I'm studying how to develop an iOS app and I need to figure out how should I structure it.
Architecture:
I've an external database, a REST api (as interface between the database and the app), and the iOS app.
The question:
I'd like users to authenticate by a simple form or by a Facebook login button but in each case a table 'user' in the database has to be filled with default fields like name, surname, email, profile picture, password(?).
For the standard authentication there are no problem, but for Facebook authentication I'm quite confused about theory:
Should I use access token? How?
When a user get authenticated with Facebook I haven't his password, so how can I get his informations from the database? In the standard way I would give to the database username and password and it would return for example the id field.
Sorry for my english.
You can use the access token of current logged in user
[FBSDKAccessToken currentAccessToken]
and send it to your REST api. From there you can retrieve every information you need and save it to your database (except user's password of course). If a user sign in for first time in your app insert a new user in your database and save user's Facebook User ID.
The whole idea of using authenticate and authorization is not to have access to user's password of another app, but the user authorize (confirm) your app to have access in his/her account with specific permissions.
Here is a step-by-step answer of what you need:
Design for Facebook authentication in an iOS app that also accesses a secured web service
You need to save the currentAccessToken that the login request returns to you.
Then, using Facebook's Graph API, the userID that was returned in the login request, and the user access token, you can request a user object, which has the email address, assuming you added the email permission in the login request.
Also use the Graphi API to retrieve the user's photo using the userID that was returned in the login request:
50x50 pixels
<img src="//graph.facebook.com/{{fid}}/picture">
200 pixels width
<img src="//graph.facebook.com/{{fid}}/picture?type=large">
Related
I am using instagram API in my client's app. This is a kind of a social networking app with profiles for each user. In this app, there is a section which displays instagram recent pictures of a person on their profile page. The issue is that I'm having to log the user in every time they go to view the profile in the instagram section. Can we have it so the user only has to login once and never again?
In other apps like Tinder, we login only once and then our profile is connected to instagram - even if you close the app. This means the app is either storing instagram credentials or the pictures. But latest documentation on instagram developer portal says don't store login credentials or pictures. How can I mimic this behaviour in our app?
For the login purpose, you can retrieve the access token for the particular use which you can store and for the every data retrieval request you can use that access token to get data without making user login again till the access token is valid
to get an access token you can follow the Instagram guide : Instagram: User Authentication
Which is like
Direct the user to our authorization URL. If the user is not logged
in, they will be asked to log in. The user will be asked if they
would like to grant your application access to her Instagram data.
Client Side login
For the images for another user,If you want the public feed of the user you can get directly if you already have the username of the Instagram user by making a get request without need of authentication/access token
https://www.instagram.com/{user-name of Instagram user for which you have to retrieve the media}/media/
Ex: https://www.instagram.com/instagram/media/ , this will return json with the public feed images
I want to give the opportunity for a user of an app to register/login with Facebook or by creating an account. I know that I can get the user's Facebook account email address, and their first and last names. That's basically the only information for creating a 'local' app account, apart from a password. How can I make sure that if that person logs in to Facebook on another device, that their two devices are linked to the same 'local' account? (i.e if they choose to sign in with Facebook with 2 devices, I only want one local account to be created on my server for that user).
Ideally, I want the login schemes for both to be identical. So if that user logs in with Facebook, I can check (securely) that the FB account is linked to a 'local' account, and automatically log that device in without making the user type in a password. Is this possible?
Edit: The 'local' users will be stored in a database on my server, and the front end will be done in Python running alongside the API for the app. Note that 'local' is just referring to the fact that it uses my app web service rather than an external social network.
You can do that within your users database as per below:
assuming you store the user data in a table named userinfo, this table should contain user e-mail, first name, etc..
Add another column in this table named fbemail.
If users signs in using web service, his email will be saved in the email field & the fbemail should be null, if signs in using FB, then both email & fbemail should be the extracted email.
when the user uses FB login, check the fbemail field, if not found, then this is a new user, add his data, if not, then this is a returning user, no need to add his data.
Option 1.
You can identify your Facebook user by his Facebook User ID. If he logs in using Facebook on other device you know it cause he sends you his Facebook User ID in the authentication process. He also sends you Facebook access token which you validate contacting Facebook to see if it is correct. Using this approach you have to have a different authentication scheme for Facebook user and "normal", email user.
Option 2.
To have the same login scheme you can use Facebook to get user email and prepend it in the email text field in your registration screen. The user would need to additionally provide a password. This means that you are not really doing a Login with Facebook, but use Facebook to obtain an email (and any additional information) so the user does not have to type it.
This is an old post but still very valid. You are correct, anybody who has your FB email could potentially access your server rest-api and log into it. To access a backend service you will need to use as password the FB access token generated during the FB log-in. This is stored in the device keychain and can be retrieved as:
NSString *accessToken = [[FBSDKAccessToken currentAccessToken] tokenString];
NSString *userID = [[FBSDKAccessToken currentAccessToken] userID];
The topic of using a FB authentication system in parallel to a custom login/registration system is covered in this FB guide: Using Facebook Login with Existing Login Systems.
In sum, different scenarios need to be addressed:
A person signs up for your app using their email and password, but later they want to use Facebook Login to obtain data from their Facebook account, to post to their timeline, or just to use to log in with in future.
A person signs up for the app using their email and password, but later chooses to log in with Facebook separately. This guide assumes that the email supplied first and the primary email associated with their Facebook account are the same.
A person signs up for the app using Facebook Login and later wants to log in to this account using an email address and password.
The guide recommends using two different tables for the FB log-in and the custom login.
How do I parse a webpage with login and password requirements to view the individual user's information, like facebook for example. I want my app to access to the individual facebook page, after entering login and password in the app.
By now I was able to parse usual webpages with TFHpple, but I have no idea how to pass the login and password requirements to get the page content.
Thank you very much in advance!
Usually the process for logging in is:
User POSTs data to a login form with username and password.
The server responds with a session cookie
Future requests include the session cookie and the server knows that the user is authenticated.
If you wan to do this login process on your user's behalf through our app, you'll need to save the cookies and send them on subsequent requests.
Why don't you use the Facebook iOS SDK:
https://developers.facebook.com/docs/ios/
I think it's a little bit strange from the architecture perspective that you want to parse the personal Facebook newsfeed, when there's the possibility to get the data via the Facebook API (given that you have the appropriate User Permission)...
I've been looking into OAuth for a while, but haven't implemented it in any of my applications yet. I'm having trouble really understanding the full concept, so I still have a few questions that I haven't found an answer to, so I hope that anyone can help me.
I want a user to be able to start my application (WP8), login to facebook / twitter / microsoft / ... .
When he gets authenticated, I want to actually save this user to my own DB so I can add some user specific stuff like preferences, posts, ... .
What do I need to save in my own DB to specify a user?
Do I need to save the token itself or is this something that will be invalidated after a while? Or do I need to specify the user's name? With other words: What can I use as a unique identifier?
And what happens when a user would authenticate with for example facebook and he deletes his account?
And one more question, would you ever allow a user to connect to an application with 2 different service providers? If so, how would you make the coupling of these 2 providers to 1 user in your own DB?
I hope my questions are clear enough!
If not, don't hesitate to ask for more information!
Kind regards,
Gert
I assume that you have your own back-end where you authenticate your own users and your WP8 application is just a client.
First, let me distinguish between a user credential and a user profile. User credential is something that validates who the user is, e.g. username/password, facebook user id supplied with a valid auth token. User profile, is what you store in your own database about the user.
You also need to distinguish between a token you use to authenticate the user and the AccessToken Facebook needs to grant you access to user's data.
So... to answer your questions:
What do I need to save in my own DB to specify a user?
Create a record with user data (like preferences, and your unique user ID), and user's login method (e.g. Facebook) and credential (e.g. Facebook's user ID). This is your user's profile.
Do I need to save the token itself or is this something that will be invalidated after a while?
You can also store the Facebook AccessToken here if you've been granted "offline access" privileges by Facebook, but that is used for Facebook's access by you... not by the user's access to your app/back-end. For user's access you could just use a mechanism similar to cookie-based authentication - it's up to you. You could use the AccessToken as a kind of a "cookie", but you would need to always check against Facebook that it's valid.
With other words: What can I use as a unique identifier?
You could treat Facebook's ID as unique (so long as you never allow another account in your user profile DB to link with the same Facebook account)
And what happens when a user would authenticate with for example facebook and he deletes his account?
It's a good idea to have users still create a username/password combination that works with you site and only rely on Facebook login for convenience. In any case, Facebook provides a "Deauthorize Callback URL" when you create an app profile on Facebook. This is called when a user deactivates your app or deletes an account with Facebook. When you receive this call, you could send your user an email when an auth link to setup a different credential so as to not lose access.
would you ever allow a user to connect to an application with 2 different service providers? If so, how would you make the coupling of these 2 providers to 1 user in your own DB?
Sure, you could do that. Say you'd want to allow a Twitter account as well. You'd need to add a Twitter user ID field to your user profile database.
Here's another tip: create an ASP.NET MVC4 project in Visual Studio - the template includes an example of how to set up a user profile database with OAuth login.
Hope it gives you the high-level overview to investigate further.
I am adding Twitter and Facebook login to a MVC 3 test application using TweetSharp and Facebook C# SDK.
Currently when a user signs in using Twitter I create a user account for that user in a user table and store the id, token, and token secret in a separate table with a foreign key to the user table. Since the id, token and token secret do not expire I can quickly locate the right user account when the user logs in next time using Twitter.
What if the very same user logs in using Facebook next time? Since Twitter does not provide email in their API and I therefore have no common piece of information to tie a user account to either Twitter or Facebook I assume I have to create a new user account for a Facebook login? Does anyone have any experience with this? Are there any ways to solve this?
I identify each user internally with a unique key. I check cookies for the user key when any user hits the site. If there's no cookie I create a new key. add it to the user database and set a new cookie. Once a user completes registration the first time by logging in with any of Facebook, Twitter or .Net membership , that key is forever married to that user.
So when an existing Twitter user logs in for the first time with Facebook, we know who they are because their user key exists. It is basically the same solution as macou suggested. Macou's has the plus of working on a new machine or if cookies are cleared, the cookie solution has the plus of not requiring additional user input.
Not really a solution, more of a work around. I was faced with the same problem and ended up forcing the user to complete thier account profile by asking for their email address before allowing them to proceed any further. This meant that if the email address coming back with the Facebook auth matched the email address created with the twitter signin then I didn't need to create another account.
The bigger difficulty was coming the other way, if the account was created by the facebook auth first. It meant an untidy marry up of accounts.
To be honest the information we got from allowing users to sign in with twitter was not worth the effort and in the end finished up only allowing Facebook auths. I'm not sure how important twitter is to your solution.
Not the perfect answer I know, but I thought I would share my experience.
You can't use just a cookie because I can login as facebook then my wife login as twitter using the same browser, you shouldn't link the two accounts in this case.
I think you need to do more than that:
Use a cookie then
Use name/first name/login name/... to see if they match.
Example:
Cookie id: 18459439731114330636, find user with id = 18459439731114330636. Found, go to 2, not found, go to 3.
Is username/first name/last name/... matches the current user? if yes, link accounts. if not, go to 3.
Create a new user.