DotNetOpenAuth.OAuth2.WebServerClient.ProcessUserAuthorization C# (CSharp) Method

		public IAuthorizationState ProcessUserAuthorization(HttpRequestBase request = null) {
			Requires.ValidState(!string.IsNullOrEmpty(this.ClientIdentifier), OAuth2Strings.RequiredPropertyNotYetPreset, "ClientIdentifier");
			Requires.ValidState(!string.IsNullOrEmpty(this.ClientSecret), OAuth2Strings.RequiredPropertyNotYetPreset, "ClientSecret");

			if (request == null) {
				request = this.Channel.GetRequestFromContext();
			}

			IMessageWithClientState response;
			if (this.Channel.TryReadFromRequest<IMessageWithClientState>(request, out response)) {
				Uri callback = MessagingUtilities.StripMessagePartsFromQueryString(request.GetPublicFacingUrl(), this.Channel.MessageDescriptions.Get(response));
				IAuthorizationState authorizationState;
				if (this.AuthorizationTracker != null) {
					authorizationState = this.AuthorizationTracker.GetAuthorizationState(callback, response.ClientState);
					ErrorUtilities.VerifyProtocol(authorizationState != null, OAuth2Strings.AuthorizationResponseUnexpectedMismatch);
				} else {
					var context = this.Channel.GetHttpContext();
					if (context.Session != null) {
						ErrorUtilities.VerifyProtocol(string.Equals(response.ClientState, context.Session.SessionID, StringComparison.Ordinal), OAuth2Strings.AuthorizationResponseUnexpectedMismatch);
					} else {
						Logger.OAuth.WarnFormat("No request context discovered, so no client state parameter could be checked to mitigate XSRF attacks.");
					}

					authorizationState = new AuthorizationState { Callback = callback };
				}
				var success = response as EndUserAuthorizationSuccessAuthCodeResponse;
				var failure = response as EndUserAuthorizationFailedResponse;
				ErrorUtilities.VerifyProtocol(success != null || failure != null, MessagingStrings.UnexpectedMessageReceivedOfMany);
				if (success != null) {
					this.UpdateAuthorizationWithResponse(authorizationState, success);
				} else { // failure
					Logger.OAuth.Info("User refused to grant the requested authorization at the Authorization Server.");
					authorizationState.Delete();
				}

				return authorizationState;
			}

			return null;
		}
	}

 public virtual IAuthorizationState ProcessUserAuthorization(
     WebServerClient authClient, AuthorizationServerDescription authServer, IServiceBase authService)
 {
     return HostContext.Config.StripApplicationVirtualPath
         ? authClient.ProcessUserAuthorization(authService.Request.ToHttpRequestBase())
         : authClient.ProcessUserAuthorization();
 }