Couven92.SeanAlford.ConsoleApp.csproj

<?xml version="1.0" encoding="utf-8"?>
<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>netcoreapp2.2</TargetFramework>
    <UserSecretsId>0864c15e-1de4-426a-97df-a43cb2700536</UserSecretsId>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="2.2.4" />
    <PackageReference Include="Microsoft.Extensions.Configuration.CommandLine" Version="2.2.0" />
    <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="2.2.0" />
    <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" Version="2.2.0" />
    <PackageReference Include="Microsoft.Extensions.Hosting" Version="2.2.0" />
    <PackageReference Include="Microsoft.Extensions.Logging.Configuration" Version="2.2.0" />
    <PackageReference Include="Microsoft.Extensions.Logging.Console" Version="2.2.0" />
  </ItemGroup>
</Project>

Program.cs

using System;
using System.CommandLine;
using System.CommandLine.Builder;
using System.CommandLine.Hosting;
using System.CommandLine.Invocation;
using System.Threading.Tasks;

using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

namespace Couven92.SeanAlford.ConsoleApp
{
    public static class Program
    {
        public static async Task Main(string[] args)
        {
            var host = new HostBuilder()
                .ConfigureHostConfiguration(config =>
                {
                    config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);
                    config.AddUserSecrets(typeof(Program).Assembly, optional: true);
                    config.AddCommandLine(args);
                })
                .ConfigureLogging((hostContext, logging) =>
                {
                    logging.AddConfiguration(hostContext.Configuration.GetSection(nameof(Microsoft.Extensions.Logging)));
                    logging.AddConsole();
                })
                .ConfigureServices((hostContext, services) =>
                {
                    services.AddDbContext<SqlServerContext>(db =>
                    {
                        var config = hostContext.Configuration;
                        string connectionString = config.GetConnectionString("db");
                        db.UseSqlServer(connectionString);
                    });
                    services.AddSingleton<ISystemNode, SystemNode>();
                    services.AddSingleton<Terminal>();
                })
                .UseConsoleLifetime().Build();
            using (host)
            {
                await host.StartAsync();

                var serviceProvider = host.Services;
                var terminal = serviceProvider.GetRequiredService<Terminal>();
                terminal.Run(args);

                await host.StopAsync();
            }
        }
    }

    internal class Terminal
    {
        public Terminal(ILogger<Terminal> logger, SqlServerContext dbContext, IApplicationLifetime lifetime)
        {
            Logger = logger;
            DbContext = dbContext;
            Lifetime = lifetime;
        }

        public ILogger<Terminal> Logger { get; }
        public SqlServerContext DbContext { get; }
        public IApplicationLifetime Lifetime { get; }

        internal void Run(string[] args)
        {
            Logger.LogCritical(new NotImplementedException(), null);
            
        }
    }

    internal interface ISystemNode
    {
    }

    internal class SystemNode : ISystemNode
    {
    }

    internal class SqlServerContext : DbContext
    {
        public SqlServerContext(DbContextOptions<SqlServerContext> options)
            : base(options) { }
    }
}