I am using Google App Engine with it's default OAuth Service. I can easily access it with the help of Google OAuth Java Client Library - I get the request token, user authorizes and everything work just fine.
My question is - is there a way to access my API without user context? So called application-only method (see Twitter) (in OAuth2 it's called client_credentials?
Because some of my API methods (on my personal Google App Engine application) really don't need any user context - just a consumer key so I can identify and measure my API consumers.
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I have a scenario where I have an on-premise GUI application which has a "Web Service Invoke" component which I use to call a GAE API.
In the GUI application, it is possible to:
store credentials
create a chain of web services/http(s) calls that can integrate an output of preceding https(s) call as a query parameter or header value into the next http(s) call
retrieve a value from JSON response of the http(s) call
But it is not possible to programmatically do anything. The Web Service widget has fields for passing API URL, query parameters and headers only.
I'm looking to do a service-to-service authentication for the API call and the API should be protected using IAP as well.
I'm aware of the recommended approach is to create a service account and provide the service account JSON key file to the client and the client signs a JWT token and pass it as a bearer token. But as I only have widgets, no programming possible, therefore signing JWT token is not an option.
I was looking at Google OAuth or IAM APIs which can support "client_credentials" grant type wherein I can get an access token using just clientId and clientSecret - something possible in Apigee. But it seems this grant type is not supported by Google OAuth APIs.
I also looked at Cloud Endpoints using API KEY - so the current thought is to the client passes API KEY in header/parameter for authentication to Cloud Endpoints, then Cloud Endpoints uses its service account to get access through IAP, and finally, I'm thinking that the client can also send in "Basic Auth" credentials through Authorization header which the GAE API backend service validates. The additional "Basic Auth" is because Google recommends using another auth method in addition to API KEY.
I would like a simpler solution if possible using GAE and IAP only. Any other suggestions, especially using time-limited tokens, that can work over only http(s) calls (non-programmatic or client library), is much appreciated.
Any alternatives or things to try is also appreciated.
Look into this server-to-server authentication using JWT Google API Authentication
I have an angular web app talking to a c# .net web api back end.
They are both hosted on azure app services.
Azure app services offers a suite of authentication services and I've chosen to use google auth.
I've got my google client id and secret setup in azure google auth and my web app correctly shows and prompts me for my google credentials.
My problem now, is that i need my web api back end to authenticate the web app google token. I couldn't find any articles or tutorials that demonstrates the following:
How to get and send the token to the web api? I've read that azure app service should automatically inject the necessary auth headers but any calls to my api do not include those headers. Should i manually call auth/me and add them to the request header?
How do i get my web api to authenticate the details from the request header with google auth? Do i need a separate client id for the web api or should i re-use the web app client id?
Cheers!
According to your description, I assumed that you are using the built-in Authentication / Authorization provided by Azure App Service.
AFAIK, App Service Authentication (Easy Auth) provides two flows: client-managed and server-managed flow. For the server-managed flow, the server code manages the sign-in process for you, and your backend would directly receive the token from the relevant identity provider (e.g. Google, AAD,etc.), then both generate a authenticationToken for browser-less apps and AppServiceAuthSession cookie for browser apps. Details you could follow Authentication flow.
For your angular web app, you could just use server-managed flow, after user successfully logged, you need to call https://<your-angular-app-name>.azurewebsites.net/.auth/me to retrieve the google access_token, then send the following request against your web api endpoint for retrieving the authenticationToken as follows:
POST https://<your-webapi-app-name>.azurewebsites.net/.auth/login/google
Body {"access_token":"<the-google-access-token>"}
After successfully retrieved the authenticationToken from your Web API endpoint, you could send the following subsequent requests for accessing your APIs:
GET https://<your-webapi-app-name>.azurewebsites.net/api/values
Header x-zumo-auth:"<authenticationToken-generated-by-your-webapi>"
Moreover, you could also use client-managed flow in your angular web app, you may need to directly contact with your identity provider (Google) to retrieve the access_token in your client via Auth0 or google-signin or other third-party libraries. Then you may need to both send request to your angular web app and Web API web app for retrieving the authenticationToken as the above request sample.
Do i need a separate client id for the web api or should i re-use the web app client id?
Per my understanding, you must use the same google application. For AAD authentication, you could configure a AAD app with the access permissions to another AAD app.
I currently have two app services
Web App (Asp.net core 2 w/ front end in react)
Web Api (Asp.net core 2)
Note: Both are configured with different Azure active directory app id.
user signs into Web App and retrieves a token for it's own appId/ClientId/ClientSecret stored in tokencache.
from the WebApp, the user wants to talk to a WebAPI but needs to get a token since it's protected with AAD as well but it's a different app id/client id/client secret.
Problem:
When I try to do a AcquireTokenSilentAsync() for the web api, I get an error throwing that I the token is not in the cache?
It also seems that with depending if your using AAD v2.0 or v1.0 will determine if the web app and web api can have different app ids. So it seems like i would have to use AAD v1.0. With Asp.net core 2, it's not clear to me what OpenIdConnect is using or configured to use under the covers.
Question:
It's not clear to me why the acquire token silent async didn't work and failed. Does that only look for the token in the cache; otherwise it fails?
Is it possible to configure the token from web app to have permission to access web api resources. I notice that in the azure portal, you can selected resources like microsoft graph, but I don't know how you would associate a custom API. In my case, I want to get it running on my local machine before I move it all to azure.
If the web app token does not have permission to access the web api, do i need to do another login authentication with the user even thou both are within the same tenant?
Any Advice appreciated,
Derek
Yes, AcquireTokenSilentAsync will look into the cache, and see if it can find tokens. If it does, it will check to see if the access token is still valid and return that back. If the token is expired, it will use the refresh token to fetch a new access token and return that back. When this call fails, it's an indicator you need to perform an AcquireTokenAsync (which will likely show UI in the case silent already failed).
Yes, you can associate a web app to get tokens for your own custom web API. I'd recommend using Azure AD v1.0 (register the app in the Azure portal, ADAL library). You'll need to register the two apps (web app and the api), both will be type web app/api. In the API, you can register an App ID URI which will act as the resource identifier for this API. In your web app, you'll want to go into the Required Permissions, and add the Web API you have registered as a permission. Then in your web app, you'll need to use the ADAL library (alongside an OpenID OWIN middleware) to acquire a token for the resource as specified by the App ID URI field. Here's a code sample that implements the exact scenario you're describing (Web App/API in ASP.NET Core).
I want to implement some form of access control for a REST API implemented in App engine. Is it possible to get the list of GAE Applications that a user has permissions to administer or view in the app engine console. Or whether the user has permissions to administer/view the current application.
Note: the Users API does not work for me because this is a rest server called by another google app not a web service called by a user from the browser. OAuth API seems promising but I was unable to find an OAuth scope or rest endpoint for getting GAE related information.
there is no API that can provide a "list of GAE Applications that a user has permissions to administer." Google Cloud Endpoints on App Engine (Trusted Tester program) may be useful for hosting custom RESTful APIs with user authorization may be useful, read more here: http://endpoints-trusted-tester.appspot.com/
There must be an API as the Google Eclipse plugin is using it.
https://developers.google.com/eclipse/docs/signin?hl=de
But it is not documented.
I'm trying to figure out how to implement the following authentication flow:
The user accesses a web application (most likely to be written using Ruby on Rails) and authenticates (e.g., username/password).
The client consumes data via AJAX provided by a RESTful API built on Google App Engine (Python, webapp2).
Requirements:
Only users authenticated in the web application (Rails) should be able to access the API hosted on App Engine.
Users can have different roles in the web application (Rails), and the API (App Engine) needs to know what roles are associated to the given user to restrict access to certain data.
The client should be able to call the API (App Engine) directly via AJAX, without routing all requests through the web application (Rails).
I'm looking for suggestions on how to implement such workflow. Should I use OAuth (or OAuth2) for accessing the API? Should the OAuth provider live on App Engine and the web application (Rails) ask the API for a token on behalf of the user? If so, what is the best way to allow only the web application (Rails) to request OAuth tokens? Or should I consider a completely different strategy?
Any suggestions are greatly appreciated. I'm also looking for suggestions of libraries to implement OAuth in the context above.
I suggest you use caution if you are considering implementing an API built on the Google App Engine using OAuth for your security layer. I am currently involved in a project that is struggling to solve exactly this problem. The OAuth layer over the GAE is still new and considered by Google to be "experimental". Google's documentation is minimal at this point. What there is begins here. I wish you the best if you try to proceed, and I will do my best to offer help if you do.
My solution to this same problem was to write my own three-way authentication (like OAuth):
After the user is authenticated on the RoR server, it responds with a temporary token. This token is stored on the RoR server, is good for 60 seconds, and contains the user's roles.
The browser sends this token (using AJAX) to the webapp2 server. It's like logging in on that server using just the token.
The webapp2 server forwards the token on to the RoR server to make sure it is valid.
The RoR server makes sure the token hasn't expired and immediately deletes the token to prevent duplicate requests. If the token is valid, the RoR server responds with the user's roles.
If the response from the RoR server is good, the webapp2 server responds to the browser's AJAX call (in step 2) with a cookie indicating that this user is now logged in. The session should contain the user's roles.
Subsequent requests to the webapp2 server will include the cookie so that server can respond according to the user's roles.