Google App Engine (python) authorization web services /third party client - python

I have a google app engine project and i want to make my REST API available to third parties. Like twitter API.
Twitter requests the user and password to be sent so thet they can be authorized - can i do this with google user accounts?
I have read somewhere on this site this is not a prefered method as their credentials are entered into a thirdparty app/passed etc.
I dont want to over complicate and redirect them to a googles own login/captcha and so on. I have seen a implementation of this - also with desktop/phone/widgets this may not even work.
Is a solution for a third party apps to call my service - the app calls a page on my site (which asks for login - i just add login rights) the user then logs in and my app then creates a long token that is then passed back to third party app which then stores this in their own repository and pass it as a Token arg in the post/put/delete request.
My REST service then checks the token and against a lookup (token|user key) pairs and allows/rejects the method call.
I could also ask the app for their domain? and store this too. I guess i can read the url of the request on the REST service and check they match etc?
Is this a reasonable solution or am i living in the 90's?

OAuth was created with this situation in mind. It's a specification for the sort of auth-token scheme you just described, and it's reasonably widespread these days.
For balance, see this recent StackOverflow thread.

Related

How to setup python social auth for web app and for mobile app?

We have
An existing Django backend with Python social auth for signing in with Google, providing web-based application and an API for the mobile app.
An iOS mobile app with GoogleSignIn pod.
Now we would like to allow mobile app users to sign in with Google inside the app, and then authenticate them on the backend, so that they can access their personal data via the app.
So my idea of the algorithm is:
App uses the GoogleSignIn and finally receives access_token.
App sends this access_token to the Backend.
Backend verifies this access_token, fetches/creates the user, returns some sessionid to the App.
App uses this sessionid for further requests.
The problem is with the third step: token verification. I found two ways of verifying:
1. Python social auth flow
As described in the docs:
token = request.GET.get('access_token')
user = request.backend.do_auth(token)
if user:
login(request, user)
return 'OK'
else:
return 'ERROR'
This would be a preferred flow, since it already has all the required steps and is working perfectly with the web app (like, accounts creation, defaults for newly created users, analytics collection, etc.).
But the problem is that the backend and the app use different CLIENT_IDs for the auth. This is due to the limitations in the Google Developers Console: when creating credentials, you need to select whether it will be a web app or an iOS app, and it cannot be both.
I tried to use different client ids (then backend cannot verify), tried to use web id inside the app (then the pod does not work), and tried to use app id inside the web (then the backend cannot verify again).
2. Google API Client Library
Another option is to utilize the way from the Google Sign-In for iOS documentation:
from google.oauth2 import id_token
from google.auth.transport import requests
try:
idinfo = id_token.verify_oauth2_token(token, requests.Request(), CLIENT_ID)
userid = idinfo['sub']
except ValueError:
# Invalid token
pass
It worked, but here we're missing all the pipeline provided by social auth (e.g. we need to create a user somehow), and I could not find a proper way of starting the pipeline from the middle, and I'm afraid it would be quite fragile and bug-prone code.
Another problem with this solution is that in reality we also have Signed in with Apple and Sign in with Facebook, and this solution will demand ad-hoc coding for each of these backends, which also bring more mess and unreliability.
3. Webview
Third option would be not to use SDKs in the Swift and just use a web view with the web application, as in the browser.
This solves the problem with the pipeline and client ids.
But it doesn't look native, and some users may suspect phishing attempts (how does it differ from a malicious app trying to steal Google identity by crafting the same-looking form?). Also, I'm not sure it will play nicely with the accounts configured on the device. And it also will require us to open a browser even for signing in with Apple, which looks somewhat awkward. And we're not sure such an app will pass the review.
But, maybe, these all are minor concerns?
⁂
So, what do you think? Is there a fourth option? Or maybe improvements to the options above? How is it solved in your app?

How do I access the Salesforce API when single-sign on is enabled?

I'm attempting to make SOQL queries to the Salesforce API using the Python salesforce_api and simple-salesforce modules. I had been making these requests with a client object:
client = Salesforce(username='MY_USERNAME',
password='MY_PASSWORD',
security_token='MY_SALESFORCE_SECURITY_TOKEN')
a = client.query("SELECT something FROM some_object_table WHERE some_condition")
However, my company recently restricted Salesforce sign-in through SSO only (you used to be able to login directly to Salesforce without SSO), and the funciton is throwing either:
simple_salesforce.exceptions.SalesforceAuthenticationFailed: INVALID_SSO_GATEWAY_URL: the single sign on gateway url for the org is invalid
Or:
salesforce_api.exceptions.AuthenticationMissingTokenError: Missing or invalid security-token provided.
depending on which module I use. I suspect this is because of the SSO implementation.
I've seen the docs about creating a new app through Okta, but I need to authenticate and access the API of an existing app. What is the best way to access this API with Okta IdP enabled? It there a way to have a get request to Okta return an access token for Salesforce?
Uh. It's doable but it's an art. I'll try to write it up but you should have a look at "Identity and Access Management" Salesforce certification, study guides etc. Try also asking at salesforce.stackexchange.com, might get better answers and Okta specialists.
I don't know if there's pure server-side access to Okta where you'd provide OAuth2 client, secret, username and password and it'd be silently passed to login.
If your app is a proper web application that needs human to operate - you can still make it work with SSO. You'd have to read about OAuth2 in general (you saw it on the web, all the "login with Google/Facebook/LinkedIn/Twitter/..." buttons) and then implement something like this or this. Human starts in your app, gets redirected to SF to enter username and password (you don't see password and you don't care whether he encountered normal SF login page or some SSO), on success he/she is redirected back and you receive info that'll let you obtain session id (sometimes called access token). Once you have access token you can make queries etc, it's just a matter of passing it as HTPP Authorization Bearer header (simple-salesforce docs mention session id at top of the examples).
Look, I know what I've written doesn't make much sense. Download Data Loader and try to use it. You might have to make it use custom domain on login but there is a way for it to still work, even though you have SSO enforced. Your goal would be to build similar app to how Data Loader does it. This might help a bit: https://stackoverflow.com/a/61820476/313628
If you need a true backend integration without human involved... tricky. That might be a management problem though. They should not enforce SSO on everybody. When Okta's down you're locked out of the org, no way to disable SSO. You should have a backup plan, some service account(s) that don't have SSO enforced. They might have crazy password requirements, maybe login only from office IP address, whatever. It's not a good idea to enforce SSO on everybody.
https://help.salesforce.com/articleView?id=sso_tips.htm
We recommend that you don’t enable SSO for Salesforce admins. If your
Salesforce admins are SSO users and your SSO server has an outage,
they have no way to log in to Salesforce. Make sure that Salesforce
admins can log in to Salesforce so that they can disable SSO if
problems occur.
(If you have a web app and it's embedded as Canvas in SF - there's another clean way to have the session id passed to you. Again - this works only if you have a human rather than backend integration)
If you check the profiles in SFDC and uncheck the box that requires SSO.
"is single sign-on Enabled [] Delegate username and password authentication to a corporate database instead of the salesforce.com user database. "

External login with Oauth2

I'm working on a Django application with users through Django's auth, on the other side there is an Oauth2.0 server that already has all users and their permissions registered. My goal now is to integrate the Django app with the Oauth2.0 server so we won't have to administrate the users ourselves. This would make it so the when the users want to log into our app they are redirected to the Oauth2.0 login site and then redirected to the home of our app once they login successfully.
I think I understand how Oauth2.0 works but I have a couple of questions I couldn't find anywhere else.
Is the scenario I'm describing possible? As in the users would no longer have to be registered in our app and a 3rd party Auth server would provide access to our app or not.
Once I get the access token after the user login where is it safe to keep the access token? I was thinking I could save to AT as a session variable so as to keep the end user's session linked to his account which is external to our Django app.
Every time the user makes a request I would check the AT I'm keeping, if the verification is OK our app responds with the view, otherwise the user is redirected to the login. Is this flow correct or am I not understanding how this integration would work?
What would happen in the case the user is given more permissions but I hold an old token? How do I handle these cases?
I would suggest using a third-party application, like django-allauth. You can simply disable creating local accounts, and enable a single custom social provider that interacts with your OAuth2.0 authorization server.
As noted here, the process of creating your own custom OAuth provider isn't documented, but shouldn't be too difficult.
Once I get the access token after the user login where is it safe to keep the access token?
Allauth will store the access token in the database. If you want to put it in the session too, you can, but there's no point unless you want the client to make requests to the resource server directly.
Every time the user makes a request I would check the AT I'm keeping, if the verification is OK our app responds with the view, otherwise the user is redirected to the login. Is this flow correct or am I not understanding how this integration would work?
That's fine. If your authorization server has no way to invalidate issued access tokens, though, you can just assume that the access token is good up until the expiration date.
What would happen in the case the user is given more permissions but I hold an old token? How do I handle these cases?
Just use the access token normally. If the resource server indicates that it's invalid, prompt the user to log in again. You will get a new access token for that user that reflects their current permissions.

API registration and authentication service

I'm working on an API registration and authentication service application using python. Developers will be able to register their application (domain name of the application) and a random API key will be generated for the registered application.
Next, the registered application will send the API key to the API service with each API request. API server will authenticate the domain of the incoming request with the passed API key to confirm that the request is valid. I'm using Forwarded Host to validated the domain name of the API request, however it doesn't work as in some cases (when the opened page is the first page), Forward Host comes blank.
Are there a better approach to authenticate the request or any changes required in the API registration process to reliably authenticate the request? Some pointers will be helpful.
Using Authorization proxy
Samples are "3scale.net", offering free tier, other commercial solutions exist too.
Open source solution I am aware of is ApiAxle, which is much simpler, but still very useful.
The proxy takes care of managing access keys and forwards request back to real application only in case, it is really to be served.
Using Authorization service
Another solution is to have some internal service evaluating set of client provided keys (providerid, appid, accesskey, ...) are authrized or not. For this purpose, you have to:
set up authorization service
modify your code by adding 2-3 lines at the top of each call calling the authentication service.
Sample code for 3scale is here: https://github.com/3scale/3scale_ws_api_for_python
Conclusions
Authentication proxy makes the application simple and not bothering about who is asking. This can be advantage until your application needs to know who is asking.
Authentication service requires changing your code.

How to implement authentication for REST API?

I'm creating a web based service that I want to expose as a REST API so that developers are able to create apps using it. I want developers to be able to create/manage user accounts and authenticate through API. How to handle this? OAuth or something else?
I'm using python,flask,mongodb for this.
We have settled on the following, using OAuth 2 (which is much preferable to OAuth 1). In particular we are using the resource owner password credentials flow. As to how to integrate it into our RESTful service, here is the idea:
The initial resource, when hit by an unauthorized user, returns a 401. The body of the 401 contains a single link, with rel=oauth2-token. (How you signal links depends on your media type; we're using HAL, but you could use even just the Link header.)
After the user authenticates, he returns to the initial resource, sending in his Authorization header the bearer token returned from the OAuth 2 process. At this point, we return a 200, with all the normal links available.
We don't expose account creation, but if you wanted to do that, I would do so with another link available to unauthorized users in the initial resource. That link would have a custom rel since it is specific to your application, e.g. rel=http://rels.myapi.com/users
Good RESTful design would indicate that the link with this rel points to e.g. http://myapi.com/users, and that consumers of the API do a POST to that endpoint, which returns to them the new user resource with a Location header pointing to the newly-created user resource at e.g. http://myapi.com/users/username. (User resources themselves would of course be another rel, distinguishing between the singular user resource and the plural users collection resource.)

Categories