Added -rewriteRequestURL:withMethod:headers: hook

GCDWebServer/Core/GCDWebServerConnection.h

@@ -117,6 +117,14 @@
  */
 - (void)didWriteBytes:(const void*)bytes length:(NSUInteger)length;
 
+/**
+ *  This method is called after the HTTP headers have been received to
+ *  allow replacing the request URL by another one.
+ *
+ *  The default implementation returns the original URL.
+ */
+- (NSURL*)rewriteRequestURL:(NSURL*)url withMethod:(NSString*)method headers:(NSDictionary*)headers;
+
 /**
  *  Assuming a valid HTTP request was received, this method is called before
  *  the request is processed.

GCDWebServer/Core/GCDWebServerConnection.m

@@ -522,11 +522,15 @@ static inline NSUInteger _ScanHexNumber(const void* bytes, NSUInteger size) {
         requestMethod = @"GET";
         _virtualHEAD = YES;
       }
+      NSDictionary* requestHeaders = ARC_BRIDGE_RELEASE(CFHTTPMessageCopyAllHeaderFields(_requestMessage));  // Header names are case-insensitive but CFHTTPMessageCopyAllHeaderFields() will standardize the common ones
       NSURL* requestURL = ARC_BRIDGE_RELEASE(CFHTTPMessageCopyRequestURL(_requestMessage));
+      if (requestURL) {
+        requestURL = [self rewriteRequestURL:requestURL withMethod:requestMethod headers:requestHeaders];
+        DCHECK(requestURL);
+      }
       NSString* requestPath = requestURL ? GCDWebServerUnescapeURLString(ARC_BRIDGE_RELEASE(CFURLCopyPath((CFURLRef)requestURL))) : nil;  // Don't use -[NSURL path] which strips the ending slash
       NSString* queryString = requestURL ? ARC_BRIDGE_RELEASE(CFURLCopyQueryString((CFURLRef)requestURL, NULL)) : nil;  // Don't use -[NSURL query] to make sure query is not unescaped;
       NSDictionary* requestQuery = queryString ? GCDWebServerParseURLEncodedForm(queryString) : @{};
-      NSDictionary* requestHeaders = ARC_BRIDGE_RELEASE(CFHTTPMessageCopyAllHeaderFields(_requestMessage));  // Header names are case-insensitive but CFHTTPMessageCopyAllHeaderFields() will standardize the common ones
       if (requestMethod && requestURL && requestHeaders && requestPath && requestQuery) {
         for (_handler in _server.handlers) {
           _request = ARC_RETAIN(_handler.matchBlock(requestMethod, requestURL, requestHeaders, requestPath, requestQuery));
@@ -713,6 +717,10 @@ static NSString* _StringFromAddressData(NSData* data) {
 #endif
 }
 
+- (NSURL*)rewriteRequestURL:(NSURL*)url withMethod:(NSString*)method headers:(NSDictionary*)headers {
+  return url;
+}
+
 // https://tools.ietf.org/html/rfc2617
 - (GCDWebServerResponse*)preflightRequest:(GCDWebServerRequest*)request {
   LOG_DEBUG(@"Connection on socket %i preflighting request \"%@ %@\" with %lu bytes body", _socket, _virtualHEAD ? @"HEAD" : _request.method, _request.path, (unsigned long)_bytesRead);