Propagate most headers on redirect, close AsyncHttpClient#824

Author: slandelle

src/main/java/com/ning/http/client/providers/netty/handler/Protocol.java

@@ -49,9 +49,6 @@
 
 import java.io.IOException;
 import java.util.HashSet;
-import java.util.List;
-import java.util.Locale;
-import java.util.Map;
 import java.util.Set;
 
 public abstract class Protocol {
@@ -75,16 +72,6 @@ public abstract class Protocol {
         REDIRECT_STATUSES.add(TEMPORARY_REDIRECT.getCode());
     }
 
-    public static final Set<String> PROPAGATED_ON_REDIRECT_HEADERS = new HashSet<>();
-    static {
-        PROPAGATED_ON_REDIRECT_HEADERS.add(ACCEPT.toLowerCase(Locale.US));
-        PROPAGATED_ON_REDIRECT_HEADERS.add(ACCEPT_CHARSET.toLowerCase(Locale.US));
-        PROPAGATED_ON_REDIRECT_HEADERS.add(ACCEPT_ENCODING.toLowerCase(Locale.US));
-        PROPAGATED_ON_REDIRECT_HEADERS.add(ACCEPT_LANGUAGE.toLowerCase(Locale.US));
-        PROPAGATED_ON_REDIRECT_HEADERS.add(REFERER.toLowerCase(Locale.US));
-        PROPAGATED_ON_REDIRECT_HEADERS.add(USER_AGENT.toLowerCase(Locale.US));
-    }
-
     public Protocol(ChannelManager channelManager, AsyncHttpClientConfig config, NettyAsyncHttpProviderConfig nettyConfig,
             NettyRequestSender requestSender) {
         this.channelManager = channelManager;
@@ -104,15 +91,14 @@ public Protocol(ChannelManager channelManager, AsyncHttpClientConfig config, Net
 
     public abstract void onClose(NettyResponseFuture<?> future);
 
-    private FluentCaseInsensitiveStringsMap propagatedHeaders(Request request) {
-        FluentCaseInsensitiveStringsMap redirectHeaders = new FluentCaseInsensitiveStringsMap();
-        for (Map.Entry<String, List<String>> headerEntry : request.getHeaders()) {
-            String headerName = headerEntry.getKey();
-            List<String> headerValues = headerEntry.getValue();
-            if (PROPAGATED_ON_REDIRECT_HEADERS.contains(headerName.toLowerCase(Locale.US)))
-                redirectHeaders.add(headerName, headerValues);
-        }
-        return redirectHeaders;
+    private FluentCaseInsensitiveStringsMap propagatedHeaders(Request request, boolean switchToGet) {
+        
+        FluentCaseInsensitiveStringsMap originalHeaders = request.getHeaders();
+        originalHeaders.remove(HOST);
+        originalHeaders.remove(CONTENT_LENGTH);
+        if (switchToGet)
+            originalHeaders.remove(CONTENT_TYPE);
+        return originalHeaders;
     }
 
     protected boolean exitAfterHandlingRedirect(//
@@ -139,7 +125,8 @@ protected boolean exitAfterHandlingRedirect(//
 
                     // if we are to strictly handle 302, we should keep the original method (which browsers don't)
                     // 303 must force GET
-                    if ((statusCode == FOUND.getCode() && !config.isStrict302Handling()) || statusCode == SEE_OTHER.getCode())
+                    boolean switchToGet = !request.getMethod().equals("GET") && (statusCode == 303 || (statusCode == 302 && !config.isStrict302Handling()));
+                    if (switchToGet)
                         requestBuilder.setMethod("GET");
 
                     // in case of a redirect from HTTP to HTTPS, future attributes might change
@@ -160,7 +147,7 @@ protected boolean exitAfterHandlingRedirect(//
                             requestBuilder.addOrReplaceCookie(c);
                     }
 
-                    requestBuilder.setHeaders(propagatedHeaders(future.getRequest()));
+                    requestBuilder.setHeaders(propagatedHeaders(future.getRequest(), switchToGet));
 
                     final Request nextRequest = requestBuilder.setUrl(newUrl).build();