How to configure hangfire with ASP.NET to obtain connection string from config file?

问题

Please forgive me this probably stupid question, I am still not too familiar with the ASP.NET architecture in general.

I inherited a large project, and I intend to setup hangfire.io. I understand that I have to somehow initialize the DB context, but I do not want to hardcode it as suggested by the hangfire-docu.

My API\Global.asax.cs currently looks as follows, the interesting stuff begins after // Hangfire stuff:

using System.Web.Http;
using System.Web.Http.ExceptionHandling;
using System.Web.Mvc;
using System.Web.Optimization;
using System.Web.Routing;
using Hangfire;

namespace API
{
   public class WebApiApplication : System.Web.HttpApplication
   {
       protected void Application_Start()
       {
          log4net.Config.XmlConfigurator.Configure();
          GlobalConfiguration.Configuration.Services.Add(typeof(IExceptionLogger), new GlobalExceptionLogger());
          GlobalConfiguration.Configuration.Services.Replace(typeof(IExceptionHandler), new GlobalExceptionHandler());
          MvcHandler.DisableMvcResponseHeader = true;
          AreaRegistration.RegisterAllAreas();
          GlobalConfiguration.Configure(WebApiConfig.Register);
          FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
          RouteConfig.RegisterRoutes(RouteTable.Routes);
          MapperConfig.RegisterMapper();

          // Hangfire stuff  
          GlobalConfiguration.Configuration.UseSqlServerStorage("HardcodedContextString");
          RecurringJob.AddOrUpdate("some-id", () => Console.WriteLine("My hangfire test."), "*/2 * * * 1-5"); 
       }
   }
}

My database context myContext seems to defined inside API\connections.config which contains the following lines:

<?xml version="1.0"?>
  <connectionStrings>
    <add name="myContext" connectionString="Data Source=localhost\sqlexpress;Initial Catalog=myContext;Integrated Security=SSPI;" providerName="System.Data.SqlClient" />
  </connectionStrings>

What shall I put instead of HardcodedContextString to make ASP.NET read the connection string from the respective configuration file?

PS: Interestingly, both lines underneath // Hangfire stuff is underlined in red. What do I miss?

References

How do I set up 'connectionString' for a mySQL database for Hangfire?

回答1:

Make sure that Hangfire is actually installed (see also Hangfire Installation Guide). For Visual Studio Professional 2017, you can do the following:
1. Right-click on your project and click Manage NuGet Packages.
2. Select Packet source: nuget.org on the right, search for Hangfire using the search bar on the top left.
3. Select Hangfire and click Install. You might have to click on Accept when a popup-window appears.
Add using System.Configuration; in the header of Global.asax.cs. All following steps will happen within that file.
Define a variable which obtains the data base context definition from connections.config:

string connString = ConfigurationManager.ConnectionStrings["ConStringName"].ToString();

If you are using System.Web.Http like me, you have to replace all appearances of GlobalConfiguration.xxx with System.Web.Http.GlobalConfiguration.xxx. This is necessary to avoid a conflict since both packages have a (different) GlobalConfiguration property.
We also have to specify the full namespace for Hangfire. We will also use connString now: Instead of GlobalConfiguration.Configuration.UseSqlServerStorage("HardcodedContextString"); we have to write

Hangfire.GlobalConfiguration.Configuration.UseSqlServerStorage(connString);

Everything should now compile without errors.

PS: From https://stackoverflow.com/a/6134384/1236044 I learned how to obtain the connection string from the config file-- thanks @jbl for pointing me to that. JBL also gave me the hint about the name space conflict.

来源：https://stackoverflow.com/questions/59736118/how-to-configure-hangfire-with-asp-net-to-obtain-connection-string-from-config-f

标签

ASP.NET

dbcontext

hangfire