Prevent browsers from caching messages/scripts

Implement cache control on `messages/scripts` endpoint and script tag to
prevent browsers from caching the resuts and preventing audio playback.

CHANGELOG.markdown

@@ -8,6 +8,7 @@
 - Fix notification settings save when altering settings as a tenant. (Thanks @AsaadQ)
 - Removing obsolete update check.
 - Numerous small fixes, code style updates, and docblock fixes of issues found during static analysis.
+- Implement cache control on `messages/scripts` endpoint and script tag to prevent caching.
 
 
 ## OpenVBX 1.2.17

OpenVBX/controllers/messages/inbox.php

@@ -164,8 +164,12 @@ public function scripts($group = false)
 			$messageIdsJson = '{}';
 		}
 
-		/* TODO: implement JS responding */
 		header('content-type: text/javascript');
+		header('Expires: Fri, 22 Mar 1974 06:30:00 GMT');
+		header('Last-Modified: ' . gmdate( 'D, d M Y H:i:s') . ' GMT');
+		header('Cache-Control: no-store, no-cache, must-revalidate');
+		header('Cache-Control: post-check=0, pre-check=0', false);
+		header('Pragma: no-cache');
 		echo "$(document).ready(function(){ Message.Player.messageIdsToRecordingURLs = ".
 				$messageIdsJson."; });";
 	}
@@ -196,8 +200,10 @@ private function inbox($group = false)
 			return;
 		}
 
+		$ts = time();
+
 		$this->template->add_js('messages/scripts'.($group? '/'.$group : '').'?'.
-									http_build_query(compact('max', 'offset')), 'dynamic');
+									http_build_query(compact('max', 'offset', 'ts')), 'dynamic');
 
 		$data['group'] = $group;
 		$total_items = 0;