Connect the XPO Profiler to an ASP.NET Core Application

• Apr 02, 2019
• 3 minutes to read

This topic describes how to profile ASP.NET Core applications using the XPO Profiler.

Connection Setup

• Create the following controller:

  using DevExpress.Xpo.Logger; 
  using Microsoft.AspNetCore.Mvc; 
  // ...
  public class XpoLoggerController : Controller { 
      readonly static LoggerBase logger = new LoggerBase(50000); 
      static XpoLoggerController() { 
          LogManager.SetTransport(logger); 
      } 
      [HttpGet] 
      public LogMessage[] GetCompleteLog() { 
          return logger.GetCompleteLog(); 
      } 
      [HttpGet] 
      public LogMessage GetMessage() { 
          return logger.GetMessage(); 
      } 
      [HttpGet] 
      public LogMessage[] GetMessages(int messagesAmount) { 
          return logger.GetMessages(messagesAmount); 
      }
  }
  

• Run the XPO Profiler. Click File | New. In the New Host dialog, supply the following parameters:

  Parameter	Value
  Binding type	Select “WebApi” in the drop-down list.
  Server name	Specify the hostname. The HTTP protocol is used by default. To use HTTPS, add the protocol prefix to the hostname (for example, “https://myserver”).
  Port	Specify the web site’s port number.
  Path	Specify the path to the controller (demonstrated in the first step) that corresponds to the web application (for example, “XpoLogger”).

  

• Click Test to test the connection.

Authentication Setup

XPO Profiler supports the following authentication types when using WebAPI binding:

Authentication Type	Description	Authentication Dialog
Anonymous	Your web application should provide a anonymous access to the controller demonstrated in the Connection Setup section.	None
Basic	XPO profiler displays the Authentication dialog where you can specify the login and password.
Token-Based	XPO profiler displays the Authentication dialog where you can specify the authentication token. Your web application should implement a custom authentication handler (see the section below for details).

Token-Based Authentication

• Implement the following XpoProfilerTokenHandler authentication handler:

  using Microsoft.AspNetCore.Authentication;
  // ...
  class XpoProfilerTokenHandler : AuthenticationHandler<AuthenticationSchemeOptions>, IAuthenticationHandler {
      const string ValidToken = "xpoxpo";
      public const string AuthScheme = "XpoProfilerToken";
      public XpoProfilerTokenHandler(IOptionsMonitor<AuthenticationSchemeOptions> options,
      ILoggerFactory logger, UrlEncoder encoder, ISystemClock clock) : base(options, logger, encoder, clock) { }
      protected override Task<AuthenticateResult> HandleAuthenticateAsync() {
          return Task.Run(() => {
              string header = Context.Request.Headers["Authorization"].FirstOrDefault(h => h.StartsWith(AuthScheme));
              if(header != null) {
                  string token = header.Substring(AuthScheme.Length + 1);
                  if(token == ValidToken) {
                      var principal = new ClaimsPrincipal(new ClaimsIdentity(null, AuthScheme));
                      return AuthenticateResult.Success(new AuthenticationTicket(principal, AuthScheme));
                  }
              }
              return AuthenticateResult.NoResult();
          });
      }
  }
  

  Important

  The XpoProfilerTokenHandler.ValidToken constant value (“xpoxpo“ in this example) is a token that you should specify in the XPO Profiler’s Authentication dialog to connect to your web application. Replace “xpoxpo“ with a custom secret token string for security purposes.

• Register your custom authentication handler in the Startup.ConfigureServices method declared in the Startup.cs file.

  public void ConfigureServices(IServiceCollection services) {
      services
          .AddAuthentication( /*your default authentication_scheme*/)
          .AddScheme<AuthenticationSchemeOptions, XpoProfilerTokenHandler>(XpoProfilerTokenHandler.AuthScheme, null);
  }
  

• Apply the Authorize attribute to your XpoLoggerController class (demonstrated in the Connection Setup section).

  using Microsoft.AspNetCore.Authorization;
  // ...
  [Authorize(AuthenticationSchemes = XpoProfilerTokenHandler.AuthScheme)]
  public class XpoLoggerController : Controller {
      // ...
  }