title: how to implement google login in .net core without an entityframework provider
body: <p>I am implementing Google login for my .net core site.</p>
  
  <p>In this code</p>
  
  <pre><code>var properties = signInManager.ConfigureExternalAuthenticationProperties("Google", redirectUrl);      
  return new ChallengeResult("Google", properties); 
  </code></pre>
  
  <p>I need a <code>signInManager</code> which is (by the code example) this:</p>
  
  <pre><code>private SignInManager&lt;AppUser&gt; signInManager;
  </code></pre>
  
  <p>I inject it via the constructor, and then I get this error:</p>
  
  <blockquote>
    <p>Unable to resolve service for type 'Microsoft.AspNetCore.Identity.SignInManager1[AppUser]' while attempting to activate 'AccountController'.</p>
  </blockquote>
  
  <p>Googling learnt that I should include this</p>
  
  <pre><code>services.AddIdentity&lt;AppUser, IdentityRole&gt;()
      .AddDefaultTokenProviders();`
  </code></pre>
  
  <p>But that gives me this error:</p>
  
  <blockquote>
    <p>Unable to resolve service for type 'Microsoft.AspNetCore.Identity.IUserStore1[AppUser]' while attempting to activate 'Microsoft.AspNetCore.Identity.AspNetUserManager1[AppUser]'.</p>
  </blockquote>
  
  <p>And at that moment, I get the advice to add this:</p>
  
  <pre><code>.AddEntityFrameworkStores&lt;ApplicationDbContext&gt;()
  </code></pre>
  
  <p>But then I'm lost, because why does the <code>SignInManager</code> need a <code>IUserStore</code>, and should I add a 
  <code>UserStore</code> and a <code>DBContext</code> and an <code>EntityFramework</code> store, when I will not be using that (for my Google login)?</p>
  
  <p>So the question is: can I also do my Google login without the Entityframework store?</p>