.NET Core - Entity Framework Core - IDesignTimeDbContextFactory Implementation

CampContextFactory.cs

public class CampContextFactory : IDesignTimeDbContextFactory
{
   public CampContext CreateDbContext(string[] args)
   {
      var configuration = new ConfigurationBuilder()
           .SetBasePath(Directory.GetCurrentDirectory())
           .AddJsonFile("appsettings.json")
           .Build();

      var dbContextBuilder = new DbContextOptionsBuilder();

      var connectionString = configuration
                  .GetConnectionString("SqlConnectionString");

      dbContextBuilder.UseSqlServer(connectionString);

      return new CampContext(dbContextBuilder.Options);
    }
}