Service Worker: Make ServiceWorkerRegistration.update() return a promise. (Blink Layout 3/3)

LayoutTests/http/tests/serviceworker/resources/update-worker.php

 <?php
-// Force the browser to cache this script. update() should always bypass this
-// cache and fetch a new version.
-header('Cache-Control: max-age=86400');
+if(!isset($_COOKIE['mode']))
+  $mode = 'init'; // For the first fetch, set the mode to 'init'.
+else
+  $mode = $_COOKIE['mode']; // $_COOKIE['mode'] is either 'normal' or 'error'.
 
+// 'init' or 'normal' mode sets the normal mimetype.
+if ($mode == 'init' || $mode == 'normal') {
+  header("Cache-Control: no-cache, must-revalidate");
+  header("Pragma: no-cache");

[nhiroki, 2015/08/10 02:32:42]

Can you move these cache-control headers to out of the if-elseif steatements?
(line 7)

+  header('Content-Type:application/javascript');
+  if ($mode == 'init')
+    setcookie('mode', 'normal'); // To make 2nd fetch to work in 'normal' mode.
+  else
+    setcookie('mode', 'error');  // To make 3rd fetch to work in 'error' mode.
+}

[nhiroki, 2015/08/10 02:32:42]

if ($mode == 'init') {
  // ...
} else if ($mode == 'normal') {
  // ...
} else if ($mode == 'error') {
  // ...
}

... could be easier to understand the state transition.

[jungkees, 2015/08/10 03:20:41]

Re-organized the blocks as you commented. Looks much clearer!

+// 'error' mode sets a disallowed mimetype.
+else if ($mode == 'error') {
+  header("Cache-Control: no-cache, must-revalidate");
+  header("Pragma: no-cache");
+  header('Content-Type:text/html');
+  unset($_COOKIE['mode']);
+  setcookie('mode', '', time() - 3600); // Delete cookie at the end of the test.
+}
 // Return a different script for each access.
-header('Content-Type:application/javascript');
-echo '// ' . microtime()
+echo '// ' . microtime();
 ?>