function flush()
{
static $done = false;
if ($done) {
return false;
}
# can't flush if WP isn't loaded
if (!function_exists('get_option')) {
return false;
}
$done = true;
global $wpdb;
$this->flush = true;
if (method_exists('static_cache', 'disable')) {
static_cache::disable();
}
# flush posts
$posts = $wpdb->get_results("SELECT ID, post_title, post_name, post_date, post_type, post_status, post_author, post_parent FROM {$wpdb->posts} WHERE post_status IN ('publish', 'private') OR post_type = 'attachment'");
# force WP widgets to flush
wp_cache_delete('widget_recent_posts', 'widget');
wp_cache_delete('recent_comments', 'widget');
wp_cache_delete('get_calendar', 'calendar');
wp_cache_delete('wp_get_archives', 'general');
wp_cache_delete('all_page_ids', 'posts');
wp_cache_delete('get_pages', 'posts');
$post_ids = array();
foreach ($posts as $post) {
$post_ids[] = $post->ID;
$this->delete($post->ID, 'posts');
$this->delete($post->ID, 'post_meta');
clean_object_term_cache($post->ID, 'post');
do_action('clean_post_cache', $post->ID);
# fill a temporary bucket so as to handle permalinks
$key = $this->key($post->ID, 'posts');
$this->cache[$key] = $post;
if (class_exists('sem_cache') && $post->post_type == 'post') {
sem_cache::do_flush_author($post->post_author);
sem_cache::do_flush_date($post->post_date);
}
}
unset($posts);
if (class_exists('sem_cache')) {
# flush get_permalink() intensive stuff before flushing terms
foreach ($post_ids as $post_id) {
sem_cache::do_flush_post($post_id);
}
# flush home
sem_cache::do_flush_home();
}
# flush terms
$terms = $wpdb->get_results("SELECT term_id, taxonomy FROM {$wpdb->term_taxonomy} WHERE count > 0");
$taxonomies = array();
$term_ids = array();
if (class_exists('sem_cache')) {
foreach ($terms as $term) {
sem_cache::do_flush_term($term->term_id, $term->taxonomy);
}
}
foreach ($terms as $term) {
$taxonomies[] = $term->taxonomy;
$term_ids[] = $term->term_id;
$this->delete($term->term_id, $term->taxonomy);
}
$taxonomies = array_unique($taxonomies);
foreach ($taxonomies as $taxonomy) {
$this->delete('all_ids', $taxonomy);
$this->delete('get', $taxonomy);
delete_option("{$taxonomy}_children");
do_action('clean_term_cache', $term_ids, $taxonomy);
}
$this->delete('last_changed', 'terms');
unset($terms);
# flush users
$user_ids = $wpdb->get_col("SELECT ID FROM {$wpdb->users}");
foreach ($user_ids as $user_id) {
$this->delete($user_id, 'users');
}
unset($user_ids);
# backup key transients
$transients = array('update_core', 'update_plugins', 'update_themes', 'sem_memberships', 'sem_update_plugins', 'sem_update_themes');
$extra = array('feed_220431e2eb0959fa9c7fcb07c6e22632', 'feed_mod_220431e2eb0959fa9c7fcb07c6e22632');
foreach (array_merge($transients, $extra) as $var) {
${$var} = get_transient($var);
}
# flush options
$options = $wpdb->get_col("SELECT option_name FROM {$wpdb->options}");
foreach ($options as $option) {
if (!in_array($option, array_merge($transients, $extra))) {
if (preg_match("/^_transient_/", $option)) {
delete_option($option);
} else {
$this->delete($option, 'options');
}
}
}
$this->delete('notoptions', 'options');
$this->delete('alloptions', 'options');
unset($options);
# restore key transients
foreach ($transients as $var) {
if (${$var} !== false) {
set_transient($var, ${$var});
}
}
if ($feed_220431e2eb0959fa9c7fcb07c6e22632 !== false) {
$var = 'feed_220431e2eb0959fa9c7fcb07c6e22632';
set_transient($var, ${$var}, min(3600, cache_timeout));
$var = 'feed_mod_220431e2eb0959fa9c7fcb07c6e22632';
set_transient($var, time(), min(3600, cache_timeout));
}
return true;
}
/**
* Access this plugin’s working instance
*
* @wp-hook plugins_loaded
* @return object of this class
*/
public static function get_instance()
{
NULL === self::$instance and self::$instance = new self();
return self::$instance;
}
/**
* ob_callback()
*
* @param string $buffer
* @return string $buffer
**/
static function ob_callback($buffer)
{
if (!class_exists('sem_cache')) {
return $buffer;
}
if (DONOTCACHEPAGE) {
return $buffer;
}
# some things just shouldn't be cached
if (self::$nocache && !in_array(self::$status_code, array(301, 302, 404)) || !in_array(self::$status_code, array(200, 301, 302, 404))) {
return $buffer;
}
# sanity check on cookies
global $sem_cache_cookies;
if (!$sem_cache_cookies || $sem_cache_cookies != sem_cache::get_cookies()) {
return $buffer;
}
# only cache visitor requests
if (array_intersect(array_keys($_COOKIE), $sem_cache_cookies)) {
return $buffer;
}
# bail on valid but rarely served pages
if (self::$status_code == 200 && !(!is_feed() && is_singular() || !is_feed() && (is_home() || is_category()) && !is_paged() || is_feed() && (!is_archive() && !is_singular() || is_category()))) {
return $buffer;
}
#don't cache a contact form page due to spam prevention techniques
// if ( preg_match("/(\bsem_contact_form\b)/i",$buffer) )
// return $buffer;
#don't cache a page due if a sem_no_cache flag is found. Provide manual way to exclude a page
if (preg_match("/(\\bsem_do_not_cache\\b)/i", $buffer)) {
return $buffer;
}
$permalink_structure = get_option('permalink_structure');
# statically cache only when relevant
self::$static &= strpos($_SERVER['REQUEST_URI'], './') === false && self::$status_code == 200 && !is_feed() && empty($_GET) && $permalink_structure && strpos($permalink_structure, "|/index\\.php/|") === false;
# sanity check on the base folder
$host = get_option('home');
if (preg_match("|^([^/]+://[^/]+)/|", $host, $_host)) {
$host = end($_host);
}
if ($host != self::$host) {
return $buffer;
}
# sanity check on incomplete files
if (!in_array(self::$status_code, array(301, 302)) && !preg_match("/(?:<\\/html>|<\\/rss>|<\\/feed>)/i", $buffer)) {
return $buffer;
}
# sanity check on mobile users
global $sem_mobile_agents;
if ($sem_mobile_agents != sem_cache::get_mobile_agents()) {
return $buffer;
}
$mobile_agents = $sem_mobile_agents;
// $mobile_agents = array_map('preg_quote', (array) $mobile_agents);
$mobile_agents = implode("|", $mobile_agents);
if (preg_match("{({$mobile_agents})}i", $_SERVER['HTTP_USER_AGENT'])) {
return $buffer;
}
if (preg_match("/(?=.*?\\bandroid\\b)(?=.*?\\bmobile\\b).*\$/i", $_SERVER['HTTP_USER_AGENT'])) {
return $buffer;
}
// made it through all the checks. Let's minify the html now
// $buffer = self::minify_html( $buffer );
if (self::$static) {
$file = preg_replace("/#.*/", '', $_SERVER['REQUEST_URI']);
$file = '/static/' . trim($file, '/');
if (!preg_match("/\\.html\$/", $file)) {
global $wp_rewrite;
if ($wp_rewrite->use_trailing_slashes) {
$file = $file . '/index.html';
} else {
$file = $file . '.html';
}
}
cache_fs::put_contents($file, $buffer);
} elseif (self::$memory) {
$cache_id = $host . preg_replace("/#.*/", '', $_SERVER['REQUEST_URI']);
$cache_id = md5($cache_id);
$headers = headers_list();
if (self::$status_header) {
array_unshift($headers, self::$status_header);
}
wp_cache_add($cache_id, $headers, 'cached_headers', cache_timeout);
if ($buffer && !in_array(self::$status_code, array(301, 302))) {
wp_cache_add($cache_id, $buffer, 'cached_buffers', cache_timeout);
}
} elseif (!(function_exists('is_multisite') && is_multisite())) {
# poor man's memcached
$cache_id = $host . preg_replace("/#.*/", '', $_SERVER['REQUEST_URI']);
$cache_id = md5($cache_id);
$file = '/semi-static/' . $cache_id;
$headers = headers_list();
if (self::$status_header) {
array_unshift($headers, self::$status_header);
}
cache_fs::put_contents($file . '.meta', serialize($headers));
if ($buffer && !in_array(self::$status_code, array(301, 302))) {
cache_fs::put_contents($file . '.html', $buffer);
}
}
return $buffer;
}
/**
* disable_assets()
*
* @return void
**/
static function disable_assets()
{
update_site_option('asset_cache', 0);
sem_cache::flush_assets();
}