wp-optimize / cache / class-wpo-page-cache.php

class-wpo-page-cache.php in WP-Optimize – Cache, Compress images, Minify & Clean database to boost page speed & performance 3.2.3, at cache/class-wpo-page-cache.php

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1	<?php
2	/**
3	* Page caching functionality
4	*
5	* Acknowledgement: The page cache functionality was loosely based on the simple cache plugin - https://github.com/tlovett1/simple-cache
6	*/
7
8	if (!defined('ABSPATH')) die('No direct access allowed');
9
10	/**
11	* Base cache directory, everything else goes under here
12	*/
13	if (!defined('WPO_CACHE_DIR')) define('WPO_CACHE_DIR', untrailingslashit(WP_CONTENT_DIR).'/wpo-cache');
14
15	/**
16	* Extensions directory.
17	*/
18	if (!defined('WPO_CACHE_EXT_DIR')) define('WPO_CACHE_EXT_DIR', dirname(__FILE__).'/extensions');
19
20	/**
21	* Directory that stores config and related files
22	*/
23	if (!defined('WPO_CACHE_CONFIG_DIR')) define('WPO_CACHE_CONFIG_DIR', WPO_CACHE_DIR.'/config');
24
25	/**
26	* Directory that stores the cache, including gzipped files and mobile specifc cache
27	*/
28	if (!defined('WPO_CACHE_FILES_DIR')) define('WPO_CACHE_FILES_DIR', untrailingslashit(WP_CONTENT_DIR).'/cache/wpo-cache');
29
30	if (!class_exists('WPO_Cache_Config')) require_once(dirname(__FILE__) . '/class-wpo-cache-config.php');
31	if (!class_exists('WPO_Cache_Rules')) require_once(dirname(__FILE__) . '/class-wpo-cache-rules.php');
32
33	if (!class_exists('WP_Optimize_Detect_Cache_Plugins')) require_once(dirname(__FILE__) . '/class-wpo-detect-cache-plugins.php');
34
35	if (!class_exists('WP_Optimize_Page_Cache_Preloader')) require_once(dirname(__FILE__) . '/class-wpo-cache-preloader.php');
36	if (!class_exists('WPO_Cache_Config')) require_once(dirname(__FILE__) . '/class-wpo-cache-config.php');
37	if (!class_exists('WPO_Cache_Rules')) require_once(dirname(__FILE__) . '/class-wpo-cache-rules.php');
38
39	if (!class_exists('Updraft_Abstract_Logger')) require_once(WPO_PLUGIN_MAIN_PATH.'includes/class-updraft-abstract-logger.php');
40	if (!class_exists('Updraft_PHP_Logger')) require_once(WPO_PLUGIN_MAIN_PATH.'includes/class-updraft-php-logger.php');
41
42	require_once dirname(__FILE__) . '/file-based-page-cache-functions.php';
43
44	if (version_compare(PHP_VERSION, '5.3.0') >= 0) {
45	require_once dirname(__FILE__) . '/php-5.3-functions.php';
46	}
47
48	wpo_cache_load_extensions();
49
50	if (!class_exists('WPO_Page_Cache')) :
51
52	class WPO_Page_Cache {
53
54	/**
55	* Cache config object
56	*
57	* @var mixed
58	*/
59	public $config;
60
61	/**
62	* Logger for this class
63	*
64	* @var mixed
65	*/
66	public $logger;
67
68	/**
69	* Instance of this class
70	*
71	* @var mixed
72	*/
73	public static $instance;
74
75	/**
76	* Store last advanced cache file writing status
77	* If true then last writing finished with error
78	*
79	* @var bool
80	*/
81	public $advanced_cache_file_writing_error;
82
83	/**
84	* Store errors
85	*
86	* @var array
87	*/
88	private $_errors = array();
89
90	/**
91	* Last advanced cache file content
92	*
93	* @var string
94	*/
95	public $advanced_cache_file_content;
96
97	/**
98	* Store the latest advanced-cache.php version required
99	*
100	* @var string
101	*/
102	private $_minimum_advanced_cache_file_version = '3.0.17';
103
104	/**
105	* Set everything up here
106	*/
107	public function __construct() {
108	$this->config = WPO_Cache_Config::instance();
109	$this->rules = WPO_Cache_Rules::instance();
110	$this->logger = new Updraft_PHP_Logger();
111
112	add_action('activate_plugin', array($this, 'activate_deactivate_plugin'));
113	add_action('deactivate_plugin', array($this, 'activate_deactivate_plugin'));
114
115	/**
116	* Regenerate config file on cache flush.
117	*/
118	add_action('wpo_cache_flush', array($this, 'update_cache_config'));
119	add_action('wpo_cache_flush', array($this, 'delete_cache_size_information'));
120
121	// Add purge cache link to admin bar.
122	add_filter('wpo_cache_admin_bar_menu_items', array($this, 'admin_bar_purge_cache'), 20, 1);
123
124	// Handle single page purge.
125	add_action('wp_loaded', array($this, 'handle_purge_single_page_cache'));
126
127	add_action('admin_init', array($this, 'admin_init'));
128
129	$this->check_compatibility_issues();
130	}
131
132	/**
133	* Do required actions on activate/deactivate any plugin.
134	*/
135	public function activate_deactivate_plugin() {
136
137	$this->update_cache_config();
138
139	/**
140	* Filters whether activating / deactivating a plugin will purge the cache.
141	*/
142	if (apply_filters('wpo_purge_page_cache_on_activate_deactivate_plugin', true)) {
143	$this->purge();
144	}
145	}
146
147	/**
148	* Check if current user can purge cache.
149	*
150	* @return bool
151	*/
152	public function can_purge_cache() {
153	if (is_multisite()) return $this->is_enabled() && (current_user_can('manage_network_options') \|\| WP_Optimize()->can_purge_the_cache());
154	return $this->is_enabled() && (current_user_can('manage_options') \|\| WP_Optimize()->can_purge_the_cache());
155	}
156
157	/**
158	* Add Purge from cache in admin bar.
159	*
160	* @param array $menu_items
161	* @return array
162	*/
163	public function admin_bar_purge_cache($menu_items) {
164	global $pagenow;
165	if (!$this->can_purge_cache()) return $menu_items;
166
167	$act_url = remove_query_arg(array('wpo_single_page_cache_purged', 'wpo_all_pages_cache_purged'));
168
169	$cache_size = $this->get_cache_size();
170	$cache_size_info = '<h4>'.__('Page cache', 'wp-optimize').'</h4>';
171	$cache_size_info .= '<span>'.__('Cache size:', 'wp-optimize').' '. WP_Optimize()->format_size($cache_size['size']).' '.sprintf(__('(%d files)', 'wp-optimize'), $cache_size['file_count']).'</span>';
172
173	$menu_items[] = array(
174	'id' => 'wpo_cache_stats',
175	'title' => $cache_size_info,
176	'meta' => array(
177	'class' => 'wpo-cache-stats',
178	),
179	'parent' => 'wpo_purge_cache',
180	);
181
182	$menu_items[] = array(
183	'id' => 'wpo_purge_all_pages_cache',
184	'title' => __('Purge cache for all pages', 'wp-optimize'),
185	'href' => add_query_arg('_wpo_purge', wp_create_nonce('wpo_purge_all_pages_cache'), $act_url),
186	'meta' => array(
187	'title' => __('Purge cache for all pages', 'wp-optimize'),
188	),
189	'parent' => 'wpo_purge_cache',
190	);
191
192	if (!is_admin() \|\| 'post.php' == $pagenow) {
193	$menu_items[] = array(
194	'id' => 'wpo_purge_this_page_cache',
195	'title' => __('Purge cache for this page', 'wp-optimize'),
196	'href' => add_query_arg('_wpo_purge', wp_create_nonce('wpo_purge_single_page_cache'), $act_url),
197	'meta' => array(
198	'title' => __('Purge cache for this page', 'wp-optimize'),
199	),
200	'parent' => 'wpo_purge_cache',
201	);
202	}
203
204	return $menu_items;
205
206	}
207
208	/**
209	* Check if purge single page action sent and purge cache.
210	*/
211	public function handle_purge_single_page_cache() {
212
213	if (!$this->can_purge_cache()) return;
214
215	if (isset($_GET['wpo_single_page_cache_purged']) \|\| isset($_GET['wpo_all_pages_cache_purged'])) {
216	if (isset($_GET['wpo_single_page_cache_purged'])) {
217	$notice_function = $_GET['wpo_single_page_cache_purged'] ? 'notice_purge_single_page_cache_success' : 'notice_purge_single_page_cache_error';
218	} else {
219	$notice_function = $_GET['wpo_all_pages_cache_purged'] ? 'notice_purge_all_pages_cache_success' : 'notice_purge_all_pages_cache_error';
220	}
221
222	add_action('admin_notices', array($this, $notice_function));
223
224	return;
225	}
226
227	if (!isset($_GET['_wpo_purge'])) return;
228
229	if (wp_verify_nonce($_GET['_wpo_purge'], 'wpo_purge_single_page_cache')) {
230	$success = false;
231
232	if (is_admin()) {
233	$post = isset($_GET['post']) ? (int) $_GET['post'] : 0;
234	if ($post > 0) {
235	$success = self::delete_single_post_cache($post);
236	}
237	} else {
238	$success = self::delete_cache_by_url(wpo_current_url());
239	}
240
241	// remove nonce from url and reload page.
242	wp_redirect(add_query_arg('wpo_single_page_cache_purged', $success, remove_query_arg('_wpo_purge')));
243	exit;
244
245	} elseif (wp_verify_nonce($_GET['_wpo_purge'], 'wpo_purge_all_pages_cache')) {
246	$success = self::purge();
247
248	// remove nonce from url and reload page.
249	wp_redirect(add_query_arg('wpo_all_pages_cache_purged', $success, remove_query_arg('_wpo_purge')));
250	exit;
251	}
252	}
253
254	/**
255	* Show notification when page cache purged successfully.
256	*/
257	public function notice_purge_single_page_cache_success() {
258	$this->show_notice(__('The page cache was successfully purged.', 'wp-optimize'), 'success');
259	}
260
261	/**
262	* Show notification when page cache wasn't purged.
263	*/
264	public function notice_purge_single_page_cache_error() {
265	$this->show_notice(__('The page cache was not purged.', 'wp-optimize'), 'error');
266	}
267
268	/**
269	* Show notification when all pages cache purged successfully.
270	*/
271	public function notice_purge_all_pages_cache_success() {
272	$this->show_notice(__('The page cache was successfully purged.', 'wp-optimize'), 'success');
273	}
274
275	/**
276	* Show notification when all pages cache wasn't purged.
277	*/
278	public function notice_purge_all_pages_cache_error() {
279	$this->show_notice(__('The page cache was not purged.', 'wp-optimize'), 'error');
280	}
281
282	/**
283	* Show notification in WordPress admin.
284	*
285	* @param string $message HTML (no further escaping is performed)
286	* @param string $type error, warning, success, or info
287	*/
288	public function show_notice($message, $type) {
289	global $current_screen;
290
291	if ($current_screen && is_callable(array($current_screen, 'is_block_editor')) && $current_screen->is_block_editor()) : ?>
292	<script>
293	window.addEventListener('load', function() {
294	(function(wp) {
295	if (window.wp && wp.hasOwnProperty('data') && 'function' == typeof wp.data.dispatch) {
296	wp.data.dispatch('core/notices').createNotice(
297	'<?php echo $type; ?>',
298	'<?php echo $message; ?>',
299	{
300	isDismissible: true,
301	}
302	);
303	}
304	})(window.wp);
305	});
306	</script>
307	<?php else : ?>
308	<div class="notice wpo-notice notice-<?php echo $type; ?> is-dismissible">
309	<p><?php echo $message; ?></p>
310	</div>
311	<?php
312	endif;
313	}
314
315	/**
316	* Enables page cache
317	*
318	* @param bool $force_enable - Force regenerating everything. E.g. we want to do that when saving the settings
319	*
320	* @return WP_Error\|bool - true on success, error otherwise
321	*/
322	public function enable($force_enable = false) {
323	static $already_ran_enable = false;
324
325	if ($already_ran_enable) return $already_ran_enable;
326
327	$folders_created = $this->create_folders();
328	if (is_wp_error($folders_created)) {
329	$already_ran_enable = $folders_created;
330	return $already_ran_enable;
331	}
332
333	// if WPO_ADVANCED_CACHE isn't set, or environment doesn't contain the right constant, force regeneration
334	if (!defined('WPO_ADVANCED_CACHE') \|\| !defined('WP_CACHE')) {
335	$force_enable = true;
336	}
337
338	if (!$force_enable) {
339	$already_ran_enable = true;
340	return true;
341	}
342
343	if (!$this->write_advanced_cache() && version_compare($this->get_advanced_cache_version(), $this->_minimum_advanced_cache_file_version, '<')) {
344	$message = sprintf("The request to write the file %s failed. ", htmlspecialchars($this->get_advanced_cache_filename()));
345	$message .= ' '.__('Please check file and directory permissions on the file paths up to this point, and your PHP error log.', 'wp-optimize');
346
347	if (!defined('WP_CLI') \|\| !WP_CLI) {
348	$message .= "\n\n".sprintf(__('1. Please navigate, via FTP, to the folder - %s', 'wp-optimize'), htmlspecialchars(dirname($this->get_advanced_cache_filename())));
349	$message .= "\n".__('2. Edit or create a file with the name advanced-cache.php', 'wp-optimize');
350	$message .= "\n".__('3. Copy and paste the following lines into the file:', 'wp-optimize');
351	}
352
353	$already_ran_enable = new WP_Error("write_advanced_cache", $message);
354	return $already_ran_enable;
355	}
356
357	if (!$this->write_wp_config(true)) {
358	$already_ran_enable = new WP_Error("write_wp_config", "Could not turn on the WP_CACHE constant in wp-config.php. Check your permissions.");
359	return $already_ran_enable;
360	}
361
362	if (!$this->verify_cache()) {
363	$errors = $this->get_errors();
364	$already_ran_enable = new WP_Error("verify_cache", "Could not verify if the cache was enabled: \n".implode("\n- ", $errors));
365	return $already_ran_enable;
366	}
367
368	$already_ran_enable = true;
369
370	return true;
371	}
372
373	/**
374	* Disables page cache
375	*
376	* @return bool - true on success, false otherwise
377	*/
378	public function disable() {
379	$ret = true;
380
381	$advanced_cache_file = $this->get_advanced_cache_filename();
382
383	// N.B. The only use of WP_CACHE in WP core is to include('advanced-cache.php') (and run a function if it's then defined); so, if the decision to leave it enable is, for some unexpected reason, technically incorrect, it still can't cause a problem.
384	$disabled_wp_config = $this->write_wp_config(false);
385	if (!$disabled_wp_config) {
386	$this->log("Could not turn off the WP_CACHE constant in wp-config.php");
387	$this->add_warning('error_disabling', __('Could not turn off the WP_CACHE constant in wp-config.php', 'wp-optimize'));
388	}
389
390	$disabled_advanced_cache = true;
391	// First try to remove (so that it doesn't look to any other plugin like the file is already 'claimed')
392	// We only touch advanched-cache.php and wp-config.php if it appears that we were in control of advanced-cache.php
393	if (!file_exists($advanced_cache_file) \|\| false !== strpos(file_get_contents($advanced_cache_file), 'WP-Optimize advanced-cache.php')) {
394	if (file_exists($advanced_cache_file) && (!unlink($advanced_cache_file) && false === file_put_contents($advanced_cache_file, "<?php\n// WP-Optimize: page cache disabled"))) {
395	$disabled_advanced_cache = false;
396	$this->log("The request to the filesystem to remove or empty advanced-cache.php failed");
397	$this->add_warning('error_disabling', __('The request to the filesystem to remove or empty advanced-cache.php failed', 'wp-optimize'));
398	}
399	}
400
401	// If both actions failed, the cache wasn't disabled. So we send an error. If only one succeeds, it will still be disabled.
402	if (!$disabled_wp_config && !$disabled_advanced_cache) {
403	$ret = new WP_Error('error_disabling_cache', __('The page caching could not be disabled: the WP_CACHE constant could not be removed from wp-config.php and the request to the filesystem to remove or empty advanced-cache.php failed.', 'wp-optimize'));
404	}
405
406	// Delete cache to avoid stale cache on next activation
407	$this->purge();
408
409	return $ret;
410	}
411
412
413	/**
414	* Purges the cache
415	*
416	* @return bool - true on success, false otherwise
417	*/
418	public function purge() {
419
420	if (!self::delete(WPO_CACHE_FILES_DIR)) {
421	$this->log("The request to the filesystem to delete the cache failed");
422	return false;
423	}
424
425	/**
426	* Fires after purging the cache
427	*/
428	do_action('wpo_cache_flush');
429
430	return true;
431	}
432
433	/**
434	* Purges the cache
435	*
436	* @return bool - true on success, false otherwise
437	*/
438	public function clean_up() {
439
440	$this->disable();
441
442	if (!self::delete(WPO_CACHE_DIR, true)) {
443	$this->log("The request to the filesystem to clean up the cache failed");
444	return false;
445	}
446
447	return true;
448	}
449
450	/**
451	* Check if cache is enabled and working
452	*
453	* @return bool - true on success, false otherwise
454	*/
455	public function is_enabled() {
456
457	if (!defined('WP_CACHE') \|\| !WP_CACHE) {
458	return false;
459	}
460
461	if (!defined('WPO_ADVANCED_CACHE') \|\| !WPO_ADVANCED_CACHE) {
462	return false;
463	}
464
465	if (!file_exists(WPO_CACHE_CONFIG_DIR . '/'.$this->get_cache_config_filename())) {
466	return false;
467	}
468
469	return true;
470	}
471
472	/**
473	* Create the folder structure needed for cache to work
474	*
475	* @return bool - true on success, false otherwise
476	*/
477	private function create_folders() {
478
479	if (!is_dir(WPO_CACHE_DIR) && !wp_mkdir_p(WPO_CACHE_DIR)) {
480	return new WP_Error('create_folders', sprintf(__('The request to the filesystem failed: unable to create directory %s. Please check your file permissions.'), str_ireplace(ABSPATH, '', WPO_CACHE_DIR)));
481	}
482
483	if (!is_dir(WPO_CACHE_CONFIG_DIR) && !wp_mkdir_p(WPO_CACHE_CONFIG_DIR)) {
484	return new WP_Error('create_folders', sprintf(__('The request to the filesystem failed: unable to create directory %s. Please check your file permissions.'), str_ireplace(ABSPATH, '', WPO_CACHE_CONFIG_DIR)));
485	}
486
487	if (!is_dir(WPO_CACHE_FILES_DIR)) {
488	if (!wp_mkdir_p(WPO_CACHE_FILES_DIR)) {
489	return new WP_Error('create_folders', sprintf(__('The request to the filesystem failed: unable to create directory %s. Please check your file permissions.'), str_ireplace(ABSPATH, '', WPO_CACHE_FILES_DIR)));
490	} else {
491	wpo_disable_cache_directories_viewing();
492	}
493	}
494
495	return true;
496	}
497
498	/**
499	* Get advanced-cache.php file name with full path.
500	*
501	* @return string
502	*/
503	public function get_advanced_cache_filename() {
504	return untrailingslashit(WP_CONTENT_DIR) . '/advanced-cache.php';
505	}
506
507	/**
508	* Get advanced-cache.php file name with full path.
509	*
510	* @return string
511	*/
512	public function get_cache_config_filename() {
513	$url = parse_url(network_site_url());
514
515	if (isset($url['port']) && '' != $url['port'] && 80 != $url['port']) {
516	return 'config-'.$url['host'].'-port'.$url['port'].'.php';
517	} else {
518	return 'config-'.$url['host'].'.php';
519	}
520	}
521
522	/**
523	* Writes advanced-cache.php
524	*
525	* @param boolean $update_required - Whether the update is required or not.
526	* @return bool
527	*/
528	private function write_advanced_cache($update_required = false) {
529	$config_file_basename = $this->get_cache_config_filename();
530	$cache_file_basename = untrailingslashit(plugin_dir_path(__FILE__));
531	$plugin_basename = basename(WPO_PLUGIN_MAIN_PATH);
532	$cache_path = '/wpo-cache';
533	$cache_files_path = '/cache/wpo-cache';
534	$cache_extensions_path = WPO_CACHE_EXT_DIR;
535	$wpo_version = WPO_VERSION;
536	$wpo_home_url = trailingslashit(home_url());
537
538	// CS does not like heredoc
539	// phpcs:disable
540	$this->advanced_cache_file_content = <<<EOF
541	<?php
542
543	if (!defined('ABSPATH')) die('No direct access allowed');
544
545	// WP-Optimize advanced-cache.php (written by version: $wpo_version) (do not change this line, it is used for correctness checks)
546
547	if (!defined('WPO_ADVANCED_CACHE')) define('WPO_ADVANCED_CACHE', true);
548
549	\$possible_plugin_locations = array(
550	defined('WP_PLUGIN_DIR') ? WP_PLUGIN_DIR.'/$plugin_basename/cache' : false,
551	defined('WP_CONTENT_DIR') ? WP_CONTENT_DIR.'/plugins/$plugin_basename/cache' : false,
552	dirname(__FILE__).'/plugins/$plugin_basename/cache',
553	'$cache_file_basename',
554	);
555
556	\$plugin_location = false;
557
558	foreach (\$possible_plugin_locations as \$possible_location) {
559	if (false !== \$possible_location && @file_exists(\$possible_location.'/file-based-page-cache.php')) {
560	\$plugin_location = \$possible_location;
561	break;
562	}
563	}
564
565	if (false === \$plugin_location) {
566	if (!defined('WPO_PLUGIN_LOCATION_NOT_FOUND')) define('WPO_PLUGIN_LOCATION_NOT_FOUND', true);
567	\$protocol = \$_SERVER['REQUEST_SCHEME'];
568	\$host = \$_SERVER['HTTP_HOST'];
569	\$request_uri = \$_SERVER['REQUEST_URI'];
570	if (strcasecmp('$wpo_home_url', \$protocol . '://' . \$host . \$request_uri) === 0) {
571	error_log('WP-Optimize: No caching took place, because the plugin location could not be found');
572	}
573	} else {
574	if (!defined('WPO_PLUGIN_LOCATION_NOT_FOUND')) define('WPO_PLUGIN_LOCATION_NOT_FOUND', false);
575	}
576
577	if (is_admin()) { return; }
578
579	if (!defined('WPO_CACHE_DIR')) define('WPO_CACHE_DIR', WP_CONTENT_DIR.'$cache_path');
580	if (!defined('WPO_CACHE_CONFIG_DIR')) define('WPO_CACHE_CONFIG_DIR', WPO_CACHE_DIR.'/config');
581	if (!defined('WPO_CACHE_FILES_DIR')) define('WPO_CACHE_FILES_DIR', WP_CONTENT_DIR.'$cache_files_path');
582	if (false !== \$plugin_location) {
583	if (!defined('WPO_CACHE_EXT_DIR')) define('WPO_CACHE_EXT_DIR', \$plugin_location.'/extensions');
584	} else {
585	if (!defined('WPO_CACHE_EXT_DIR')) define('WPO_CACHE_EXT_DIR', '$cache_extensions_path');
586	}
587
588	if (!@file_exists(WPO_CACHE_CONFIG_DIR . '/$config_file_basename')) { return; }
589
590	\$GLOBALS['wpo_cache_config'] = @json_decode(file_get_contents(WPO_CACHE_CONFIG_DIR . '/$config_file_basename'), true);
591
592	if (empty(\$GLOBALS['wpo_cache_config'])) {
593	include_once(WPO_CACHE_CONFIG_DIR . '/$config_file_basename');
594	}
595
596	if (empty(\$GLOBALS['wpo_cache_config']) \|\| empty(\$GLOBALS['wpo_cache_config']['enable_page_caching'])) { return; }
597
598	if (false !== \$plugin_location) { include_once(\$plugin_location.'/file-based-page-cache.php'); }
599
600	EOF;
601
602	// phpcs:enable
603	$advanced_cache_filename = $this->get_advanced_cache_filename();
604
605	// If the file content is already up to date, success
606	if (is_file($advanced_cache_filename) && file_get_contents($advanced_cache_filename) === $this->advanced_cache_file_content) {
607	$this->advanced_cache_file_writing_error = false;
608	return true;
609	}
610
611	// check if we can't write the advanced cache file
612	// case 1: the directory is read-only and the file doesn't exist
613	if (!is_file($advanced_cache_filename) && !is_writable(dirname($advanced_cache_filename))) {
614	$this->advanced_cache_file_writing_error = true;
615	return false;
616	}
617
618	// case 2: the file already exists but it's read-only
619	if (is_file($advanced_cache_filename) && !is_writable($advanced_cache_filename)) {
620	if (version_compare($this->get_advanced_cache_version(), $this->_minimum_advanced_cache_file_version, '<') \|\| $update_required) {
621	$this->advanced_cache_file_writing_error = true;
622	return false;
623	} else {
624	$this->advanced_cache_file_writing_error = false;
625	return true;
626	}
627	}
628
629	if (!file_put_contents($this->get_advanced_cache_filename(), $this->advanced_cache_file_content)) {
630	$this->advanced_cache_file_writing_error = true;
631	return false;
632	}
633
634	$this->advanced_cache_file_writing_error = false;
635	return true;
636	}
637
638	/**
639	* Update advanced cache version if needed.
640	*/
641	public function maybe_update_advanced_cache() {
642
643	if (!$this->is_enabled()) return;
644
645	if (!defined('WPO_PLUGIN_LOCATION_NOT_FOUND') \|\| (defined('WPO_PLUGIN_LOCATION_NOT_FOUND') && true === WPO_PLUGIN_LOCATION_NOT_FOUND)) {
646	if (!$this->write_advanced_cache(true)) {
647	add_action('admin_notices', array($this, 'show_admin_notice_advanced_cache'));
648	}
649	}
650
651	// from 3.0.17 we use more secure way to store cache config files and need update advanced-cache.php
652	$advanced_cache_current_version = $this->get_advanced_cache_version();
653	if ($advanced_cache_current_version && version_compare($advanced_cache_current_version, $this->_minimum_advanced_cache_file_version, '>=')) return;
654
655	if (!$this->write_advanced_cache()) {
656	add_action('admin_notices', array($this, 'notice_advanced_cache_autoupdate_error'));
657	} else {
658	$this->update_cache_config();
659	}
660	}
661
662	/**
663	* Show notification when advanced-cache.php could not be updated.
664	*/
665	public function notice_advanced_cache_autoupdate_error() {
666	$this->show_notice(__('The file advanced-cache.php needs to be updated, but the automatic process failed.', 'wp-optimize').
667	' <a href="'.admin_url('admin.php?page=wpo_cache').'">'.__('Please try to disable and then re-enable the WP-Optimize cache manually.', 'wp-optimize').'</a>', 'error');
668	}
669
670	/**
671	* Get WPO version number from advanced-cache.php file.
672	*
673	* @return bool\|mixed
674	*/
675	public function get_advanced_cache_version() {
676	if (!is_file($this->get_advanced_cache_filename())) return false;
677
678	$version = false;
679	$content = file_get_contents($this->get_advanced_cache_filename());
680
681	if (preg_match('/WP\-Optimize advanced\-cache\.php $written by version\: (.+)$/Ui', $content, $match)) {
682	$version = $match[1];
683	}
684
685	return $version;
686	}
687
688	/**
689	* Set WP_CACHE on or off in wp-config.php
690	*
691	* @param boolean $status value of WP_CACHE.
692	* @return boolean true if the value was set, false otherwise
693	*/
694	private function write_wp_config($status = true) {
695	// If we changed the value in wp-config, save it, in case we need to change it again in the same run.
696	static $changed = false;
697
698	if (defined('WP_CACHE') && WP_CACHE === $status && !$changed) {
699	return true;
700	}
701
702	$config_path = $this->_get_wp_config();
703
704	// Couldn't find wp-config.php.
705	if (!$config_path) {
706	return false;
707	}
708
709	$config_file_string = file_get_contents($config_path);
710
711	// Config file is empty. Maybe couldn't read it?
712	if (empty($config_file_string)) {
713	return false;
714	}
715
716	$config_file = preg_split("#(\n\|\r\n)#", $config_file_string);
717	$line_key = false;
718
719	foreach ($config_file as $key => $line) {
720	if (!preg_match('/^\sdefine\(\s(\'\|")([A-Z_]+)(\'\|")(.*)/i', $line, $match)) {
721	continue;
722	}
723
724	if ('WP_CACHE' === $match[2]) {
725	$line_key = $key;
726	}
727	}
728
729	if (false !== $line_key) {
730	unset($config_file[$line_key]);
731	}
732
733
734	if ($status) {
735	array_shift($config_file);
736	array_unshift($config_file, '<?php', "define('WP_CACHE', true); // WP-Optimize Cache");
737	}
738
739	foreach ($config_file as $key => $line) {
740	if ('' === $line) {
741	unset($config_file[$key]);
742	}
743	}
744	if (!file_put_contents($config_path, implode(PHP_EOL, $config_file))) {
745	return false;
746	}
747	$changed = true;
748	return true;
749	}
750
751	/**
752	* Verify we can write to the file system
753	*
754	* @return boolean
755	*/
756	private function verify_cache() {
757	if (function_exists('clearstatcache')) {
758	clearstatcache();
759	}
760	$errors = 0;
761
762	// First check wp-config.php.
763	if (!$this->_get_wp_config() && !is_writable($this->_get_wp_config())) {
764	$this->log("Unable to write to or find wp-config.php; please check file/folder permissions");
765	$this->add_warning('verify_cache', __("Unable to write to or find wp-config.php; please check file/folder permissions.", 'wp-optimize'));
766	}
767
768	$advanced_cache_file = untrailingslashit(WP_CONTENT_DIR).'/advanced-cache.php';
769
770	// Now check wp-content. We need to be able to create files of the same user as this file.
771	if ((!file_exists($advanced_cache_file) \|\| false === strpos(file_get_contents($advanced_cache_file), 'WP-Optimize advanced-cache.php')) && !is_writable($advanced_cache_file) && !is_writable(untrailingslashit(WP_CONTENT_DIR))) {
772	$this->log("Unable to write the file advanced-cache.php inside the wp-content folder; please check file/folder permissions");
773	$this->add_error('verify_cache', __("Unable to write the file advanced-cache.php inside the wp-content folder; please check file/folder permissions", 'wp-optimize'));
774	$errors++;
775	}
776
777	if (file_exists(WPO_CACHE_FILES_DIR)) {
778	if (!is_writable(WPO_CACHE_FILES_DIR)) {
779	$this->log("Unable to write inside the cache files folder; please check file/folder permissions");
780	$this->add_warning('verify_cache', sprintf(__("Unable to write inside the cache files folder (%s); please check file/folder permissions (no cache files will be able to be created otherwise)", 'wp-optimize'), WPO_CACHE_FILES_DIR));
781	}
782	}
783
784	if (file_exists(WPO_CACHE_CONFIG_DIR)) {
785	if (!is_writable(WPO_CACHE_CONFIG_DIR)) {
786	$this->log("Unable to write inside the cache configuration folder; please check file/folder permissions");
787	// If the config exists, only send a warning. Otherwise send an error.
788	$type = 'warning';
789	if (!file_exists(WPO_CACHE_CONFIG_DIR . '/'.$this->get_cache_config_filename())) {
790	$type = 'error';
791	$errors++;
792	}
793	$this->add_error('verify_cache', sprintf(__("Unable to write inside the cache configuration folder (%s); please check file/folder permissions", 'wp-optimize'), WPO_CACHE_CONFIG_DIR), $type);
794	}
795	}
796
797	return !$errors;
798	}
799
800	/**
801	* Update cache config. Used to support 3d party plugins.
802	*/
803	public function update_cache_config() {
804	// get current cache settings.
805	$current_config = $this->config->get();
806	// and call update to change if need cookies and query variable names.
807	$this->config->update($current_config, true);
808	}
809
810	/**
811	* Delete information about cache size.
812	*/
813	public function delete_cache_size_information() {
814	delete_transient('wpo_get_cache_size');
815	}
816
817	/**
818	* Get current cache size.
819	*
820	* @return array
821	*/
822	public function get_cache_size() {
823	$cache_size = get_transient('wpo_get_cache_size');
824
825	if (!empty($cache_size)) return $cache_size;
826
827	$infos = $this->get_dir_infos(WPO_CACHE_FILES_DIR);
828	$cache_size = array(
829	'size' => $infos['size'],
830	'file_count' => $infos['file_count']
831	);
832
833	set_transient('wpo_get_cache_size', $cache_size);
834
835	return $cache_size;
836	}
837
838	/**
839	* Fetch directory informations.
840	*
841	* @param string $dir
842	* @return array
843	*/
844	private function get_dir_infos($dir) {
845	$dir_size = 0;
846	$file_count = 0;
847
848	$handle = is_dir($dir) ? opendir($dir) : false;
849
850	if (false === $handle) {
851	return array('size' => 0, 'file_count' => 0);
852	}
853
854	$file = readdir($handle);
855
856	while (false !== $file) {
857
858	if ('.' != $file && '..' != $file) {
859	$current_file = $dir.'/'.$file;
860
861	if (is_dir($current_file)) {
862	$sub_dir_infos = $this->get_dir_infos($current_file);
863	$dir_size += $sub_dir_infos['size'];
864	$file_count += $sub_dir_infos['file_count'];
865	} elseif (is_file($current_file)) {
866	$dir_size += filesize($current_file);
867	$file_count++;
868	}
869	}
870
871	$file = readdir($handle);
872
873	}
874
875	return array('size' => $dir_size, 'file_count' => $file_count);
876	}
877
878	/**
879	* Returns the path to wp-config
880	*
881	* @return string\|boolean wp-config.php path.
882	*/
883	private function _get_wp_config() {
884
885	$config_path = false;
886
887	foreach (get_included_files() as $filename) {
888	if (preg_match('/(\\\\\|\/)wp-config\.php$/i', $filename)) {
889	$config_path = $filename;
890	break;
891	}
892	}
893
894	// WP-CLI doesn't include wp-config.php that's why we use function from WP-CLI to locate config file.
895	if (!$config_path && is_callable('wpo_wp_cli_locate_wp_config')) {
896	$config_path = wpo_wp_cli_locate_wp_config();
897	}
898
899	return $config_path;
900	}
901
902	/**
903	* Util to delete folders and/or files
904	*
905	* @param string $src
906	* @return boolean
907	*/
908	public static function delete($src) {
909
910	return wpo_delete_files($src);
911
912	}
913
914	/**
915	* Delete cached files for specific url.
916	*
917	* @param string $url
918	* @param bool $recursive If true child elements will deleted too
919	*
920	* @return bool
921	*/
922	public static function delete_cache_by_url($url, $recursive = false) {
923	if (!defined('WPO_CACHE_FILES_DIR') \|\| '' == $url) return;
924
925	$path = self::get_full_path_from_url($url);
926
927	do_action('wpo_delete_cache_by_url', $url, $recursive);
928
929	return wpo_delete_files($path, $recursive);
930	}
931
932	/**
933	* Delete cached files for single post.
934	*
935	* @param integer $post_id The post ID
936	*
937	* @return bool
938	*/
939	public static function delete_single_post_cache($post_id) {
940
941	if (!defined('WPO_CACHE_FILES_DIR')) return;
942
943	$post_url = get_permalink($post_id);
944
945	$path = self::get_full_path_from_url($post_url);
946
947	// for posts with pagination run purging cache recursively.
948	$post = get_post($post_id);
949	$recursive = preg_match('/\<\!--nextpage--\>/', $post->post_content) ? true : false;
950
951	do_action('wpo_delete_cache_by_url', $post_url, $recursive);
952
953	return wpo_delete_files($path, $recursive);
954	}
955
956	/**
957	* Delete cached home page files.
958	*/
959	public static function delete_homepage_cache() {
960
961	if (!defined('WPO_CACHE_FILES_DIR')) return;
962
963	$homepage_url = get_home_url(get_current_blog_id());
964
965	$path = self::get_full_path_from_url($homepage_url);
966
967	do_action('wpo_delete_cache_by_url', $homepage_url, false);
968
969	wpo_delete_files($path, false);
970	}
971
972	/**
973	* Delete sitemap cahche.
974	*/
975	public static function delete_sitemap_cache() {
976	if (!defined('WPO_CACHE_FILES_DIR')) return;
977
978	$homepage_url = get_home_url(get_current_blog_id());
979
980	$path = trailingslashit(WPO_CACHE_FILES_DIR) . trailingslashit(wpo_get_url_path($homepage_url));
981
982	if (!is_dir($path)) return;
983
984	$handle = opendir($path);
985
986	if (false !== $handle) {
987	$file = readdir($handle);
988
989	while (false !== $file) {
990
991	if ('.' != $file && '..' != $file && is_dir($path . $file) && preg_match('/.sitemap.\.xml/i', $file)) {
992	do_action('wpo_delete_cache_by_url', $path . $file, false);
993	wpo_delete_files($path . $file, true);
994	}
995
996	$file = readdir($handle);
997	}
998	}
999
1000	closedir($handle);
1001	}
1002
1003	/**
1004	* Delete feed from cache.
1005	*/
1006	public static function delete_feed_cache() {
1007	if (!defined('WPO_CACHE_FILES_DIR')) return;
1008
1009	$homepage_url = get_home_url(get_current_blog_id());
1010
1011	$path = self::get_full_path_from_url($homepage_url) . 'feed/';
1012
1013	do_action('wpo_delete_cache_by_url', $path, true);
1014
1015	wpo_delete_files($path, true);
1016	}
1017
1018	/**
1019	* Delete post feed from cache.
1020	*/
1021	public static function delete_post_feed_cache($post_id) {
1022	if (!defined('WPO_CACHE_FILES_DIR')) return;
1023
1024	$post_url = get_permalink($post_id);
1025
1026	$path = self::get_full_path_from_url($post_url) . 'feed/';
1027
1028	do_action('wpo_delete_cache_by_url', $path, true);
1029
1030	wpo_delete_files($path, true);
1031	}
1032
1033	/**
1034	* Delete comments feed from cache.
1035	*/
1036	public static function delete_comments_feed() {
1037	if (!defined('WPO_CACHE_FILES_DIR')) return;
1038
1039	$comments_feed_url = trailingslashit(get_home_url(get_current_blog_id())) . 'comments/feed/';
1040
1041	$path = self::get_full_path_from_url($comments_feed_url);
1042
1043	do_action('wpo_delete_cache_by_url', $comments_feed_url, true);
1044
1045	wpo_delete_files($path, true);
1046
1047	// delete empty comments dir from the cache
1048	$comments_url = trailingslashit(get_home_url(get_current_blog_id())) . 'comments/';
1049	$path = self::get_full_path_from_url($comments_url);
1050
1051	if (wpo_is_empty_dir($path)) {
1052	wpo_delete_files($path, true);
1053	}
1054	}
1055
1056	/**
1057	* Returns full path to the cache folder by url.
1058	*
1059	* @param string $url
1060	* @return string
1061	*/
1062	private static function get_full_path_from_url($url) {
1063	return trailingslashit(WPO_CACHE_FILES_DIR) . trailingslashit(wpo_get_url_path($url));
1064	}
1065
1066	/**
1067	* Admin actions
1068	*
1069	* @return void
1070	*/
1071	public function admin_init() {
1072	// Maybe update the advanced cache.
1073	if ((!defined('DOING_AJAX') \|\| !DOING_AJAX) && current_user_can('update_plugins')) {
1074	$this->maybe_update_advanced_cache();
1075	}
1076	}
1077
1078	/**
1079	* Logs error messages
1080	*
1081	* @param string $message
1082	* @return null\|void
1083	*/
1084	public function log($message) {
1085	if (isset($this->logger)) {
1086	$this->logger->log($message, 'error');
1087	} else {
1088	error_log($message);
1089	}
1090	}
1091
1092	/**
1093	* Returns an instance of the current class, creates one if it doesn't exist
1094	*
1095	* @return object
1096	*/
1097	public static function instance() {
1098	if (empty(self::$instance)) {
1099	self::$instance = new self();
1100	}
1101	return self::$instance;
1102	}
1103
1104	/**
1105	* Adds an error to the error store
1106	*
1107	* @param string $code - The error code
1108	* @param string $message - The error's message
1109	* @param string $type - The error's type (error, warning)
1110	* @return void
1111	*/
1112	public function add_error($code, $message, $type = 'error') {
1113	if (!isset($this->_errors[$type])) {
1114	$this->_errors[$type] = new WP_Error($code, $message);
1115	} else {
1116	$this->_errors[$type]->add($code, $message);
1117	}
1118	}
1119
1120	/**
1121	* Adds a warning to the error store
1122	*
1123	* @param string $code - The error code
1124	* @param string $message - The error's message
1125	* @return void
1126	*/
1127	public function add_warning($code, $message) {
1128	$this->add_error($code, $message, 'warning');
1129	}
1130
1131	/**
1132	* Get all recorded errors
1133	*
1134	* @param string $type - The error type
1135	* @param boolean $get_messages_only - Whether to get only the messages, or the full WP_Error object
1136	* @return boolean\|array\|WP_Error
1137	*/
1138	public function get_errors($type = 'error', $get_messages_only = true) {
1139	if (!$this->has_errors($type)) return false;
1140	$errors = $this->_errors[$type];
1141	if ($get_messages_only) {
1142	return $errors->get_error_messages();
1143	}
1144	return $errors;
1145	}
1146
1147	/**
1148	* Check if any errors were recorded
1149	*
1150	* @param string $type - The error type
1151	* @return boolean
1152	*/
1153	public function has_errors($type = 'error') {
1154	return isset($this->_errors[$type]) && !empty($this->_errors[$type]) && $this->_errors[$type]->has_errors();
1155	}
1156
1157	/**
1158	* Check if any warnings were recorded
1159	*
1160	* @return boolean
1161	*/
1162	public function has_warnings() {
1163	return $this->has_errors('warning');
1164	}
1165
1166	/**
1167	* Check the cache compatibility issues.
1168	*/
1169	public function check_compatibility_issues() {
1170	if (!$this->is_enabled()) return;
1171
1172	if ($this->is_pagespeedninja_gzip_active()) add_action('admin_notices', array($this, 'show_pagespeedninja_gzip_notice'));
1173	if ($this->is_farfutureexpiration_gzip_active()) add_action('admin_notices', array($this, 'show_farfutureexpiration_gzip_notice'));
1174	}
1175
1176	/**
1177	* Check if PageSpeed Ninja is active and GZIP compression option is enabled.
1178	*
1179	* @return bool
1180	*/
1181	public function is_pagespeedninja_gzip_active() {
1182	if (!class_exists('PagespeedNinja')) return false;
1183
1184	$options = get_option('pagespeedninja_config');
1185	$gzip = !empty($options) ? (bool) $options['psi_EnableGzipCompression'] && (bool) $options['html_gzip'] : false;
1186
1187	return $gzip;
1188	}
1189
1190	/**
1191	* Output PageSpeed Ninja Gzip notice.
1192	*/
1193	public function show_pagespeedninja_gzip_notice() {
1194	echo '<div id="wp-optimize-pagespeedninja-gzip-notice" class="error wpo-notice"><p><b>'.__('WP-Optimize:', 'wp-optimize').'</b> '.__('Please disable the feature "Gzip compression" in PageSpeed Ninja to prevent conflicts.', 'wp-optimize').'</p></div>';
1195	}
1196
1197	/**
1198	* Check if Far Future Expiration is active and GZIP compression option is enabled.
1199	*
1200	* @return bool
1201	*/
1202	public function is_farfutureexpiration_gzip_active() {
1203	if (!class_exists('farFutureExpiration')) return false;
1204
1205	$options = get_option('far_future_expiration_settings');
1206	$gzip = !empty($options) ? (bool) $options['enable_gzip'] : false;
1207
1208	return $gzip;
1209	}
1210
1211	/**
1212	* Output Far Future Expiration Gzip notice.
1213	*/
1214	public function show_farfutureexpiration_gzip_notice() {
1215	echo '<div id="wp-optimize-pagespeedninja-gzip-notice" class="error wpo-notice"><p><b>'.__('WP-Optimize:', 'wp-optimize').'</b> '.__('Please disable the feature "Gzip compression" in Far Future Expiration to prevent conflicts.', 'wp-optimize').'</p></div>';
1216	}
1217
1218	/**
1219	* This is a notice to show users that writing `advanced-cache.php` failed
1220	*/
1221	public function show_admin_notice_advanced_cache() {
1222	$message = sprintf(__('The request to write the file %s failed.', 'wp-optimize'), htmlspecialchars($this->get_advanced_cache_filename()));
1223	$message .= ' '.__('Please check file and directory permissions on the file paths up to this point, and your PHP error log.', 'wp-optimize');
1224	WP_Optimize()->include_template('notices/cache-notice.php', false, array('message' => $message));
1225	}
1226	}
1227
1228	endif;
1229