I have a website where users can create an account and log in. This is stored in a database on the server. I also want users to be able to log in with Facebook etc, and thus skip the account creation. I don't know how to combine this and keep it persistent in the database. Any good examples on this use case?
Let's first see how logins work in general. When a user is logging in for the first time, a session id is generated for the user and is stored in the browser of the user as a cookie (note that there are mechanisms to store session id without a cookie, but let's assume you require a cookie for simplicity).
For subsequent requests to other pages in the same website, the cookie is also sent along. With this cookie (which has the session id), the unique user can be identified.
So, all that you require to know to identify a user in the server side (upon a web request) is the session id.
Having said that, if you want to include facebook etc into the login mechanisms, you need to do two things:
Connect your website with facebook (you will require a facebook developer account and some keys. Look here). When you do this successfully, if the user selects facebook login, your website should redirect to facebook login page and once the user logs in into facebook account, facebook will redirect back to your website with a token. This token is an indication that the user is a 'real' user. If required, you can use the token to get more details (such as facebook id, email address, name, etc.) from APIs facebook.
The second step is the same for any authentication flow. You need to generate a session id for use by your server and then save the session id in cookie.
What I have specified is the general flow on how your requirement could be achieved. The mechanics of how to do this will depend on the server side technology that you are adopting (such as ASP.NET, Ruby, etc.)
Additionally, if your website requires storing information about the user behavior / user activity, you may need to additionally check if the user logged in via FB already exists in your database. If not present, you can store the user's facebook id or something to uniquely identify the user later. With this as the primary key / user id, you can store user activity (such as inserting a record in orders table if the user purchases a product).
Related
I am creating an iOS app, and am working through the signup/login flow trying to understand how to structure my user model.
I want to allow users to sign up via facebook/twitter as well as using a standalone email/password if they don't want to authenticate through a service.
I am using auth0 to handle service authentication.
What is the standard process of storing / keeping track of my users if some are signing up through email/password, and others are simply authenticating through Auth0.
This is what I've come to so far:
My user model will contain the following properties at a minimum:
_id
name
email
password (will be blank for authenticated users)
auth0_id (will be blank for non-authenticated users)
How I will validate a user on login:
If a user who signs up manually (email/password) wants to log back in, I will check their email exists in my users table and then run a match on their password, if a match - return the user object.
If a user who authenticates through a service wants to log back in, I will make the call to Auth0, check their auth0_id exists in my users table, and then run return the user object.
Does this pose any security issues?
Comments/suggestions welcome!
I recommend decoupling your user and auth0 models from each other. For example:
User schema:
_id
name
email
password
Auth0 schema:
_id
auth0_id
user_id
I also recommend requiring a password on the user schema, and generating a strong password for users that register through Auth0. This will ensure that all users have a "standard" user account regardless of Auth0 and their continuing to have those services in the future (ex: the user deletes their Facebook account but continues to use your service – all they have to do is run through your "forgot password" flow).
Then have a standard login flow and an Auth0 login flow – the latter is the standard Auth0 flow, you check that the Auth0 ID exists and return the joined user record.
Did you consider using the email/password functionallity that is built-in in Auth0? That way you don't have to keep two different logics.
This is probably a repeat. However, the other answers haven't helped me out. So, here goes.
I'm working on an application and we with need to add 'users' to it. We'll be giving the option for people to sign in with Facebook, Twitter and LinkedIn. I've worked with these APIs before, however never combined them globally.
How can I maintain and manage these users that will use different services to log in. I'm confused as to how they would be stored in a database, would I need to have a different table for each different social service or is there a way to implement a table that will house all users in one place.
From what I understand, you're asking how to manage, store, verify users that will be logging in your application through different social services.
This is how we've implemented it through the various projects we've worked with. From the list of services you've provided we've worked only with twitter and facebook, so I can only speak about that.
Setup:
We have a web service that our iOS app communicates with such as when the iOS app needs to make a request call for user login the server would take the user details trying to login and gives back a response where the app would then do whats necessary.
We have a database stored on the server with a users table which is used to verify a user.
That being said, you need to understand whats common between most social services, or to at least know what the property is that is used by these social services to uniquely identify its users. In this case they all use email to identify users.
You'll find that when interfacing your app with these different APIs, they like to use a login session key used for unique logged in sessions.
So on your database you would store whatever details you want to save of the user, but know that you need to store atleast the username, password (encrypted), email (for identification, unique column), and login_session_key.
Just double check that linkedIn does have something like a session key that it creates when a user logs in with that method. Facebook and twitter do. Send at least the 4 main data properties needed (username, password, email, session) to the server You then follow this sort of approach:
New user
If the user that is new tries to login, the server first checks the email provided even exists in the database, if it does not then you sent a response back alerting the user that the user does not exist; your app would then take them to the register screen for example.
If the user is in the registry page, save all the details you want to store of theirs including username, password and email.
Members
If the user logs in the email will exist on the server side, its an existing user so just update the session key that was sent from the app on log in if the password matches, (in some apps these session keys are used through the life cycle of the application being used, with each request sending the same session key and if at any point the session key does not match during app interaction, it can be concluded that the user has logged elsewhere on another device perhaps.
if the password does not matches return the appropriate message.
That's about it really. We're able to store all facebook and twitter users in one table.
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.
I have a website with it's own login/registration mechanism (PHP, session, user and user_profile DB tables with username and password, etc). Let's call this the ABC account.
I just finished integrating Twitter's sign-on using Oauth, available as a "sign-on using twitter" button above my normal login form.
So now I have this scenario:
A user logs on via Twitter. Because Twitter, unlike Facebook, does not proivde access to a user's email address, I don't know if this person who logged in via Twitter is an existing user (in my user table) or not. So I create a new account for them (let's call this the "Twitter" account) and prompt them to merge with an existing "ABC" account by entering their "ABC" credentials. If they do so and everything matches, I store their twitter username, id and token in the DB record for their ABC account. Next time they login via Twitter I know who they are in terms of the ABC account (ie, the accounts are "merged") and all is good!
Except, I'd like to have the ability to have my site send tweets on their behalf, which basically means I need an authorized Twitter connection, which I only have if they logon via the Twitter button, not through the ABC account. The reason is with the latter I have their token_secret, received from the Twitter API callback after signing, but with the former I don't. My first thought of course was to save the token_secret in my DB (with the ABC account record) to remove this restriction, however it seems like this is the equivalent of a password and storing it could be secruity hole?
To boil this down to a question: is it "standard" practice to store the oauth token secret in the DB to achieve what I'm trying to do (which itself seems like a pretty standard function for a modern site)? . If not, what's an alternative implementation?
Update: looking at: Best practices - store Twitter credentials or not? it seems this is definitely not a 'best practice'. But it seems like what I'm trying to accomplish is...not sure how to implement? Maybe some kind of cookie-based solution??
Peter
ps -- BTW, if anyone has a better way to do the account "merge" I described I'd be open hearing about that as well. I did some google searching but really couldn't find anything too useful, although this problem must have been solved many times I imagine??? My understanding is that in the Facebook case the email can be used to "uniqely" identify a user (ie, match them to an ABC account), and do the merge without prompting (although I'm not even sure this is totally secure?).
Storing the tokens that Twitter gives you during the OAuth process is -exactly- how you should be doing it. Shove them in the DB.