I am looking for a pattern/technical solution to the following problem.
I want to have two types of mobile apps, call them Client and Admin. Client would allow one to enter their "client number" or scan a bar code. Upon submission, the following would happen:
1) REST call to a cloud server app which would record the client signing in (got it covered);
2) REST response to the Client app identifying a successful sign-in (got it covered);
3) Call to Admin app identifying a sign-in (successful or not) with client's details (unknown).
I am not sure how to accomplish #3 as it would be the cloud server app pushing information to the Admin app. There could be multiple Client apps and more then one Admin app. Details of all client interactions would have to be pushed to all Admin apps.
I am looking for suggestions. Thanks.
Related
This is in relation to my other question about the need to create a Facebook app.
I've been reading a lot about how to best approach login for mobile apps users (iOS and Android) that access my web service running on Google App Engine. I'm still not clear how to best do it as I would like to offer login with both Google and Facebook. The app and the web service does nothing with Facebook or Google other than I would like to piggyback on their login.
Having only login with Google for GAE is very easy and the same goes for using OpenIDConnect. Facebook unfortunately does not support this.
Reading an old question here on SO where someone wanted to do the same as I it looks like the app should do Facebook Login and then get a token that it passes to my backend which needs to be validated by contacting Facebook. Is this how to do it today?
I also found Google Identity Toolkit, which seem to be what I need. However, I do not have a website or just apps. I would need to have the apps do the Facebook login and somehow provide my web service with something so it can validate the login info.
Later on an app user should be able to log in using randomly Facebook, Google and my custom username/password. The app and the web service should know the user is logged in and authorize it to access the REST API.
How do I accomplish this? BTW, I'm using Go on GAE.
I would really appreciate if someone could explain if there are several options how to do this, pros and cons, and provide an overview of the best approach and what needs to be done.
Many thanks for any help with this!
UPDATE
OK, thanks a lot everyone for the help and pointers. I have successfully run the quickstart sample app for iOS for my GAE backend. Basically, created a Facebook app and permissions credentials on my web service on GAE so that the sample iOS app can log in.
A bit of a gap still before I have an authenticated user in the datastore and can authorize successive API calls.
Main open questions at this point:
how to get the gtoken in the iOS app after successful Facebook or Google login?
should I explicitly call an API on my web service to pass in the gtoken or is this somehow automatic with Gitkit API enabled?
Thanks for any help!
UPDATE
To answer #1 and #2 myself, there's a "successful sign-in url" that can be given in the app engine config so the app knows where to call with the gtoken. Then after that it's like explained in the answers.
Looks like you have an app and a backend on GAE.
If you are using google identity toolkit, it will allow you to signin with Facebook, Google, and email/password.
When user successfully signs in to your app using identity toolkit, your server should receive a gtoken. You have two options here:
Pass the gtoken to your app and save it there. When your app makes API calls to your backend, you app should attach the gtoken to every request. Your backend should verify the gtoken(https://developers.google.com/identity/toolkit/web/required-endpoints) for every API that needs authorization.
Verify the gtoken, generate a token that your backend can recognize/identify the user. Then pass the token to your app and everything else is the same as option 1.
If you do not want to use identity toolkit, you can implement facebook login on your app/backend and use facebook token to communicate between your app and backend.
Whatever your decision is, apps that use your API should pass you something that your backend can recognize/authorize the user.
The answer is about using Google Identity Toolkit (GIT). GIT itself is an identity provider, which would be integrated with your apps and backend. The flow works along these lines:
your app requests login via its GIT API
GIT will perform the federated login with Facebook or other 3rd party provider (transparent to your app) and returns a GIT token to the app (representing a unique user from your end-to-end system perspective, i.e. apps plus backend)
the app makes a request to the backend in which it passes the GIT token
the backend verifies the GIT token validity (using this go GIT client API, for example) and from it can extract the identity of the user and thus validate the request
You can find more detailed info about the backend token validation in the backent endpoint doc, look for these sections in particular:
Understanding the Identity Toolkit cookie/token
Getting information for users
Now the actual token validation on the backend may take a few seconds, so it might not be practical to do it for each and every REST request from the app. If so you'd need to somehow:
save the info that the user of that specific app instance is
authenticated in something like a "session" managed between your app and the backend
map a specific REST request received by the backend to a specific such authenticated "session"
But I'm not sure how exactly is this "session" functionality done in the apps+backend context, I didn't write any apps yet.
Having just implemented this, I have a pretty basic question about how authentication and oauth work together. I have a sample web app client (ckclient) that accesses a REST API (commitapi) for managing their commitments. This follows the model of having an app like LinkedIn displaying a user's Tweets (via Twitter) as described in: http://www.slideshare.net/coldfumonkeh/oauth-demystified-hopefully
In my simple app, a user goes to the web app client and asks to see their commitments. I am using Restlet and the user is redirected to a page where they can choose their OpenId provider and login. They are they redirected to a page where they can approve access to their commitment resources. Everything works fine.
But, the web app client doesn't know who the user is! All the authentication is done with the REST API, not with the web app client.
So my first question is... is this a bug or a feature?
My guess at the answer is that this is a "feature" - that is the way Oauth works - you don't WANT the web app client to know the userid/email address stored with the resource server (commitkeeper in my case, Twitter in the slideshare above).
If that is correct, then if I want the web app client to know who the user is, the web app client should provide user authentication. Since I am using Google's UserService on the server side, I also implemented UserService based authentication on the web app client. And now, if the user also does the web app client authentication, then the web app client has the identity of the user. So that is all good.
Combining these two also works - but I can't quite understand why.
On the web app, I login through Google's userService (technically with a GaeAuthenticator, that only uses Google accounts). Now the web app knows who I am and can display my email address.
From the web app, I ask the server for my commitments. The server responds by giving me the login page where I can pick my OpenId provider.
2a. If I pick Google, the UserService seems to know that I have already logged in through the web app and shows me my commitments.
2b. If I pick Yahoo (or something else), I have to authenticate with Yahoo and then I am shown the commitments for that Yahoo user.
This all seems fine to me - except for how does the UserService know that I already logged in? The webclient is at x.appspot.com and the server is at y.appspot.com. Is the answer as simple as the UserService is integrated across all of appspot.com?
In any case, thanks to anyone who can answer these two questions - or just confirm that I am on the right path.
(Note: I am using Google's UserService to create the login urls, my web app client and resource server are on appspot, using Federated Authentication, and all this is Java).
Well, the answer to the first part of the question is "feature" - getting resources from a ResourceServer via OAuth is not supposed to expose any user related information to the web app client.
I will pose a more specific question regarding how the UserService does its magic.
I am developing an app to be hosted on Google App Engine. Users will be able to use their Google IDs to login to the app. The app also has a client counterpart in the form of a Blackberry Application.
My question is - is there a suggested way for my app to collect the user's Google credentials so that I can authenticate it against Google using OpenID semantics? In Android, for example, I can use the Accounts API so that I don't need to explicitly ask the user to enter credentials. What's the way to do this in Blackberry?
I see 2 ways, neither of which is ideal:
Write my own form in my native Blackberry app where the user enters Google ID and password, which I then use to obtain the authenticator token and perform the rest of the authentication behind the scenes. But the point is - it is inappropriate to ask a user to trust my app with their Google credentials.
Use standard Google Open ID Authentication mechanism - which opens up the web browser and displays Google's Open ID login page. Although this is a one-time thing (after which I can save the authentication token so that future requests to GAE do not require any prompting for credentials), the user experience is still disruptive since it involves opening the browser in addition to my native BB app.
So, what's the suggested way forward?
Using the browser to authenticate is pretty much the only standard way to do this. A number of Android apps do this for OAuth or OpenID endpoints too. Depending on how the Blackberry's protocol handlers work, you should be able to set a continue URL that results in your app being called back by the browser when authentication completes.
At our company we are experimenting with the Google App Engine.
There is already an app online and they wanted to add me to this existing app.
We tried to do this several times but I still can't access the existing app.
The email you receive when you are added to an existing app consists of 2 links.
- one for coupling it to an existing Google account
- one for coupling it to the receiving email address which is a Google Account
If i follow the link in case 1, I'm redirected to a page where I need to create a new application.
If i follow the link in case 2, I get the following Server Error:
"Sorry, you've reached a login page for a domain that isn't using Google Apps. Please check the web address and try again."
If one of my colleagues looks at the Permissions page of all users, my status is pending...
Anyone an idea?
Your accounts are on Google Apps? if is the case, you need to use the good link; In the email you received you should have 2 links to validate account. The first is for google account and the second is for google apps account.
Discovered a problem with connecting all together - Facebook, GWT and App Engine.
I need to authenticate user on my web site hosted on App Engine (Java) that uses GWT. After authentication, some information should be passed to server from facebook - like profile information, user list, etc.
Currently am trying to use facebook4gwt and authentication works fine, and I can obtain all needed information on client side, but can not transfer facebook session to server, particularly, obtain Facebook cookies for session verification.
Could anyone suggest any good solution for this? Probably, it would make sense to get rid of facebook4gwt and do everything on server side.
I have been using the gwt-facebook library for one year to authenticate users of my application on App Engine. When a user is already logged into Facebook, and has already authorized my application, I can automatically get the access_token in GWT and send it to the server which can then do the hard work (data syncing) with facebook-java-api library.