Radicade/Server/DB/RecDBContextFactory.cs

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;

namespace RadicadeServer.DB
{
	public class RecDBContextFactory : IDesignTimeDbContextFactory<RecDBContext>
	{
		public RecDBContext CreateDbContext(string[] args)
		{
			var config = new ConfigurationBuilder()
				.SetBasePath(Directory.GetCurrentDirectory())
				.AddJsonFile("appsettings.json", optional: true)
				.AddJsonFile("appsettings.Development.json", optional: true)
				.AddEnvironmentVariables()
				.Build();

			var connectionString = config.GetConnectionString("DefaultConnection");
			if (string.IsNullOrWhiteSpace(connectionString))
				throw new InvalidOperationException("Missing ConnectionStrings:DefaultConnection for design-time context creation.");

			var options = new DbContextOptionsBuilder<RecDBContext>()
				.UseSqlServer(connectionString)
				.Options;

			return new RecDBContext(options);
		}
	}
}