I have used Google Sign In to authenticate users with Firebase Auth, and I successfully get back my Firebase User. I want to keep the user authenticated, when they come back to the app. How can I do the same?
Users already stay authenticated. After you restart the app, Firebase reads the credentials from disk, and refreshes the user's token. Since this requires a roundtrip to the server, it happens asynchronously. So be sure to await _auth.currentUser() to get notified of the user's status.
Whenever I'm wondering how to do such things, I look at the FlutterFire sample app. This specific line can be found here.
Yes you need to do the auth.currentUser() function in order to keep users authenticated and the best part is that this function will work even if the user is offline, which makes it very versatile.
Related
I'm writing an offline application that uses the Dropbox API. When a user comes to the application, I'm using the https://api.dropbox.com/oauth2/token (docs) to get a refresh_token, which I store for later use.
I am calling the same endpoint every time the user logs in (unless I've already got the user's data in a cookie). I'm not sure that this is the best way to go about it: I at least need to get the user's account_id, so that I can look up their refresh_token in the database if I already have it. But every time I call https://api.dropbox.com/oauth2/token, the user is redirected to the Dropbox app authorization interface, as if they've never approved the app before.
So I would either like to know how to stop Dropbox from forcing the user to re-authorize an app every time. Or, if that is just how https://api.dropbox.com/oauth2/token is supposed to work, I'd instead like to be able to get their account_id somehow when they visit my page.
(In case it's relevant, the app is still in development mode at this point.)
The https://api.dropbox.com/oauth2/token endpoint is an OAuth endpoint that the app can call to get an access token/refresh token. Being an API endpoint, it does not itself redirect the user to the Dropbox app authorization page.
The Dropbox app authorization page is at https://www.dropbox.com/oauth2/authorize (documented here), and the app decides if/when to direct the user there to authorize the app.
You generally only need to send the user through the app authorization flow (sending them to https://www.dropbox.com/oauth2/authorize and then calling https://api.dropbox.com/oauth2/token) once per user for an "offline" application. Once you do so, you should store the resulting refresh token for that user. You'll typically store the refresh token for that user tied to their user account in your own app.
Exactly how you manage the user accounts in your own app will depend on how it's built, but, as it sounds like this is a web app, typically you would use the user's browser cookies to identify the user when they return to your page so that you can look them up in your database and retrieve their details, such as their corresponding refresh token. (Or, if they're not already signed in to your web app, you would have them do so first.)
Greg's answer is very helpful, and very politely addresses my misunderstanding of the auth flow. (I was revisiting old code I'd written years previously—obviously I should have documented it better than I had!)
In the end I believe that Dropbox was forcing me to reauthorize because my application was in development mode, and had a small user base. When I used the identical code in an app set to production mode, it stopped forcing me to reauthorize. So the “problem” is really a Dropbox security feature, and the solution was just to use production mode.
I'm using firebase authentication for my app and I have the users sign up, login, and log out all set up and going. However, I'm a little confused on how to manage the state of the users login status. Currently, if a user is logged into the app, but doesn't use the app for an extended period of time, firebase doesn't recognize them as logged in. I'm looking at the documentation and the approach is a bit unclear.
Should I be storing a FIRAuthCredential every time the user logs in, and then call reauthenticateWithCredential using that credential?
Firebase Auth only requires recent sign-in for sensitive operations like: deleting a user, changing a user's email or password. These are for obvious reasons. You want to make sure it is the same user before making such sensitive changes. Otherwise, the user is considered signed in indefinitely by the Firebase Auth backend (your assumption that "firebase doesn't recognize them as logged in" is not correct). Of course, a developer may also require re-auth before other operations like updating credit card, shipping address, etc. A developer would check the auth_time on the Firebase ID token. Only in such cases would you re-auth. You should never store credentials such as password on the client to avoid prompting the user to reauthenticate. It is needed to protect the user's account.
yes I think that is going to be right approach or second approach you can try is like when a user press login button instead of directly calling Authenticate User put a check in which last login timestamp value will be stored when user login compare timestamp value and then perform selected operation as you want . NOTE - you will be required to check weather user exist or not , but I think first approach will be better as if you had noticed in many Social apps like kik it ask for reauthentication after a long period of time but first it authenticate user instead of displaying home screen it take to reAuthenticate screen
I'm currently implementing an Oauth consumer service which is going to use Soundcloud as an Oauth service provider as well. But I'm having the following issue with it: Taking Facebook or Twitter example, you go there, you sign in, you fill up the permission form, and you are redirected back to your app. If you go there a second time, and given you are already sign in, you basically skip all steps and are redirected back instantly. That means, Facebook recognized that you already gave permission to that 3rd party service, so it doesn't ask your permission constantly.
And that's what's happening when I use Soundcloud. Basically everytime I redirected the user to the Soundcloud Oauth connect endpoint, the permission form always shows up, even though I already gave permission to that 3rd party service previously. I'm forced to press "connect" every single time, which is a drag from the user perspective (how many times can you give permission to the same entity). My question is: is there a parameter I can use to make soundcloud recognize/validate the previous permission from the user account to that specific 3rd party service? Or is this Soundcloud Oauth design implementation and we have to live with it?
Edit:
Maybe this wasn't clear, but each time I press "connect" in soundcloud, a new access token is being generated and delivered. Since my app uses this access token to identify its users, it doesn't work very well for me that the access token is getting updated everytime I want to log in, making me effectively "sign up" everytime. To sum it up, I want to get the previously attributed token to my account, so I can look up in my database, identify it and log him in.
I'm also looking for a solution which doesn't involve storing state in the client that might get cleaned up.
What you can do is store the user's oauth token in local storage and reuse it in future sessions. That's what happens on soundcloud.com.
A longer explanation:
When you use the Connect flow, the user is authenticated by SoundCloud (either by using username/password, Facebook Connect, or an already-existing session on soundcloud.com), and then when it is successful, your app is given an oauth token for that user. This is passed to the callback page which is registered for your app.
That token is the only piece of information needed to have the user be "logged in". Unless the token expires (by time, or by the user manually revoking it), then you can reuse that in future sessions.
I think I'm a bit confused about your application's design: where and how is the oauth token being used? I think that instead of using the token as an identifier, perhaps the user's permalink might be better? If you have the oauth token, you can find out the permalink by querying api.soundcloud.com/me.
So, I'm just starting to use omniauth and have gotten it working with facebook. I have set it up so that it automatically redirects back to facebook for a new token when the current token expires. Based upon that, is there any reason why I should be storing the token to the db? I currently log user accesses but don't really see any value in logging the token. Would appreciate any ideas on why I should.
thx
Depends on your business logic. For example, do you need to access the user's Facebook details at a later time, even when he is logged out? Or if you are queuing tasks (i.e. running this in the background), do you need to post to his wall a few hours later, instead of this very instant?
Another reason I can think of, is. Do you require your app to obtain a new token via Facebook all the time when the user needs to interact to Facebook via your app? Or would you like to store these tokens in your app, so the user does not need to go through the same process over and over?
It all depends on the kind of user experience you are trying to deliver.
as I started to work with Twitterizer in order to publish on someone's wall I am in confusing time.
There is a page, my case, DefaultTwitter.aspx where is link to authenticate on twitter with token provided. Goes on Twitter and comes back to CallbackTwitter.aspx with outh_token and secret. And so the user is identified. On twitterizer example says:
Step 5 - Store the results
You should now store the access token and the user details. Keep in mind that the
only way an access token will become invalid is if the user revokes access by logging
into Twitter. Otherwise, those values will grant you access to that user's data
forever.
My questions are: - should I store any data in SQL datatable and what exactly(however I hope that is not the case to do so)
somebody said that I should save in a cookie(I thought in session); however then if another user comes then how should I create a button to logout or something like that?
-how will user revoke application access if he would like so?
A live example will be much appreciated as I could not found any on internet how exactly twitter api works.
When your application finishes getting authorization to access the user's data, the result is the access token (represented by 2 values, a key and a secret). Those values are, in effect, the username/password you can use in requests to the API on behalf of that user.* Save those values in your SQL database. You'll also be given the user id and screen name. It's probably a good idea to keep those handy, too.
The user can revoke access to an application by going to http://twitter.com/settings/applications, finding the application and clicking the revoke access button next to it. Your application cannot revoke access for the user.
You asked for an example, but you're citing the example application. Just look at the source code in that sample.
* - That's a simplification for explanation sake. Please don't crucify me, OAuth experts.