Handling Google oauth for multiple linked Google accounts per user - oauth-2.0

Requesting a sanity check on a question of how to structure Google Oauth in my app.
The app I'm trying to build - call it AppX - will let users create an account with the app (ideally with username/password or with Google login), and then the user will be able to connect their AppX account with several of their Google accounts for the sake of pulling up their various calendars. This is handy when, for example, a user has separate personal and work Google accounts, but they want to be able to see both calendars in AppX.
To accomplish this, I was originally going with the oauth2 token model which can happen purely on the client side. I was then going to send the resulting token back to the server to save onto the user object, and then figure out a way to allow the user to do several of these oauths.
However, this SO question is making me think that with that client-side approach, the UX for refreshing the token is jarring for the user. So I'm thinking I actually need to do this on the server-side using these instructions, which will allow me to store the tokens for multiple oauths and create a more transparent refresh token experience.
Is this server-side approach considered best practice?

Related

How can I maintain several Google Sign-In sessions alive to allow users to switch accounts without logging out?

I'm currently trying to build an 'account switching' feature for my iOS App that uses Google Sign-In (with YouTube scopes to get YouTube channel data) & Firebase Authentication.
At the moment, if users want to switch accounts, they have to log out and log back in with another Google account, which is not great from a UX perspective.
My end goal is to allow users to log in with several channels and then choose the YouTube channel they want to see data for, from inside the app, without logging out and back in.
Is there a way to maintain several OAuth sessions alive to let user easily switch between accounts?
I have thought of storing the user's access token locally in a dictionary that would map channel ids with the relevant token but I'm not sure if that will be enough to maintain the state properly or if it will lead to a bunch of bugs.
Any ideas or suggestions are more than welcome.
Thanks.
With Firebase Authentication, there can only be one signed in user at a time. The SDK can't manage multiple signins at once. The prior user needs to be signed out at the time a new signin is processed.

Cutting short on the social login flow

Note: This is the first time I'm trying to implement a social login API, so thanks for bearing with me and helping me out!
I am developing a web application and I have a login and registration system already developed. Now, I am thinking of adding Facebook and Google+ login - with a backend. I went through their docs and other tutorials and they require to implement considerably a lot of things.
But, since I have a registration system already, I thought of doing something like this:
Have the social login buttons on the login page.
When the user clicks on a social login button and authorizes the app, the user data is returned from Google+, for example.
Now, instead of proceeding with the OAuth procedure like getting the user ID, secret ID and contacting their server from my server for token verification and getting data, is it possible to just use the data returned (after the user authorizes) and do the normal registration with the registration system that I already have?
These are the advantages that I see in doing this:
No need of extra code or database fields like token ID, etc.
User can add a password to their account whenever they want and login to the site or access their account by logging in through Facebook or Google+ given that they use the same email ID.
It's enough to use the social login providers' API once - the first time the user logs in (which technically registers the user to the site).
I know the advantages are the same when following the full OAuth2 implementation, but what difference does it make?
Now my questions are:
Is it OK to cut short on the social login as mentioned above?
Will I be losing any obvious advantage doing so (given that I already have a registration system in place)?
If yes, is anyone else cutting short on the flow in their website?
The system proposed by you has certain flaws, especially security related flaw. I would give you to the point answer:
You will send data from client after getting it from google+ or other provider and use your registration process implicitly.
This approach is wrong as I myself as an attacker can send you the data from google+ using my clientid for an app. Will you register or login using the info I am sending? I can pretend to be anyone in your system if you do that.
Is it OK to cut short on the social login as mentioned above?
Will I be losing any obvious advantage doing so (given that I already have a registration system in place)?
If yes, is anyone else cutting short on the flow in their website?
No. (see the reason above).
No. You won't be losing advantage as you already have system in place. Most of the sites have a system in place for normal registration. They give oauth login by leveraging it. Some will say that the password is cumbersome or such, but all famous sites provide login and password including SO.
Now the question comes, how to simplify the oauth system given that you already have a system in place.
I recommend this(I would assume Google as a provider) flow with things starting with dot are what you need to do:
You have a Google login button.
User click on Google Button.
The User is redirected to the Google site.
The user gives you permission.
Google redirects and give you a token.
You can now send info and token to your server. (You need to send only token as backend will get info. Otherwise, a user with valid google+ token for your website can send you any info).
Backend verify token and match that "aud" is equal to your client id. Or it can happen via a library. You will need to give only your client id.
Backend get profile info from token in case of Google+(Name, email) while verifying which you can store as part of your registration process or login process if that email already exists. You can store google id of user also. This is useful as some provider like fb don't always provide email for every account. (For some fb don't give email but for majority of cases it give you the email.)
Backend send back session info or jwt token or any other time bounded process which tells that the user is login.
Your user can login via email also. If he isn't already registered then, then he will need to register. Otherwise, using forget, he can set password or from accounts settings he can set password.
You also need to be careful if the same user is connecting via a different provider, he need to have the same account in your system which you can handle via email.
Kevin,
Authentication is a complex procedure involving lot of measures to ensure security. Hence Web-application/ App developers, delegate this critical piece of work to Identity providers like Google, Microsoft, Facebook etc. These Identity providers are trusted by the app developers and more importantly the consumers trust them too.
Why do app developers provide third party/ social logins? Because, it gives the users of the app some advantages.
They don't have to create new account with the app and remember the new set of credentials. Instead they can use the same credentials they are using with the Identity provider, to gain access to the app. This is huge.
They don't have to trust the app completely, means how the sensitive information like passwords, security questions are handled in the app, as they are not providing any sensitive information directly on the app. Only needed public information is fed to the app from the Identity provider. This is huge too.
No need to worry about the system compromise and leak of sensitive information as all Open ID providers have better security policies in place. This gives consumers a high degree of confidence when using your system through third party logins.
"All the advantages you mentioned will be great for the app developers
at the cost of disadvantages to the consumers of the app."
Lets put the consumer disadvantages on the side and look at the advantages you mentioned:
No need of extra code or database fields like token ID, etc.
You still need code/setup to validate your own tokens. You have to add more logic to verify the external tokens, but the consumers will have the advantage of using the external providers like they are in any other application.
User can add a password to their account whenever they want and login to the site or access their account by logging in through Facebook or Google+ given that they use the same email ID.
This is little confusing as users may choose external provider, so they don't have to remember a new password. Also, the account validation process is different if you use external login vs id/password login. If you are willing to provide both, then you already have the system in place, to verify the account for external logins. Then your first advantage is void and you are better of using Open ID spec.
It's enough to use the social login providers' API once - the first time the user logs in (which technically registers the user to the site).
This approach adds confusion to the flow for consumers. They expect to see a login screen from third party provider for authentication (when they click on google+ or FB), but instead they see your login screen.
Instead of cut short approach, it would be worth to use the complete flow. You might add more logic to handle the token verification with external providers, but, actual complex logic of token validation is delegated to the external providers. This adds no confusion to the end user and they can trust your application easily through social id providers. Even though, users can authenticate through social Id providers, it is always a best practice to have the profile object of that user in your system (without the sensitive information like password).
Since you have your own registration process in place, this may not be a huge advantage. But, please look into the open source implementation of any of the Security Token Service (STS) providers, to see if you can borrow some of the features for validation external providers.
Please let me know if you have any questions.
Thank you,
Soma.

Google Drive API for iOS: OAuth2.0 with an application-owned account

I'm creating a simple iPhone app. The basic premise is that the app will display some data (That I provide online) on the application. The data changes over time, so the app has to draw the data from online and display it. I don't have a significant programming background so I don't want to use my own server.
Thus, I thought it would be significantly easier to just put the data into some documents on a Google account and then access them programmatically via the Google Drive API. I could then update the data in my Drive account and it would get updated in the application. The key here is that I am ONLY accessing ONE account that I own MYSELF. The users' accounts are not being accessed. Therefore the goal is to never have to log in manually. It should all happen behind the scenes, aka, it should look like a server, not a google doc.
With this in mind, it doesn't make sense to show the Google Accounts sign-in page to my users as the standard OAuth2.0 tutorial shows here:https://developers.google.com/drive/quickstart-ios#step_1_enable_the_drive_api
I should be able to access my own data by somehow hardcoding in my username, password etc. Google agrees here: https://developers.google.com/drive/service-accounts#use_regular_google_accounts_as_application-owned_accounts
The above link mentions a "refresh token" that I'm supposed to save. However, I have no idea how to build and save that token, or even for that matter, where to find it.
I've gone through both the basic tutorial and the Dr. Edit Tutorial for iOS, but they both assume that the application is accessing USER accounts not application-owned accounts.
I'm not asking for someone to write the code for me (though tidbits are nice), but if you can point me to a step-by-step guide or related sample code that would help me get started that would be awesome. I'll even come back and post the code that I use!
EDIT: Since I realized that the Google Drive API wasn't something I could use for what I am trying to do, I eventually found Parse which is an awesome tool that handles all the server backend for me and is free at the basic level.
Google APIs objective-C client library doesn't support service (application-owned) accounts, because they are supposed to be used by a server-side apps, instead of clients -- you shouldn't be distributing your private key as a part of an app.
If you would like to distribute content from a service account, maybe you should write a server leg to do the authentication and pass clients credentials in a secure way for them to talk to the API on the behalf of the service account. Or, use Web publishing to make documents universally accessible without authorization and authentication if privacy is not a concern.

Embedding an interactive google calendar in website for multiple groups of users

I am thinking to embed google calendar in my website to achieve the following and was wondering if this is doable in google calendar. Otherwise I have to go find another solution.
I have groups of users with one super user, and rest are regular users as follows:
GroupA
Super User 1
Regular User 1
Regular user 2
etc
Group B
Super User 2
Regular User 3
Regular User 4
etc
Each group have their own calendar. Users in each group can not see the other group's calendar. Only able to see their own group's calendar.
Super users of each group have all access to the calendar (add, modify, delete) and have the ability to control how much access regular users have in their group. (read only? read/write etc)
All users are registered to my website, therefore I am thinking to use only one google calendar account (my own account) to create a calendar for each group. Which leads to a question of authenticating my website to google's API. I need the authentication process to be automatic, hidden away from the user and be done on the server side.
My site is built using PHP/Mysql
Q1:
I have tried the Javascript client library provided by google, however it require the user to type in username/password to log into google so that the authentication (OAuth2) process can work. As mentioned in previous paragraph, I only want the user's to log into my website, they do not need to login again into google account. This should be done on serverside.
I even went as far to create a login form with information prepopulated (hidden from the user, the username/password will be visible in "view page source") and send the request to https://accounts.google.com/ServiceLoginAuth, and make the form automatic submit once the user successfully login into my website. However this causes cross domain issues.
Q2:
I may potentially have 10's of thousands of groups registered on my website. each group may have couple hundred users. Can one single google account create that many calendars?
Q3:
Once the calendar is embedded into my website, it seems to be read-only. Is it possible to make it interactive so super users in each group can add/delete/modify events?
Any ideas/suggestions is much appreciated.
Thank you
No answers? It seems like your question is straightforward. If I understand correctly, you want to access calendars from several Google accounts/users. Each user needs to authorize this access, but they only need to do so once. You could generate these requests and send them out via email, for example. When the user grants permission, Google forwards a grant code to your specified callback_uri. The grant code is extremely volatile. It's used to request a token from Google that apparently lasts indefinitely. So there's no requirement that users continually log into Google.
In Google's calendar/simple.php example. The token is stored as a SESSION variable. Even though the token is persistent, the SESSION variable is not. Users have to grant authorization every time the SESSION variable expires. Storing persistent data in a volatile variable is absurd and probably gives the wrong impression about the OAuth2 token mechanism.
I spent a lot of time writing documentation that I couldn't find anywhere else. Please take a look if you think it might help: http://www.tqis.com/eloquency/googlecalendar.htm
What you're asking isn't possible in Google Calendar.
If you're looking to support thousands of groups and each group needs it's own calendar, then you're saying that you'd need thousands of calendars with access control and you'd need authentication to the calendar to be transparent.

How to verify twitter account?

Let's say I am making a sign up form in which I asked user's twitter ID. How do I verify if the ID entered by user belongs to him/her? In case of verifying email we simply send a verification link which user has to click so how do I verify twitter ID? I have never used twitter before.
The only reliable and practical way to verify that twitter account X belongs to user Y this to do full on “3 legged” OAuth authentication. That being said, you may want to consider if you might be OK with just taking the user at their word on it.
Getting OAuth to work and securely storing the resulting tokens is much easier nowadays than it once was, but is still non-trivial.
Reasons to verify the twitter account, in increasing reasonableness:
You will be making enough server side requests, on behalf of multiple users, that you run up against Twitter’s API Rate Limiting. (Having multiple auth-tokens will allow for a higher API rate)
You need to automagically send tweets and/or follow accounts on the user’s behalf
N.B. do this as opt-in and be ultra clear about when/why you will be doing this, or you will face the justified fury of scorned users
Don’t verify the account if you’re looking to do these things:
You need to send tweets and/or follow accounts on the user’s behalf, and the user will be able to perform a browser based confirmation workflow for each of those actions; use Twitter’s Web Intents for this.
If you just want to pull in real time data for user’s avatar, bio, or recent Tweets Twitter supplies some prefab widgets for you.
All of the authenticated Twitter API Calls can be done client side with JavaScript. Twitter has a js framework, which does not require you to handle and store tokens on your server, to help you with that.
An alternate contact method for password resets, notifications, etc.
Private communication between users on twitter requires mutual following, many users probably never check their Direct Messages (or even know what a DM is), and any messages would be limited to 140 characters. Just use email for all that kind of nonsense.
If you’re just gathering this info to display it on a user’s profile page, in an “other places on the web” kind of way, integrating and maintaining all the server side OAuth pieces is likely too much bother. Just make sure you have a reasonable and clear TOS and an obvious way for 3rd parties to report any of your users who may be claiming a twitter account that is not their own.
If you’re still interested in OAuth, Twitter's Dev page has plenty of resources, including a nice overview of a generic “Sign In with Twitter” “3 legged” OAuth work flow.

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