I'm managing authentication state in a readable store which is grouped with a promise that resolves when the auth state is known (either signed in or out). The store is set internally via onAuthStateChange.
I'm trying to access this auth state from the server (+layout.server.ts and +page.server.ts) so that I can redirect the user to a sign-in page if they aren't authenticated, or load data from the database if (and only if) they are. No matter what I try, whenever I access this store from the server, its value is always null. I think this is because Firebase is only supposed to run on the client, although I'm not sure. Is there any way I can access this store from the server, or change my implementation so that Firebase runs in the server and passes auth state to the client? This blog post explains pretty much exactly what I want to do, but the solution here seems more complicated than it needs to be.
I've tried moving Firebase initialization code to the server (in both hooks.server.ts and +layout.server.ts), but there's no way for me to pass the auth object to the client because it can't be serialized (I get an error explaining this when I try to return it from a load function in +page.server.ts). I've also tried to handle authentication only using client-side code, but the server is responsible for loading data from the database, so in this case there's no way for me to verify a valid authentication state from the server.
author of the blog post you linked here.
You are correct in that the firebase client is only supposed to run on the client. If you want to access the Firebase services server-side you're supposed to use Firebase admin.
In my post I'm working around these limitations that firebase sets and unfortunately you do need that much code.
You are forced to do all the authentication in the frontend (firebase-client) and only afterwards you can inform the backend of the user info. (through the cookie)
Before I wrote this the ideal solution I had in my head was this:
Send the user to a login page that lists all the possible login providers.
The user chooses one and logs in.
the user gets redirected to a callback page where we can do something with the auth data in the backend.
I do think that something like this flow is possible if you're using custom tokens. But I'm sure that will be a whole load of even more complicated code.
Related
I want to use Firebase Auth for my user login/registration process. Everything else should be handled by my own backend (spring boot app + postgres db).
Now I'm asking myself how I can synchronize a new created user to my user table in postgres. I thought about the following:
REST call through client - Everytime I get a success event from the firebase sdk I call an additional request to my backend which sends uid, username etc.
Problem: What if my backend call fails but the register process was successful ? That would lead to an inconsistent state since (at least thats what I understanded) I can't easily rollback. That would lead to situations where a user can login into my app without my backend knowing the user. This would crash/ invalidate all my following queries (e.g. search after user xyz would lead to no result even though he/she exists)
Check the existence of the user in the postgres database
Here I would query the uid from the database (which I got from the jwt) and create a new user if it doesn't exists in every incoming request.
Problem: The user query is a unnessecary overhead for every incoming request.
Trigger with cloud functions - When I understood it right firebase auth is firing events when a new user is created in cloud functions. This could be used to make the external api call.
Problem: I dont know what happens when my external rest call fails at this point. Can I rollback the registration ? Will I be ever catch this event again ? I also proably would have an eventual consistency situation, since I dont know when the cloud function triggers. Furthermore I would prefer not to include cloud functions to my stack
Is there any way how I could do this in a transactional manner ? Did anyone else tried is using sth simular ?
Thanks for every help!
The easiest way is actually to not synchronize auth data, but instead decode and verify the ID token of the user in your backend code.
This operation is (by design) stateless, although Firebase's own backend services often implement a cache of recently decoded tokens to speed up future calls with the same ID token.
Apparently, I finally came up with a different solution:
Register user per Firebase SDK (e.g. with email + pw method)
Make a post-call to my own registration api including the resulting uid from the previous step and some metadata
API creates a new user including a column with the UID + Fetches the firebase token of the user and adds an internal claim that references to the internal Postgres UUID via Admin SDK.
Frontend gets the created user and hard refreshes (very important, since the previously fetched token won't contain the newly added claim !) the firebase token and verifies that it contains the token. If it does -> everything is cool, if not some oopsie happened :) That will require a request retry.
Later when you start your app you can just check if the passed token contains the custom claim, if not open the sign up/sign in page.
Every endpoint except the one for registration should check if the claim is set. If not just forbid the request.
How to set custom claims:
https://firebase.google.com/docs/auth/admin/custom-claims#set_and_validate_custom_user_claims_via_the_admin_sdk
You can use the Firebase Admin SDK to create the user account from your back-end instead of from the client.
So first you create the user in your database, then grab the ID and use it to create a user with the same ID in Firebase.
If all goes well, send a confirmation to the client and sign it in using the same credentials they entered.
Why not creating an endpoint in your backend service and call this endpoint when a client side authentication succeeds?
This method should do 2 things:
decode token to get access to Firebase user object (Firebase Admin)
Compare Firebase user with your internal user table. if it doesn't exist you can create it using firebase user object, otherwise do nothing.
This solution allows you to do other nice things as well (Syncing user info between Firebase and your internal db, providing a way to let a frontend know if this user is new or not, ...) at a relative small cost (1 get call per sign in)
Given a backend wrote in nodejs that returns a page that should either link to login (if the user is not logged in) or a link to logout (if the users is already logged in).
Considering I'm using firebase as authentication tool, how can I know in the first request, when the user is accessing the website, if is he authenticated to then
set the ejs template to respond with the correct link ?
Is there some header, or token that can I use ?
The only solution I found was use ajax after the server response, but I don't like this solution because apparently there is a delay in the link renderization.
As far as I know there is no way to know if the user is authentication on the initial request. From a quick inspection no data is sent along with that request. That kinda makes sense, given that upon this request it is not even known if you're using authentication to being with.
Update
I actually just ran into this blog post from one of the Firebase engineers, which seems promising: Introducing session cookies for server-side web apps. I haven't fully read it yet, but the title sounds like it may be exactly what you want.
I have a Chrome extension that communicates with my Meteor app through a REST API created with the Restivus package.
The user authenticates to the REST API and then uses authenticated tokens to make any further requests.
So far, everything works fine, as long as he stays within the extension. However, from the chrome extension, I'd like to redirect the user to his profile page on my main website. When that happens, he's no longer authenticated, and must re-sign-in to access the profile page.
I figure this is because the REST API session and the webpage session are two completely different sessions on the server (even though both the API and the webpage run from the same server). My question is, is there a way to maintain the user's logged-in state as he moves from the extension to the main website?
I figure there are a few options:
I'm using the standard meteor accounts package. Is there a way to push whatever standard cookie / data that the accounts package uses, to the user's browser, so that when he goes to the website, he'll be considered logged in?
Push a custom cookie to the user, which I then check for and log him in when he first comes to the website. However, I don't know how to push a cookie through a REST API or generate one in the Chrome extension
Use DDP to communicate with the second session and transfer the login credentials.
I don't know if these are the best options (or even how to implement them if they are...). Has anyone figured out a way to do this already? Thanks!
I would suggest you to develop your own flow of authentification using a token as an URL parameter. You should achieve a similar experience that slack provides with magic authentification links
The idea is to generate a token and add it to the Meteor.users collection for the user logged in your chrome extension.
Then, redirect your user to an url with the token as a parameter. The app checks which user is linked with this token and log him in.
You can get inspiration on what is done in the account package to handle enrollment and reset links, or in the passwordless package
I'm building an installed application that will have features requiring the Google Drive REST API using Qt and C++. I understand Qt is now releasing new libraries to support OAuth flows but let's assume I'm a student and learning to use OAuth at this layer is a requirement for this project.
In my application, I have a working OAuth flow for installed applications that ends with an Access Token and Refresh Token being stored using QSettings (I'm open to input on whether this is a disastrously bad idea too). The application requires no authentication/login for its own sake/data, but it does need authentication to Google for calling API's using an Access Token. This application has no associated web backend being hosted; its simple and should be deployable completely locally (I've written and included a simple TCP server that will receive the authorization redirect_uri and will run and close when called from within the application).
As such, I'm curious about the best way to make sure that, when a user opens my application and wants to use the Google Drive features, they are appropriately authenticated on Google's end. Say, if I maintain an access token in the registry, and this access token is granted per-user/per-application basis (right?), then how can I make sure only the user the token belongs to is able to make calls to the API with it?
Here's my understanding and approach; feel free to correct me or educate me if I've got the wrong interpretation.
If an Access Token is found, perform the following:
Open a browser page to a Google login domain and have the user authenticate there (this could prohibit a user from being able to use a cached login session that would have access to a token they otherwise shouldn't have access to)
If user has correctly authenticated with a Google account, return control to the application and make a test call to an API using the stored token.
If the call fails (responds with an invalid_credentials) I should be able to be sure its because the access token has expired and the application will go through the flow to renew an Access Token from a Refresh Token.
If no Access Token is initially found:
Start a normal OAuth installed application flow
Get the tokens and store them so that when the user opens the application next time the former procedure is used
My issue then is the first two steps if the Access Token is found. Nominally this could be done by the typical OAuth flow but it appears that when using a localhost as the redirect uri, Google will always prompt for consent, regardless of settings for prompt and access_type authorization query parameters.
What can be done to accomplish these first two steps in a way that my application can control (i.e. not a solution that relies on a backend server being hosted somewhere)?
If this question is too open-ended for SO requirements I can make some more restrictions/assumptions to limit the problem domain but I'd rather not do that yet in case I unknowingly rope off a good viable solution.
Thanks for reading! Sorry if its a verbose; I wanted to ensure my problem domain was fully fleshed out!
If you are using an installed application, I wouldn't recommend using or storing refresh tokens. Storing refresh tokens on the client side means that if an intruder gains access to the client's application, they have infinite access to the user's application without ever having to enter the user's credentials. If you do insist on having a refresh token, ensure you follow the Google's installed app flow, with the code_verifier parameter included in your requests.
If the access token is found, you should try to verify it, and if verified then use it at the google api, otherwise force the user to login again (or refresh it if you chose to still use refresh tokens).
If no access token is found, your flow sounds fine.
A few notes on loggin in with Google:
Google will only return a refresh token if you specify access_type=offline in your auth request.
Google will only return a refresh token on the user's first authorization request, unless you always specify prompt=consent in your query params.
In my experience, when leaving out the prompt query param, the user is not prompted for their consent again. If they are logged in to google, you will get a new access token, but no refresh token, unless you have prompt=consent.
I think the idea is you use prompt=consent if you have no record of the user ever using your application. Otherwise if they have used it before, you may prefer to use prompt=select_account to allow the user to select which account he wants to use in case he has more then one, or you can just use prompt=none.
This is just my understanding of it all.
My approach I ended up using was just to deploy with an SQLite db that will be stored in the AppData roaming directory. The db schema includes a field for the user's Name (from the OpenID IDToken field if it exists), the user's picture URL (again from IDToken if it exists), the refresh and access token strings (will be stored as encrypted strings when I get around to it), the user's UID/sub string, and a field for a user name and password.
These latter two fields are authentication fields for within my own application, which, again, I wanted to avoid but it seems impossible to do so. So the user will be prompted to enter a username and password into a form, and these credentials will be checked against the existing SQLite db file mentioned previously.
If they exist and are correct, the user gets logged in and will have access to their respective access and refresh token.
If the user has forgotten their password, they'll be asked for reconsent (going through the installed app flow again), and whatever password they provided during initial login will be used as the reset password. It is considered, for my purposes, that logging into Google for the installed app flow is proof enough that the user account belongs to them and they should have authorization to reset the password.
If the user is a new user and doesn't have a record in the local SQLite db file, then they can also click a button to "Create New Account" - which effectively goes through the authorization flow as well but this time a whole new record is posted to the SQLite db with the appropriate fields filled.
There's still more optimization that could be done but at least I am getting closer to the level of security and control of access to Google user accounts that I want.
I'm not marking this as an answer because I feel like this solution is still not desired and that there should be an easier way. So if someone has evidence or experience of providing an equivalent level of authentication control without needing to maintain a local user account database then I would be more than happy to mark such a method as the solution!
Thanks again!
How can I create a firebase user from the node.js client? I see that there is a simple-login but that looks to be used from the web browser. I would like to authenticate with my firebase secret and then call the createuser api somehow.
The way my system is built the clients only send requests to the backend for processing. This way I have a log of every action taken by every user and I can guarantee that each alteration is applied to my other databases as well before it makes it into firebase. Also I do not want users to be able to create other users. Firebase is just a workqueue for me mostly but I am also using the simple login to verify the user then swapping them over to a login token afterwards to get the ability to check custom permissions in the auth on security rules.