Code generator error: There is no entity type on DbContext
<p>I want to create simple ASP.NET Core App. But when I'm trying to generate API Controller for my model I'm getting following error: 
(Screen shots presents code for model class and db context, below is code for EntityBase class)</p>

<p><a href="https://i.stack.imgur.com/ibb9t.png" rel="noreferrer"><img src="https://i.stack.imgur.com/ibb9t.png" alt="Setting up code scaffolding properties"></a></p>

<p><a href="https://i.stack.imgur.com/9ix1p.png" rel="noreferrer"><img src="https://i.stack.imgur.com/9ix1p.png" alt="Error"></a></p>

<pre><code>public abstract class EntityBase
{
    [Key]
    public int Id { get; set; }
    public DateTime Modified { get; set; }
    public DateTime Created { get; set; }

    public EntityBase()
    {
        Created = DateTime.Now;
        Modified = Created;
    }
}
</code></pre>