OWIN's GetExternalLoginInfoAsync Always Returns null

Question

I've created a new MVC5 Web Application, and when I try to login with Google or Facebook, the ExternalLoginCallback Action in the AccountController is called, but GetExternalLoginInfoAsync() always returns null:

var loginInfo = await AuthenticationManager.GetExternalLoginInfoAsync();
if (loginInfo == null)
{
    return RedirectToAction("Login");
}

Because it's always null, it just redirects back to the login page and the process starts over. How can I fix this?

Solution 1

To get OWIN Google login to work properly on a standard Visual Studio 2013, ASP.Net MVC5 site, I had to:

1. Setup a Google OpenId account at https://console.developers.google.com/project

2. Set the callback URL there to blah/signin-google.
   Important notes on things you don't need to do:

   • You don't need to use HTTPS for Google to redirect back; you can even redirect back to plain http://localhost, no problem.

   • You don't need to setup anything for the redirect URL - no routes, Controller Actions or special permissions in Web.Config. The redirect URL is always /signin-google and OWIN handles this behind the scenes for you.

As an example, if your site was me.com, you might have these 3 callback URLs in the Google Developer Console:

http://localhost:53859/signin-google
http://test.me.com/signin-google
https://me.com/signin-google

The first one including whatever port number VS gave you for your project.

3. Enable the Google+ API. This is one hidden b**** of a gotcha and is the root cause of the problem in the question here - if you don't do this, it's easy to miss that the Request to /account/ExternalLoginCallback includes &error=access_denied, and that's because Google said no to a permissions request OWIN made for the user's Google+ basic profile. I can't tell whose fault this is, Google's or Microsoft's.

To enable the Google+ API in the Developers Console, click APIs on the left, hunt for Google+, click that and hit Enable. Yes you really do need to do that. You're hosed if you don't do that.

4. Add the ClientId and ClientSecret Google gave you in the Developers Console to Startup.Auth, but improve the code in the process to explicitly use OAuth2, and explicitly ask for the user's email address:

   var google = new GoogleOAuth2AuthenticationOptions()
   {
       ClientId = "123abc.apps.googleusercontent.com",
       ClientSecret = "456xyz",
       Provider = new GoogleOAuth2AuthenticationProvider()
   };
   google.Scope.Add("email");
   app.UseGoogleAuthentication(google);
   

That's it. That finally got it working.

Just want to reiterate one more time, there are a LOT of answers about this and issues like it where OWIN/Google isn't working, and nearly all of them are wrong for the current VS2013/MVC5/OWIN template.
You don't need to modify Web.Config at all.
You don't need to create any special Routes whatsoever.
You should not attempt to point /signin-google to a different place, or use a different callback URL, and you definitely shouldn't attempt to tie it directly to /account/externallogincallback or externalloginconfirmation, because those are both separate from /signin-google and necessary steps in the OWIN/Google process.

Solution 2

OK, I found out why it's null. You have to enable Google + API in the Google console. Also make sure the secret key is not concatenated with a space at the end after you paste it to your code. Why can't they return a normal error? I don't know.

Solution 3

It seems that Nuget package Microsoft.Owin.Security.Facebook version 3.0.1 no longer works with Facebook Login.

Update this package to the pre-release 3.1.0 version, you can use the following:

Install-Package Microsoft.Owin.Security.Facebook -Pre

Solution 4

As others correctly mentioned, most of the time that's because you do not have permission to the Google+ API so here is how to get permission for a project in Google API Manager to Google+ API

Step 1. Select You Project from the top combobox and go to Dashboard > Enable API

Step 2: Search for Google plus and select it

Step 3: Enable it!

if you return to dashboard for that project you can see the list of enabled API's for that project at the bottom

Solution 5

I got it to work by simply updating all the nugget package in the application and it worked.

View more solutions

Comments

[James Mauldin]

This immediately solved the problem. Good find, thanks.

[James Mauldin]

Now that I look carefully, I see that this step is clearly indicated in the instructions on asp.net.

[Ronen Festinger]

Yes, but I thought it's not obligatory. Anyway the connection between that and the error that is shown is not clear.

[Papa Burgundy]

Yes, I've seen all kinds of crazy answers but this is the correct one for me.

[roboto1986]

Number three did it for me. Sadly, I knew this to be the problem in the past but had forgotten it... and yes, totally agree this is a b**** . Many thanks for the list.

[Pawel Cioch]

Thank you, Thank you, Thank You! Worked, yes ENABLE Google+ API, it worked even without "code improvement". Great detailed answer!

[Patrick]

Same here but the problem returned after a while (days). It worked fine for some time then all of a sudden it just stops and a refresh of the app pool solves it again. Very weird.

[Patrick]

This solved the issue for me. Hopefully it will keep working now. stackoverflow.com/a/20948631/155758

[Giovanni Galbo]

If I could upvote you 1000 times, I would. Thank you!

[tutiplain]

Doesn't work for me. It is actually impossible to create an appID and appSecret without enabling Google+ API. I have enabled it and was able to create the secret and id, but I am still being redirected back to the login page.

[Chris Moschini]

@tutiplain Reread the answer; you need to enable the Google+ API.

[tutiplain]

I have it enabled, but it still doesn't work. I am considering manually doing the Oauth flow, since this seems to be a bug in either Owin or the project templates in Visual Studio.

[Ashish Shukla]

I have enable the Google + API and following the same steps, but it's not working for me. I am using Visual Studio 2015 MVC 5 Template. I am getting the user info null.

[Kris]

You sir, are a god!

[Chris Searles]

Just came across this out of nowhere today as well and updating to the RC of 3.1.0 worked for me too.

[Luke]

Glad to have helped :)

[Richard]

Crikey, hope they fix this soon spent all night reconfiguring URLs trying to work out what I'd inadvertently changed since it was working last time I was playing around. Your suggestion worked. Still no updated version later that 3.0.1 to install according to NuGet

[torylor]

^^ what Richard said

[Dan Cook]

After trying pretty much everything on stack overflow and wasting about 3 hours, this was the final solution for me. Thanks :)

[Luke]

It looks like it's no longer a pre-release, it's a real version now

[johnnyRose]

Upgrading to 3.1 fixed my problem. Thanks for saving me many painful hours debugging this!

[Martin]

Enable Google+ API... That's what I was missing. Thanks!

[Jeff D]

I can't understand why Google has not mentioned this in their documentation to enable google plus api to use "sign in with google button".. really bad.. if this post wasn't there I would have been lost for days..

[Samuel Moshie]

Thanks this solved my problem Microsoft need to look at this bug

[christiaantober]

This worked for me too, after trying everything else mentioned here. I updated the OWIN packages from v4.0.0 to v4.0.1 and then it started working.