diff --git a/src/main/java/cokr/xit/foundation/web/WebClient.java b/src/main/java/cokr/xit/foundation/web/WebClient.java
index 236fc7c..71bd3ba 100644
--- a/src/main/java/cokr/xit/foundation/web/WebClient.java
+++ b/src/main/java/cokr/xit/foundation/web/WebClient.java
@@ -4,6 +4,7 @@ import java.io.FileOutputStream;
 import java.io.InputStream;
 import java.math.BigInteger;
 import java.net.Authenticator;
+import java.net.CookieHandler;
 import java.net.ProxySelector;
 import java.net.URI;
 import java.net.URLEncoder;
@@ -83,12 +84,21 @@ import cokr.xit.foundation.data.JSON;
  * @author mjkhan
  */
 public class WebClient {
+	/**http 통신의 로그를 출력하도록 설정한다.
+	 */
+	public static void debug() {
+		System.setProperty("jdk.httpclient.HttpClient.log", "errors,requests,headers,frames[:control:data:window:all],content,ssl,trace,channel,all");
+	}
+
 	private HttpClient.Version version = HttpClient.Version.HTTP_2;
 	private Duration timeout = Duration.ofSeconds(30);
 	private Authenticator authenticator;
 	private SSLContext sslContext;
 	private ProxySelector proxy;
 
+	private Charset charset;
+	private CookieHandler cookieHandler;
+
 	private HttpClient.Redirect followRedirects = HttpClient.Redirect.NORMAL;
 
 	/**http 프로토콜의 버젼을 설정한다. 디폴트는 HTTP/2
@@ -136,6 +146,24 @@ public class WebClient {
 		return this;
 	}
 
+	public Charset charset() {
+		return Assert.ifEmpty(charset, StandardCharsets.UTF_8);
+	}
+
+	/**문자셋을 설정한다. 디폴트는 UTF-8.
+	 * @param charset 요청의 문자셋
+	 * @return 현재 WebClient
+	 */
+	public WebClient charset(String charset) {
+		this.charset = Charset.forName(charset);
+		return this;
+	}
+
+	public WebClient cookieHandler(CookieHandler cookieHandler) {
+		this.cookieHandler = cookieHandler;
+		return this;
+	}
+
 	/**서버의 응답이 redirect일 경우 대응 방법을 설정한다. 디폴트는 HttpClient.Redirect.NORMAL.
 	 * @param redirect redirect 응답에 대한 대응 방법
 	 * @return 현재 WebClient
@@ -145,20 +173,28 @@ public class WebClient {
 		return this;
 	}
 
+	private HttpClient client;
+
 	private HttpClient client() {
-		HttpClient.Builder builder = HttpClient.newBuilder()
-			.version(version)
-			.connectTimeout(timeout)
-			.followRedirects(followRedirects);
-
-		if (authenticator != null)
-			builder.authenticator(authenticator);
-		if (sslContext != null)
-			builder.sslContext(sslContext);
-		if (proxy != null)
-			builder.proxy(proxy);
-
-		return builder.build();
+		if (client == null) {
+			HttpClient.Builder builder = HttpClient.newBuilder()
+				.version(version)
+				.connectTimeout(timeout)
+				.followRedirects(followRedirects);
+
+			if (authenticator != null)
+				builder.authenticator(authenticator);
+			if (sslContext != null)
+				builder.sslContext(sslContext);
+			if (proxy != null)
+				builder.proxy(proxy);
+
+			if (cookieHandler != null)
+				builder.cookieHandler(cookieHandler);
+
+			client = builder.build();
+		}
+		return client;
 	}
 
 	/**"GET" 방식의 요청을 전송한다.
@@ -169,6 +205,7 @@ public class WebClient {
 	@SuppressWarnings("unchecked")
 	public <T> HttpResponse<T> get(Consumer<Request> configurer) {
 		Request req = new Request();
+		req.charset = charset();
 		configurer.accept(req);
 		HttpRequest hreq = req.get();
 
@@ -190,12 +227,12 @@ public class WebClient {
 		log().debug("Sending request:\n{} {}", hreq.method(), hreq.uri());
 		if (!async) {
 			HttpResponse<T> resp = client().send(hreq, bodyHandler);
-			log().debug("Received response");
+			log().debug("{} response received", resp.statusCode());
 			return resp;
 		} else {
 			CompletableFuture<HttpResponse<T>> future = client().sendAsync(hreq, bodyHandler);
 			future.thenApply(resp -> {
-				log().debug("Received response");
+				log().debug("{} response received", resp.statusCode());
 				respHandler.accept(resp);
 				return resp;
 			});
@@ -215,6 +252,7 @@ public class WebClient {
 	@SuppressWarnings("unchecked")
 	public <T> HttpResponse<T> post(Consumer<Request> configurer) {
 		Request req = new Request();
+		req.charset = charset();
 		configurer.accept(req);
 		HttpRequest hreq = req.post();
 
@@ -247,6 +285,14 @@ public class WebClient {
 		}
 	}
 
+	public String toString(InputStream inputStream) {
+		try {
+			return new String(inputStream.readAllBytes(), charset());
+		} catch (Exception e) {
+			throw Assert.runtimeException(e);
+		}
+	}
+
 	/**전송할 http 요청의 설정.
 	 * <p>Request로 다음 항목들을 설정한다.
 	 * <ul><li>{@link #uri(String) uri}: 대상 서버의 uri</li>
@@ -295,7 +341,7 @@ public class WebClient {
 		private boolean
 			async,
 			download;
-		private Charset charset = StandardCharsets.UTF_8;
+		private Charset charset;
 		private LinkedHashMap<String, String> headers;
 		private LinkedHashMap<String, Object> keyValues;
 
@@ -357,13 +403,14 @@ public class WebClient {
 			return this;
 		}
 
-		/**요청의 문자셋을 설정한다. 디폴트는 UTF-8.
-		 * @param charset 요청의 문자셋
+		/**캐시를 사용하지 않도록 헤더를 설정한다.
 		 * @return 현재 Request
 		 */
-		public Request charset(Charset charset) {
-			this.charset = charset;
-			return this;
+		public Request noCache() {
+			return
+				header("Cache-Control", "no-cache, no-store, must-revalidate")
+			   .header("Pragma", "no-cache")
+			   .header("Expires", "0");
 		}
 
 		/**요청이 비동기인지 설정한다. 디폴트는 false(동기).