps" menu).
Click "Get Token" > "Get User Access Token".
In the pop-up, under the "Extended Permissions" tab, check "manage_pages".
Click "Get Access Token".
Grant access from a Facebook account that has access to manage the target page. Note that if this user loses access the final, never-expiring access token will likely stop working.
The token that appears in the "Access Token" field is your short-lived access token.
2. Generate Long-Lived Access Token
Following these instructions from the Facebook docs, make a GET request to
https://graph.facebook.com/v2.10/oauth/access_token?grant_type=fb_exchange_token&client_id={app_id}&client_secret={app_secret}&fb_exchange_token={short_lived_token}
entering in your app's ID and secret and the short-lived token generated in the previous step.
You cannot use the Graph API Explorer. For some reason it gets stuck on this request. I think it's because the response isn't JSON, but a query string. Since it's a GET request, you can just go to the URL in your browser.
The response should look like this:
{"access_token":"ABC123","token_type":"bearer","expires_in":5183791}
"ABC123" will be your long-lived access token. You can put it into the Access Token Debugger to verify. Under "Expires" it should have something like "2 months".
3. Get User ID
Using the long-lived access token, make a GET request to
https://graph.facebook.com/v2.10/me?access_token={long_lived_access_token}
The id field is your account ID. You'll need it for the next step.
4. Get Permanent Page Access Token
Make a GET request to
https://graph.facebook.com/v2.10/{account_id}/accounts?access_token={long_lived_access_token}
The JSON response should have a data field under which is an array of items the user has access to. Find the item for the page you want the permanent access token from. The access_token field should have your permanent access token. Copy it and test it in the Access Token Debugger. Under "Expires" it should say "Never".
Here's my solution using only Graph API Explorer & Access Token Debugger:
Graph API Explorer:
Select your App from the top right dropdown menu
Select "Get User Access Token" from dropdown (right of access token field) and select needed permissions
Copy user access token
Access Token Debugger:
Paste copied token and press "Debug"
Press "Extend Access Token" and copy the generated long-lived user access token
Graph API Explorer:
Paste copied token into the "Access Token" field
Make a GET request with "PAGE_ID?fields=access_token"
Find the permanent page access token in the response (node "access_token")
(Optional) Access Token Debugger:
Paste the permanent token and press "Debug"
"Expires" should be "Never"
(Tested with API Version 2.9-2.11, 3.0-3.1)
In addition to the recommended steps in the Vlasec answer, you can use:
Graph API explorer to make the queries, e.g. /{pageId}?fields=access_token&access_token=THE_ACCESS_TOKEN_PROVIDED_BY_GRAPH_EXPLORER
Access Token Debugger to get information about the access token.
Another PHP answer to make lives easier. Updated for Facebook Graph API 2.9 . Just fill 'er up and load.
<?php
$args=[
/*-- Permanent access token generator for Facebook Graph API version 2.9 --*/
//Instructions: Fill Input Area below and then run this php file
/*-- INPUT AREA START --*/
'usertoken'=>'',
'appid'=>'',
'appsecret'=>'',
'pageid'=>''
/*-- INPUT AREA END --*/
];
echo 'Permanent access token is: <input type="text" value="'.generate_token($args).'"></input>';
function generate_token($args){
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.9/oauth/access_token?grant_type=fb_exchange_token&client_id={$args['appid']}&client_secret={$args['appsecret']}&fb_exchange_token={$args['usertoken']}")); // get long-lived token
$longtoken=$r->access_token;
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.9/me?access_token={$longtoken}")); // get user id
$userid=$r->id;
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.9/{$userid}?fields=access_token&access_token={$longtoken}")); // get permanent token
if($r->id==$args['pageid']) $finaltoken=$r->access_token;
return $finaltoken;
}
?>
Addendum: (alternative)
Graph 2.9 onwards , you can skip much of the hassle of getting a long access token by simply clicking Extend Access Token at the bottom of the Access Token Debugger tool, after having debugged a short access token. Armed with information about pageid and longlivedtoken, run the php below to get permanent access token.
<?php
$args=[
/*-- Permanent access token generator for Facebook Graph API version 2.9 --*/
//Instructions: Fill Input Area below and then run this php file
/*-- INPUT AREA START --*/
'longlivedtoken'=>'',
'pageid'=>''
/*-- INPUT AREA END --*/
];
echo 'Permanent access token is: <input type="text" value="'.generate_token($args).'"></input>';
function generate_token($args){
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.9/{$args['pageid']}?fields=access_token&access_token={$args['longlivedtoken']}"));
return $r->access_token;
}
?>
Although the second code saves you a lot of hassle, I recommend running the first php code unless you are in a lot of hurry because it cross-checks pageid and userid. The second code will not end up working if you choose user token by mistake.
Thanks to dw1 and Rob
I made a PHP script to make it easier. Create an app. In the Graph API Explorer select your App and get a user token with manage_pages and publish_pages permission. Find your page's ID at the bottom of its About page. Fill in the config vars and run the script.
<?php
$args=[
'usertoken'=>'',
'appid'=>'',
'appsecret'=>'',
'pageid'=>''
];
echo generate_token($args);
function generate_token($args){
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.8/oauth/access_token?grant_type=fb_exchange_token&client_id={$args['appid']}&client_secret={$args['appsecret']}&fb_exchange_token={$args['usertoken']}")); // get long-lived token
$longtoken=$r->access_token;
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.8/me?access_token={$longtoken}")); // get user id
$userid=$r->id;
$r=json_decode(file_get_contents("https://graph.facebook.com/v2.8/{$userid}/accounts?access_token={$longtoken}")); // get permanent token
foreach($r->data as $d) if($d->id==$args['pageid']) return $d->access_token;
}
I tried these steps:
https://developers.facebook.com/docs/marketing-api/access#graph-api-explorer
Get Permanent Page Access Token
Go to Graph API Explorer
Select your app in Application
Paste the long-lived access token into Access Token
Next to Access Token, choose the page you want an access token for. The access token appears as a new string.
Click i to see the properties of this access token
Click “Open in Access Token Tool” button again to open the “Access Token Debugger” tool to check the properties
One Tip, it only worked for me when the page language is english.
As all the earlier answers are old, and due to ever changing policies from facebook other mentioned answers might not work for permanent tokens.
After lot of debugging ,I am able to get the never expires token using following steps:
Graph API Explorer:
Open graph api explorer and select the page for which you want to obtain the access token in the right-hand drop-down box, click on the Send button and copy the resulting access_token, which will be a short-lived token
Copy that token and paste it in access token debugger and press debug button, in the bottom of the page click on extend token link, which will extend your token expiry to two months.
Copy that extended token and paste it in the below url with your pageId, and hit in the browser url
https://graph.facebook.com/{page_id}?fields=access_token&access_token={long_lived_token}
U can check that token in access token debugger tool and verify Expires field , which will show never.
Thats it
Most of the answers above now doesn't give permanent token, they only extend it to 2 months. Here's how I got it:
From Graph Explorer tool, select the relevant permissions and get the short lived page access token.
Go to debugger tool and paste your access token. Then, click on 'Extend Token' button at the bottom of the page.
Copy the the extended token and use it in this API:
https://graph.facebook.com/v2.10/me?fields=access_token&access_token=<extended_access_token>
This should return you the permanent access token. You can verify it in debugger tool, the expires at field should say 'Never'.
If you are requesting only page data, then you can use a page access token. You will only have to authorize the user once to get the user access token; extend it to two months validity then request the token for the page. This is all explained in Scenario 5. Note, that the acquired page access token is only valid for as long as the user access token is valid.
While getting the permanent access token I followed above 5 steps as Donut mentioned. However in the 5th step while generating permanent access token its returning the long lived access token(Which is valid for 2 months) not permanent access token(which never expires). what I noticed is the current version of Graph API is V2.5. If you trying to get the permanent access token with V2.5 its giving long lived access token.Try to make API call with V2.2(if you are not able to change version in the graph api explorer,hit the API call https://graph.facebook.com/v2.2/{account_id}/accounts?access_token={long_lived_access_token} in the new tab with V2.2) then you will get the permanent access token(Which never expires)
In addition to mentioned methods it is worth mentioning that for server-to-server applications, you can also use this form of permanent access token:
app_id|app_secret
This type of access token is called App Token. It can generally be used to call Graph API and query for public nodes within your application back-end.
It is mentioned here: https://developers.facebook.com/docs/facebook-login/access-tokens
If you have facebook's app, then you can try with app-id & app-secret.
Like :
access_token={your-app_id}|{your-app_secret}
it will don't require to change the token frequently.
Thanks to #donut I managed to get the never expiring access token in JavaScript.
// Initialize exchange
fetch('https://graph.facebook.com/v3.2/oauth/access_token?grant_type=fb_exchange_token&client_id={client_id}&client_secret={client_secret}&fb_exchange_token={short_lived_token}')
.then((data) => {
return data.json();
})
.then((json) => {
// Get the user data
fetch(`https://graph.facebook.com/v3.2/me?access_token=${json.access_token}`)
.then((data) => {
return data.json();
})
.then((userData) => {
// Get the page token
fetch(`https://graph.facebook.com/v3.2/${userData.id}/accounts?access_token=${json.access_token}`)
.then((data) => {
return data.json();
})
.then((pageToken) => {
// Save the access token somewhere
// You'll need it at later point
})
.catch((err) => console.error(err))
})
.catch((err) => console.error(err))
})
.catch((err) => {
console.error(err);
})
and then I used the saved access token like this
fetch('https://graph.facebook.com/v3.2/{page_id}?fields=fan_count&access_token={token_from_the_data_array}')
.then((data) => {
return data.json();
})
.then((json) => {
// Do stuff
})
.catch((err) => console.error(err))
I hope that someone can trim this code because it's kinda messy but it was the only way I could think of.
Application request limit reached (#4) - FB API v2.1 and greater
This answer led me to the "ultimate answer for us" and so it is very much related so I am appending it here. While it's related to the above it is different and it seems FB has simplified the process some.
Our sharing counts on our site stopped worked when FB rolled over the api to v 2.1. In our case we already had a FB APP and we were NOT using the FB login. So what we needed to do was get a FB APP Token to make the new requests. This is as of Aug. 23 2016.
Go to: https://developers.facebook.com/tools/explorer
Select the api version and then use GET and paste the following:
/oauth/access_token?client_id={app-id}&client_secret={app-secret}&grant_type=client_credentials
You will want to go grab your app id and your app secret from your app page. Main FB Apps developer page
Run the graph query and you will see:
{
"access_token": "app-id|app-token",
"token_type": "bearer"
}
Where "app-id" and "app-token" will be your app id from your FB app page and the generated FB App HASH you just received.
Next go test your new APP access token: FB Access Token tester
You should see, by pasting the "app-token" into the token tester, a single app based token without an expiration date/time.
In our case we are using the FB js sdk so we changed our call to be like so (please note this ONLY gets the share count and not the share and comment count combined like it used to be):
FB.api(
'/','GET',{
// this is our FB app token for our FB app
access_token: FBAppToken,
"id":"{$shareUrl}","fields":"id,og_object{ engagement }"
}
This is now working properly. This took a lot of searching and an official bug report with FB to confirm that we have to start making tokenized requests to the FB api. As an aside I did request that they (FB) add a clue to the Error code (#4) that mentions the tokenized request.
I just got another report from one of our devs that our FB comment count is broken as well due to the new need for tokenized requests so I will update this accordingly.
Many of these examples do not work, not sure if it's because of 2.9v coming out but I was banging my head. Anyways I took #dw1 version and modified it a little with the help of #KFunk video and got this working for me for 2.9. Hope this helps.
$args=[
/*-- Permanent access token generator for Facebook Graph API version 2.9 --*/
//Instructions: Fill Input Area below and then run this php file
/*-- INPUT AREA START --*/
'usertoken'=>'',
'appid'=>'',
'appsecret'=>'',
'pageid'=>''
/*-- INPUT AREA END --*/
];
echo 'Permanent access token is: <input type="text" value="'.generate_token($args).'"></input>';
function generate_token($args){
$r = json_decode(file_get_contents("https://graph.facebook.com/v2.9/oauth/access_token?grant_type=fb_exchange_token&client_id={$args['appid']}&client_secret={$args['appsecret']}&fb_exchange_token={$args['usertoken']}")); // get long-lived token
$longtoken=$r->access_token;
$r=json_decode(file_get_contents("https://graph.facebook.com/{$args['pageid']}?fields=access_token&access_token={$longtoken}")); // get user id
$finaltoken=$r->access_token;
return $finaltoken;
}
As of April 2020, my previously-permanent page tokens started expiring sometime between 1 and 12 hours. I started using user tokens with the manage_pages permission to achieve the previous goal (polling a Page's Events). Those tokens appear to be permanent.
I created a python script based on info found in this post, hosted at github.com/k-funk/facebook_permanent_token, to keep track of what params are required, and which methods of obtaining a permanent token are working.
I created a small NodeJS script based on donut's answer. Store the following in a file called get-facebook-access-token.js:
const fetch = require('node-fetch');
const open = require('open');
const api_version = 'v9.0';
const app_id = '';
const app_secret = '';
const short_lived_token = '';
const page_name = '';
const getPermanentAccessToken = async () => {
try {
const long_lived_access_token = await getLongLivedAccessToken();
const account_id = await getAccountId(long_lived_access_token);
const permanent_page_access_token = await getPermanentPageAccessToken(
long_lived_access_token,
account_id
);
checkExpiration(permanent_page_access_token);
} catch (reason) {
console.error(reason);
}
};
const getLongLivedAccessToken = async () => {
const response = await fetch(
`https://graph.facebook.com/${api_version}/oauth/access_token?grant_type=fb_exchange_token&client_id=${app_id}&client_secret=${app_secret}&fb_exchange_token=${short_lived_token}`
);
const body = await response.json();
return body.access_token;
};
const getAccountId = async (long_lived_access_token) => {
const response = await fetch(
`https://graph.facebook.com/${api_version}/me?access_token=${long_lived_access_token}`
);
const body = await response.json();
return body.id;
};
const getPermanentPageAccessToken = async (
long_lived_access_token,
account_id
) => {
const response = await fetch(
`https://graph.facebook.com/${api_version}/${account_id}/accounts?access_token=${long_lived_access_token}`
);
const body = await response.json();
const page_item = body.data.find(item => item.name === page_name);
return page_item.access_token;
};
const checkExpiration = (access_token) => {
open(`https://developers.facebook.com/tools/debug/accesstoken/?access_token=${access_token}&version=${api_version}`);
}
getPermanentAccessToken();
Fill in the constants and then run:
npm install node-fetch
npm install open
node get-facebook-access-token.js
After running the script a page is opened in the browser that shows the token and how long it is valid.
I found this answer which refers to this tool which really helped a lot.
I hope this answer is still valid when you read this.

Facebook access token server-side validation for iPhone app

I'm developing iPhone application, that is based on communication with server, and I want to use Facebook authentication mechanisms.
Basically, I think it should work like this:
In my iPhone app, user logs in to Facebook, using his email and password.
User allows access to his data for related Facebook application.
My iPhone app receives access token, after successful log in.
In further communication with my server, my iPhone application should use the received Facebook access token (for example: in queries).
When my server receives some query from iPhone app, with access token, it should ask Facebook that this token is valid (and for who), and if yes, server should assume that user is authenticated with Facebook.
My question is: how the server should ask Facebook if given access token is valid? I think I should somehow check if the token is valid for my Facebook app.
I've tried many Facebook queries to graph API, that I've found, but nothing worked as I expected. Can you provide me some example?
Here's a two step process you can use to validate that a user access token belongs to your App:
1) Generate an App Access token
(https://developers.facebook.com/docs/howtos/login/login-as-app/)
https://graph.facebook.com/oauth/access_token?
client_id=YOUR_APP_ID
&client_secret=YOUR_APP_SECRET
&grant_type=client_credentials
2) Debug the User Access token
(https://developers.facebook.com/docs/howtos/login/debugging-access-tokens/)
https://graph.facebook.com/debug_token?
input_token=INPUT_TOKEN
&access_token=ACCESS_TOKEN
Where INPUT_TOKEN is the user access token you want to verify, and ACCESS_TOKEN is your app's token that you got from step 1.
The debug endpoint basically dumps all information about a token, so it'll respond with something like this:
{
data: {
app_id: YOUR_APP_ID,
is_valid: true,
metadata: {
sso: "iphone-safari"
},
application: YOUR_APP_NAMESPACE,
user_id: USER_ID,
issued_at: 1366236791,
expires_at: 1371420791,
scopes: [ ]
}
}
If that token isn't from "your app" then it will return an error response.
Update: this answer seems insecure since it doesn't validate the token
first as belonging to your app, see the comments, original answer as
follows:
I assume that you already have the access token in hand. In such a case the simplest way to validate an access token is to issue the following request
https://graph.facebook.com/me?fields=id&access_token=#accesstoken
Here replace #accesstoken with the access token you have. I will breakdown the url and will explain each.
We are issuing a graph api request here which will return the Facebook User Id of the owner of the access token as a JSON string. The keyword 'me' represents the currently logged in user or the owner of the access token. For this request access token is a mandatory parameter.
If the provided access token is not valid or expired Facebook will just return an error message of some sort.
For a valid access token the result will somehow look like this
{
"id": "ID_VALUE"
}
Another solution would be to use https://graph.facebook.com/app/?access_token=[user_access_token] as described by Get application id from user access token (or verify the source application for a token).
This appears to be an undocumented feature, but returns JSON containing the id of the app the token was generated for. If the token wasn't for your app, it returns a 400.
In the latest version of facebook (2.2) you can do it this way:
https://developers.facebook.com/docs/graph-api/reference/v2.2/debug_token
Sample output:
{
"data": {
"app_id": "THE APP ID",
"application": "APP NAME",
"expires_at": 1427245200,
"is_valid": true,
"scopes": [
"public_profile",
"basic_info",
"read_stream",
"email",
"publish_actions",
"read_friendlists",
"user_birthday",
"user_hometown",
"user_location",
"user_likes",
"user_photos",
"user_videos",
"user_friends",
"user_posts"
],
"user_id": "THE USER ID"
}
}
private function facebookRequestMe($access_token)
{
include_once "facebook.php";
$facebook = new Facebook(array(
"appId" => "your_application_id",
"secret" => "your_application_secret"
));
$facebook->setAccessToken($access_token);
return $facebook->api("/me", "GET");
}
You can download the Facebook SDK for PHP from GitHub.
If a user has passed you a Facebook UID that they claim is theirs and you want to check if it's legit, this is a Python function that will verify it against their access token (an implementation of Robin Jome's answer):
def verify_facebook_id(id, access_token):
import requests
import simplejson
params = {'fields': 'id', 'access_token': access_token}
text = requests.get("https://graph.facebook.com/me", params=params).text
json = simplejson.loads(text)
response_id = json["id"]
return response_id == id
This is the only secure method to verify user token using just one request:
https://graph.facebook.com/debug_token?input_token={token-to-inspect}&access_token={app_id}|{app_secret}
Note that a sign "|" in the above URL isn't used as OR but as separator and must be there after fill the other fields.
The response will be JSON looking like that:
{
data: {
app_id: {app_id},
application: {app_name},
expires_at: {some_number},
is_valid: {true|false}
scopes: {array_of_permissions},
user_id: {user_id}
}
}
Reference: https://developers.facebook.com/docs/facebook-login/access-tokens/#apptokens
(above method is mentioned at the bottom of this section)
Along with an access token Facebook also sends an "expires_in" parameter, which is an offset value. Use that to compute for when the access token will expire as an NSDate. Then when you need to do a request compare the current date with the expiration date.
Also try to inspect the status codes and response strings Facebook sends back.