Fix response for HTTP HEAD method

Closes #19288.

src/base/http/connection.cpp

@@ -123,14 +123,30 @@ void Connection::read()
             {
                 const Environment env {m_socket->localAddress(), m_socket->localPort(), m_socket->peerAddress(), m_socket->peerPort()};
 
+                if (result.request.method == HEADER_REQUEST_METHOD_HEAD)
+                {
+                    Request getRequest = result.request;
+                    getRequest.method = HEADER_REQUEST_METHOD_GET;
+
+                    Response resp = m_requestHandler->processRequest(getRequest, env);
+
+                    resp.headers[HEADER_CONNECTION] = u"keep-alive"_s;
+                    resp.headers[HEADER_CONTENT_LENGTH] = QString::number(resp.content.length());
+                    resp.content.clear();
+
+                    sendResponse(resp);
+                }
+                else
+                {
                     Response resp = m_requestHandler->processRequest(result.request, env);
 
-                if (acceptsGzipEncoding(result.request.headers[u"accept-encoding"_s]))
+                    if (acceptsGzipEncoding(result.request.headers.value(u"accept-encoding"_s)))
                         resp.headers[HEADER_CONTENT_ENCODING] = u"gzip"_s;
-
                     resp.headers[HEADER_CONNECTION] = u"keep-alive"_s;
 
                     sendResponse(resp);
+                }
+
                 m_receivedData.remove(0, result.frameSize);
             }
             break;

src/base/http/responsegenerator.cpp

@@ -38,8 +38,9 @@ QByteArray Http::toByteArray(Response response)
 {
     compressContent(response);
 
-    response.headers[HEADER_CONTENT_LENGTH] = QString::number(response.content.length());
     response.headers[HEADER_DATE] = httpDate();
+    if (QString &value = response.headers[HEADER_CONTENT_LENGTH]; value.isEmpty())
+        value = QString::number(response.content.length());
 
     QByteArray buf;
     buf.reserve(1024 + response.content.length());
@@ -63,7 +64,7 @@ QByteArray Http::toByteArray(Response response)
     // the first empty line
     buf += CRLF;
 
-    // message body  // TODO: support HEAD request
+    // message body
     buf += response.content;
 
     return buf;