[C#/ASP.NET MVC/.NETCORE] DelegatingHandler 클래스 : 헤더 검증 핸들러 만들기

■ DelegatingHandler 클래스를 사용해 헤더 검증 핸들러를 만드는 방법을 보여준다.

▶ ValidateHeaderHandler.cs


using System.Net;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;

namespace TestProject
{
    /// <summary>
    /// 헤더 검증 핸들러
    /// </summary>
    public class ValidateHeaderHandler : DelegatingHandler
    {
        //////////////////////////////////////////////////////////////////////////////////////////////////// Method
        ////////////////////////////////////////////////////////////////////////////////////////// Protected

        #region 송신하기 (비동기) - SendAsync(request, cancellationToken)

        /// <summary>
        /// 송신하기 (비동기)
        /// </summary>
        /// <param name="httpRequestMessage">HTTP 요청 메시지</param>
        /// <param name="cancellationToken">취소 토큰</param>
        /// <returns>HTTP 응답 메시지 태스크</returns>
        protected override async Task<HttpResponseMessage> SendAsync
        (
            HttpRequestMessage httpRequestMessage,
            CancellationToken  cancellationToken
        )
        {
            if(!httpRequestMessage.Headers.Contains("X-API-KEY"))
            {
                return new HttpResponseMessage(HttpStatusCode.BadRequest)
                {
                    Content = new StringContent("You must supply an API key header called X-API-KEY")
                };
            }

            return await base.SendAsync(httpRequestMessage, cancellationToken);
        }

        #endregion
    }
}

using System.Net;

using System.Net.Http;

using System.Threading;

using System.Threading.Tasks;

namespace TestProject

{

/// <summary>

/// 헤더 검증 핸들러

/// </summary>

public class ValidateHeaderHandler : DelegatingHandler

{

//////////////////////////////////////////////////////////////////////////////////////////////////// Method

////////////////////////////////////////////////////////////////////////////////////////// Protected

#region 송신하기 (비동기) - SendAsync(request, cancellationToken)

/// <summary>

/// 송신하기 (비동기)

/// </summary>

/// <param name="httpRequestMessage">HTTP 요청 메시지</param>

/// <param name="cancellationToken">취소 토큰</param>

/// <returns>HTTP 응답 메시지 태스크</returns>

protected override async Task<HttpResponseMessage> SendAsync

(

HttpRequestMessage httpRequestMessage,

CancellationToken cancellationToken

)

{

if(!httpRequestMessage.Headers.Contains("X-API-KEY"))

{

return new HttpResponseMessage(HttpStatusCode.BadRequest)

{

Content = new StringContent("You must supply an API key header called X-API-KEY")

};

}

return await base.SendAsync(httpRequestMessage, cancellationToken);

}

#endregion

}