WebServer: Ensure directory listing URLs end with a slash

We will now send a redirect (301) if a directory listing is requested and the
request URL doesn't end with a slash character. This makes relative file URLs
that we generate in directory listings actually work as expected.

Servers/WebServer/Client.cpp

@@ -91,6 +91,17 @@ void Client::handle_request(ByteBuffer raw_request)
  auto real_path = path_builder.to_string();
 
  if (Core::File::is_directory(real_path)) {
+
+ if (!request.resource().ends_with("/")) {
+ StringBuilder red;
+
+ red.append(requested_path);
+ red.append("/");
+
+ send_redirect(red.to_string(), request);
+ return;
+ }
+
  StringBuilder index_html_path_builder;
  index_html_path_builder.append(real_path);
  index_html_path_builder.append("/index.html");
@@ -125,6 +136,20 @@ void Client::send_response(StringView response, const Core::HttpRequest& request
  log_response(200, request);
 }
 
+void Client::send_redirect(StringView redirect_path, const Core::HttpRequest& request)
+{
+ StringBuilder builder;
+ builder.append("HTTP/1.0 301 Moved Permanently\r\n");
+ builder.append("Location: ");
+ builder.append(redirect_path);
+ builder.append("\r\n");
+ builder.append("\r\n");
+
+ m_socket->write(builder.to_string());
+
+ log_response(301, request);
+}
+
 void Client::handle_directory_listing(const String& requested_path, const String& real_path, const Core::HttpRequest& request)
 {
  StringBuilder builder;

Servers/WebServer/Client.h

@@ -45,6 +45,7 @@ class Client final : public Core::Object {
 
  void handle_request(ByteBuffer);
  void send_response(StringView, const Core::HttpRequest&);
+ void send_redirect(StringView redirect, const Core::HttpRequest& request);
  void send_error_response(unsigned code, const StringView& message, const Core::HttpRequest&);
  void die();
  void log_response(unsigned code, const Core::HttpRequest&);