We're hoping to create mobile phone applications for (among other features) posting video to a user's FaceBook page. However, using their API, it looks like we would need to open a web viewer and have the user enter their login credentials every time the application is used. We would prefer to store these credentials so the user only has to login once.
We could of course save the http login post and resend it as needed, but this breaks if FaceBook changes their API and I worry about their terms of service and using an unofficial hack such as this.
Maybe someone knows of another application that uses Facebook this way?
You should have been returned an oAuth token to use.
The new Facebook API has a service you can call with the old tokens and it returns you a new oAuth token.
You just have to add offline_access to your permissions. You do this by adding &scope=offline_permissions at the end of your authorization url. Then your oAuth token won't expire.
Related
We have a website where the only way to login and authenticate yourself with the site is with Facebook (this was not my choice). The first time you login with Facebook, an account gets automatically created for you.
We now want to create an iPhone application for our site and also a public API for others to use our service.
This question is about how to authenticate with our website from the app/API and is broken into 2 parts:
What is the correct way to handle REST authentication from an API to a website which only uses Facebook OAuth as an authentication method?
I have read and researched a lot about standard methods of authentication for REST API. We can't use such methods as Basic Auth over HTTPS, as there are no credentials for a user as such. Something like this seems to be only for authenticating applications using the API.
Currently, the best way I can think is you hit an /authorize end-point on our API, it redirects to Facebook OAuth, then redirects back to the site and provides a 'token' which the user of the API can use to authenticate subsequent requests.
For an official application that we create, we wouldn't necessarily need to use the public API in the same way. What would be the best way then to talk to our website and authenticate users?
I understand (I think) how to authenticate 3rd-party applications that are using our API, using API (public) keys and secret (private) keys. However, when it comes to authenticating the user who is using the app, I am getting rather confused about how to go about it when the only way we have to authenticate a user is Facebook.
I feel like I'm missing something very obvious, or don't fully understand how public REST APIs should work, so any advice and help would be greatly appreciated.
UPDATE: see below
I've been thinking hard about this question too. It's not entirely clear to me yet but here's the route I am thinking of going. I am creating a REST API an my users only auth with Facebook connect.
On the CLIENT:
Use the Facebook API to login and get an OAUTH2 code.
Exchange this code for an access token.
In every call to my custom API I'll include the Facebook user id and the access token.
On the API (for every method that requires user authentication):
Make a request to the /me Facebook graph using the access token from above.
Verify that the Facebook user id returned matches the user id passed to my API from above.
If the access token has expired additional communication is required.
I have yet to test this. How does it sound?
--- Update: July 27th, 2014 to answer question ---
I only use the above exchange once upon login. Once I determine which user is logging in, I create my own access token, and that token is used from that point going forward. So the new flow looks like this...
On the CLIENT:
Use the Facebook API to login and get an OAUTH2 code.
Exchange this code for an access token.
Request an access token from my API, including the Facebook token as a parameter
On the API
Receive access token request.
Make a request to the /me Facebook graph using the facebook access token
Verify that the Facebook user exists and match to a user in my database
Create my own access token, save it and return it to the client to be used from this point forward
This is my implementation using JWTs (JSON Web Tokens), basically similar to Chris' updated answer. I have used Facebook JS SDK and JWT.
Here's my implementation.
Client: Use Facebook JS SDK to log in and get the access token.
Client: Request JWT from my API by calling /verify-access-token endpoint.
MyAPI: Receives access token, verify it by calling /me endpoint of Facebook API.
MyAPI: If access token is valid, finds the user from database, logs in the user if exist. Create a JWT with required fields as payload, set an expiry, sign with the secret key and send back to the client.
Client: Stores the JWT in local storage.
Client: Sends the token (the JWT from step 5) along with the request for the next API call.
MyAPI: validate the token with the secret key, if token is valid, exchange the token for a new one, send it back to the client along with the API response. (No external API calls for verification of the token here after) [if the token is invalid/expired request client to authenticate again and repeat from 1]
Client Replaces the stored token with the new one and use it for the next API call. Once the token expiry is met, the token expires revoking access to API.
Every token is used once.
Read more answers about security and JWT
How secure is JWT
If you can decode JWT how are they secure?
JSON Web Tokens (JWT) as user identification and authentication tokens
I am trying to answer the same question and have been going through a lot of reading recently...
I won't have "the" answer but things are getting a little clearer for me. Have you read the comments in the article you mentioned? I found them really interesting and helpful.
As a result, and in the light of how things have evolved since the first article has been written, here's what I think I'll do:
HTTPS everywhere — this allows you to forget about HMAC, signing, nonce, ...
Use OAuth2:
When authentication requests come from my own apps/website, use this 'trick' (or a variation of it) described in a reply to the article mentioned before.
In my case, I have two types of users: those with classic login/password credentials and those who have signed up with Facebook Connect.
So I'd provide a regular login form with a "Login with Facebook" button. If the user logs in with his "classic" credentials, I'd just send these to my OAuth2 endpoint with a grant_type=password.
If he chooses to log in via Facebook, I think that would be a two-steps process:
First, use Facebook iOS SDK to open an FBSession
When that's done and the app is given back control, there should be a way to get a Facebook ID for that user. I'd send this ID alone to my OAuth2 endpoint with an extension grant understood by my server as "using an FB User ID".
Please note that I am still heavily researching on all this stuff, so that might not be a perfect answer... maybe not even a correct one! But I think that would make for a good starting point.
The idea of using an "extension grant" for the Facebook authentication might involve having to register it to do things properly? I'm not quite sure.
Anyway, I hope I was able to help you even a bit, and that at least it can start a discussion to find the best solution to this problem :)
Update
The Facebook login is not a solution as pointed in the comments: anybody could send an arbitrary user ID and log in as this user on the API.
What about doing it like this:
Show a login form with a "Facebook login" button
If this login method is chosen, act kinda like the Facebook SDK: open a web page from your authentication server, which will initiate the Facebook login.
Once the user has logged in, Facebook will use your redirect URL to confirm; make that URL point to another endpoint of your authentication server (possibly with an extra parameter indicating the call came from an app?)
When the authentication endpoint is hit, the authentication can securely identify the user, retain its FB User ID/FB Session and return an access token to your app using a custom URL scheme, just like the Facebook SDK would do
Looks better?
I need to post message on a certain FB page as a owner by cron, using php and ZF 1.1.X. For this small issue, I don't want to create a full OAuth stack. Is it possible to communicate with FB API (it's desirable, PHP SDK for FB) without it, such as twitter with his precreated access tokens (Access token, Access token secret)?
As long as you need an active user access_token to retrieve desired data this is not possible to skip OAuth flow.
Without authenticating user you only have application access_token (in old format APP_ID|APP_SECRET, but it's still works) and only limited access to most of Graph API endpoints and Application settings.
Actually there is nothing hard in implementing the user authentication with OAuth flow and it is completely transparent with usage of PHP-SDK.
Just look at the sample code in documentation for server-side authentication
Yes, you need to build an app and then authorize the page via the app while requesting the manage_page permission.
You should make yourself familiar with the Server Side Auth process as well.
I am bit stuck with facebook authentication in my wp7 app.
What I have right now:
login page with WebBrowser control
I can get access_token from facebook
Save it to phone IsolatedStorage
What I want to do is to skip login page if the user is already authenticated, but I don't really understand the flow, what condition should I check.
On server side I have REST api, when user is authenticated I get his personal information from facebook and call my api to store this information in the database + access_token. Then I used it with all requests to secure my api. Is it good approach?
You don't really check a condition. You try to do whatever it is you want to do with the access token (post status, upload picture, or whatever) and then, if you get an oauth exception, you go and bring up the browser again to get a new access token (browser will just flash - it won't require any user input unless they actually changed their password or something)
I am using the Graph API for Facebook on my iPhone application. The problem is, I don't want the user to have to re enter their email address each time they want to login to integrate Facebook with my app. Is there a way to save and auto fill the login information using the Graph API?
Using the Graph API, there is no need for you to store the credentials, more than that, you should NOT store the credentials. As explained in the API dedicated help page the authentication process is handled by a secure token.
Meaning that if the user is already authenticated on Facebook using another application, it might be ( based on authentication process used ) already authenticated within your app.
You might check the token validity by using the isSessionValid method from the Facebook class.
Have a look to the iOS Facebook SSO link, it explains everything you need.
I want to allow users connect to my website using their facebook account.
First, the user authorizes my application and then I get an access token. Problem is, that I'm supposed on the first time to register the user, and the next time to auto login him based on his facebook email.
How do I create a SECURE way to auto login the user?
I'm using pure javascript, but I can't find any way to create a secure mechanism.
Thanks.
Facebook should handle all that for you - when they come back to your website, they can click the 'login' button(javascript SDK) and facebook should pass you back an access token.
I may, however, have misunderstood the question.