Add proper download started feedback

* this code adds a cookie when a special get parameter is set
* the content of this get parameter is used as value for the cookie
* the cookie expires after 20 seconds
* the JS code checks every 500 milliseconds for the cookie
  -> if the cookie is set the request returned and the download is started

1 files changed, 11 insertions, 0 deletions

diff --git a/apps/files/ajax/download.php b/apps/files/ajax/download.php
index e67635ab853..26bab8837b4 100644
--- a/apps/files/ajax/download.php
+++ b/apps/files/ajax/download.php
@@ -39,4 +39,15 @@ if (!is_array($files_list)) {
 	$files_list = array($files);
 }
 
+/**
+ * this sets a cookie to be able to recognize the start of the download
+ * the content must not be longer than 32 characters and must only contain
+ * alphanumeric characters
+ */
+if(isset($_GET['downloadStartSecret'])
+	&& !isset($_GET['downloadStartSecret'][32])
+	&& preg_match('!^[a-zA-Z0-9]+$!', $_GET['downloadStartSecret']) === 1) {
+	setcookie('ocDownloadStarted', $_GET['downloadStartSecret'], time() + 20, '/');
+}
+
 OC_Files::get($dir, $files_list, $_SERVER['REQUEST_METHOD'] == 'HEAD');