I try to get the reviews for an enterprise to show it on their website.

But I can’t connect, I have all ready uri redirect mismatch.

I am developing with ASP.NET MVC 5, C#, I tried app.authgoogleAuth for OAuth2, but it doesn’t work.

In startup.auth.cs, I have:

app.UseGoogleAuthentication(new GoogleOAuth2AuthenticationOptions()
{
      ClientId = "xxxMyClientID",
      ClientSecret = "xxxMyclientsecret"
});

In my controller:

private readonly IDataStore dataStore = new FileDataStore(GoogleWebAuthorizationBroker.Folder);

private async Task<UserCredential> GetCredentialForApiAsync()
{
    var initializer = new GoogleAuthorizationCodeFlow.Initializer
    {
        ClientSecrets = new ClientSecrets
        {
                 ClientId = "xxxMyClientId",
                 ClientSecret = "xxxMyClientSecret",
        },
        Scopes = MyRequestedScopes.Scopes,
    };

    var flow = new GoogleAuthorizationCodeFlow(initializer);

    var identity = await HttpContext.GetOwinContext().Authentication.GetExternalIdentityAsync(
        DefaultAuthenticationTypes.ApplicationCookie); 
            
   var userId = identity.FindFirstValue(MyClaimTypes.GoogleUserId);

   var token = await dataStore.GetAsync<TokenResponse>(userId);
   return new UserCredential(flow, userId, token);
}

But identity is always null.

Can anyone help me?

Thanks