Как получить доступ к строке подключения к БД в DAL из уровня представления

У меня есть проект веб-API .net core 2.0 с несколькими уровнями, то есть Presentation, BLL, DAL ... У меня есть строка подключения в файле appsettings.json, который присутствует на уровне презентации. Мой DAL отвечает за получение данных из БД на основе этой строки подключения. Как мне прочитать этот файл json или передать строку подключения в DAL.
P.S. Уровень представления зависит от BLL, а BLL зависит от DAL.

appsettings.json

{
  "Logging": {
    "IncludeScopes": false,
    "Debug": {
      "LogLevel": {
        "Default": "Warning"
      }
    },
    "Console": {
      "LogLevel": {
        "Default": "Warning"
      }
    }
  },
  "ConnectionStrings": {
    "MsSqlConnectionString": "Data Source=myServerName;Database=myDB;User Id=myUserID;Password=myPWd;"
  }
}

DAL класс

protected readonly string _connectionString;
protected IDbConnection _connection { get { return new SqlConnection(_connectionString); } }

public BaseDal()
{
    _connectionString = "<<How to get connectionstring from appsetting.json>>";
}

ЧайлдДАЛ

public class MyDAL : BaseDal, IMyDAL
{
    ILogger _log;
    public MyDAL(ILoggerFactory loggerFactory)
    {
        _log = loggerFactory.CreateLogger("ChildDAL");
    }
    public async Task<IEnumerable<MyModel>> MyMethod(Dto criteria)
    {
        StringBuilder sql = new StringBuilder();

        sql.Append("SELECT * FROM table");
        string query = sql.ToString();
        // custom mapping
        DapperCustomMapping<MyModel>();

        using (IDbConnection dbConnection = _connection)
        {
            return await dbConnection.QueryAsync<MyModel>(query);
        }
    }
}

Startup.cs

public class Startup
{
    public IConfigurationRoot Configuration { get; }

    public Startup(IHostingEnvironment env)
    {
        var builder = new ConfigurationBuilder()
             .SetBasePath(env.ContentRootPath)
             .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);

        Configuration = builder.Build();
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
    {
        //loggerFactory.AddConsole(Configuration.GetSection("Logging"));
        loggerFactory.AddDebug();
        loggerFactory.AddLog4Net();

        app.UseErrorWrappingMiddleware();
        app.UseStatusCodePagesWithReExecute("/error/{0}");
        app.UseExceptionHandler("/error/500");

        // CORS: UseCors with CorsPolicyBuilder.
        app.UseCors("AllowSpecificOrigin");

        // MVC
        app.UseMvc();

        // Enable middleware to serve generated Swagger as a JSON endpoint.
        app.UseSwagger();

        //Enable middleware to serve swagger - ui
        app.UseSwaggerUI(c =>
        {
            c.SwaggerEndpoint("../swagger/v1/swagger.json", "My API v1");
        });
    }

    // This method gets called by the runtime. Use this method to add services to the container.
    // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
    public IServiceProvider ConfigureServices(IServiceCollection services)
    {
        // Read appsettings.json to get allowed origins
        var whiteList = new List<string>();
        var myArraySection = Configuration["AllowedOrigin"];
        if (!String.IsNullOrEmpty(myArraySection))
        {
            foreach (var d in myArraySection.Split(','))
            {
                whiteList.Add(d.Trim());
            }
        }

        // CORS
        services.AddCors(options =>
        {
            options.AddPolicy("AllowSpecificOrigin",
                policy => policy.WithOrigins(whiteList.ToArray()));
        });

        // Add framework services.
        services.AddMvc(options =>
        {
            // install global fitler on all controllers and actions.
            options.Filters.Add(new CorsAuthorizationFilterFactory("AllowSpecificOrigin"));
            options.Filters.Add(new ValidateModelAttribute());
        })
        // tell how to find the fluent validations
        .AddFluentValidation(fv => fv.RegisterValidatorsFromAssemblyContaining<ContactQueryDtoValidator>());

        // Register the Swagger generator
        services.AddSwaggerGen(c =>
        {
            c.SwaggerDoc("v1", new Info { Title = "API", Version = "v1" });
        });

        return ConfigureIoC(services);
    }

    public IServiceProvider ConfigureIoC(IServiceCollection services)
    {
        var container = new Container();
        container.Configure(config =>
        {
            config.Scan(_ =>
            {
                _.AssemblyContainingType(typeof(Startup)); // web api
                _.AssemblyContainingType(typeof(HelloBLL)); // Unused BLL
                _.AssemblyContainingType(typeof(HelloDAL)); // Unused DAL
                _.TheCallingAssembly();
                _.WithDefaultConventions();

            });

            config.Populate(services);
        });
        return container.GetInstance<IServiceProvider>();
    }
}