Issue #1860026 by aspilicious, David_Rothstein, katbailey, rootatwc: Remove hook_exit() for cached page requests, and decide between it and the onTerminate eventotherwise.

core/includes/bootstrap.inc

@@ -1443,7 +1443,7 @@ function drupal_serve_page_from_cache(stdClass $cache) {
  * Defines the critical hooks that force modules to always be loaded.
  */
 function bootstrap_hooks() {
-  return array('exit', 'watchdog');
+  return array('watchdog');
 }
 
 /**
@@ -2353,11 +2353,6 @@ function _drupal_bootstrap_page_cache() {
       date_default_timezone_set(drupal_get_user_timezone());
 
       drupal_serve_page_from_cache($cache);
-      // If the skipping of the bootstrap hooks is not enforced, call
-      // hook_exit.
-      if (variable_get('page_cache_invoke_hooks', TRUE)) {
-        bootstrap_invoke_all('exit');
-      }
       // We are done.
       exit;
     }

core/modules/overlay/overlay.module

@@ -171,9 +171,7 @@ function overlay_init() {
  * the supplemental regions of the overlay on the next page request.
  */
 function overlay_exit() {
-  // Check that we are in an overlay child page. Note that this should never
-  // return TRUE on a cached page view, since the child mode is not set until
-  // overlay_init() is called.
+  // Check that we are in an overlay child page.
   if (overlay_get_mode() == 'child') {
     // Load any markup that was stored earlier in the page request, via calls
     // to overlay_store_rendered_content(). If none was stored, this is not a

core/modules/system/lib/Drupal/system/Tests/Bootstrap/HookExitTest.php

@@ -33,7 +33,7 @@ class HookExitTest extends WebTestBase {
    * Tests calling of hook_exit().
    */
   function testHookExit() {
-    // Test with cache disabled. Boot and exit should always fire.
+    // Test with cache disabled. Exit should always fire.
     $config = config('system.performance');
     $config->set('cache.page.enabled', 0);
     $config->save();
@@ -42,14 +42,18 @@ class HookExitTest extends WebTestBase {
     $calls = 1;
     $this->assertEqual(db_query('SELECT COUNT(*) FROM {watchdog} WHERE type = :type AND message = :message', array(':type' => 'system_test', ':message' => 'hook_exit'))->fetchField(), $calls, 'hook_exit called with disabled cache.');
 
-    // Test with normal cache. Exit should be called.
+    // Test with normal cache. On the first call, exit should fire
+    // (since cache is empty), but on the second call it should not be fired.
     $config->set('cache.page.enabled', 1);
     $config->save();
     $this->drupalGet('');
     $calls++;
-    $this->assertEqual(db_query('SELECT COUNT(*) FROM {watchdog} WHERE type = :type AND message = :message', array(':type' => 'system_test', ':message' => 'hook_exit'))->fetchField(), $calls, 'hook_exit called with normal cache.');
+    $this->assertEqual(db_query('SELECT COUNT(*) FROM {watchdog} WHERE type = :type AND message = :message', array(':type' => 'system_test', ':message' => 'hook_exit'))->fetchField(), $calls, 'hook_exit called with normal cache and no cached page.');
+    $this->assertTrue(cache('page')->get(url('', array('absolute' => TRUE))), 'Page has been cached.');
+    $this->drupalGet('');
+    $this->assertEqual(db_query('SELECT COUNT(*) FROM {watchdog} WHERE type = :type AND message = :message', array(':type' => 'system_test', ':message' => 'hook_exit'))->fetchField(), $calls, 'hook_exit not called with normal cache and a cached page.');
 
-    // Exit should not fire since the page is cached.
+    // Test with aggressive cache. Exit should not fire since page is cached.
     variable_set('page_cache_invoke_hooks', FALSE);
     $this->assertTrue(cache('page')->get(url('', array('absolute' => TRUE))), 'Page has been cached.');
     $this->drupalGet('');

core/modules/system/system.api.php

@@ -318,26 +318,19 @@ function hook_element_info_alter(&$type) {
 /**
  * Perform cleanup tasks.
  *
- * This hook is run at the end of each page request. It is often used for
- * page logging and specialized cleanup. This hook MUST NOT print anything
- * because by the time it runs the response is already sent to the browser.
+ * This hook is run at the end of each non-cached page request. It is often
+ * used for page logging and specialized cleanup. This hook MUST NOT print
+ * anything because by the time it runs the response is already sent to the
+ * browser.
  *
- * Only use this hook if your code must run even for cached page views.
- * If you have code which must run once on all non-cached pages, use
- * hook_init() instead. That is the usual case. If you implement this hook
- * and see an error like 'Call to undefined function', it is likely that
- * you are depending on the presence of a module which has not been loaded yet.
- * It is not loaded because Drupal is still in bootstrap mode.
+ * This hook is not run on cached pages.
  *
  * @param $destination
  *   If this hook is invoked as part of a drupal_goto() call, then this argument
  *   will be a fully-qualified URL that is the destination of the redirect.
  */
 function hook_exit($destination = NULL) {
-  db_update('counter')
-    ->expression('hits', 'hits + 1')
-    ->condition('type', 1)
-    ->execute();
+  watchdog('mymodule', 'Page was built for user %name.', array('%name' => user_format_name($GLOBALS['user'])), WATCHDOG_INFO);
 }
 
 /**