class-foogallery-cache.php — Photo Gallery by FooGallery : Responsive Image Gallery, Masonry Gallery & Carousel trunk

foogallery / includes / class-foogallery-cache.php

foogallery / includes Last commit date

class-foogallery-cache.php

250 lines

1	<?php
2	/**
3	* Class used to cache gallery HTML output to save requests to the database
4	* Date: 20/03/2017
5	*/
6	if ( ! class_exists( 'FooGallery_Cache' ) ) {
7
8	class FooGallery_Cache {
9
10	function __construct() {
11	if ( is_admin() ) {
12	//intercept the gallery save and save the html output to post meta
13	add_action( 'foogallery_after_save_gallery', array( $this, 'cache_gallery_html_output_after_save' ), 10, 2 );
14
15	//add some settings to allow the clearing and disabling of the cache
16	add_filter( 'foogallery_admin_settings_override', array( $this, 'add_cache_settings' ) );
17
18	//render the clear HTML cache button
19	add_action( 'foogallery_admin_settings_custom_type_render_setting', array( $this, 'render_settings' ) );
20
21	// Ajax call for clearing HTML cache
22	add_action( 'wp_ajax_foogallery_clear_html_cache', array( $this, 'ajax_clear_all_caches' ) );
23
24	add_action( 'foogallery_admin_new_version_detected', array( $this, 'clear_cache_on_update' ) );
25
26	//clear the gallery caches when settings are updated or reset
27	add_action( 'foogallery_settings_updated', array( $this, 'clear_all_gallery_caches' ) );
28	add_action( 'foogallery_settings_reset', array( $this, 'clear_all_gallery_caches' ) );
29	}
30
31	add_filter( 'foogallery_load_gallery_template', array( $this, 'fetch_gallery_html_from_cache' ), 10, 3 );
32
33	add_filter( 'foogallery_html_cache_disabled', array( $this, 'disable_html_cache' ), 10, 3 );
34
35	add_filter( 'foogallery_render_template_clear_globals' , array( $this, 'render_template_clear_globals' ) );
36	}
37
38	/**
39	* Override if the gallery html cache is disabled
40	*
41	* @param $disabled bool
42	* @param $gallery FooGallery
43	* @return bool
44	*/
45	function disable_html_cache( $disabled, $gallery ) {
46
47	//check if the gallery sorting is random
48	if ( 'rand' === $gallery->sorting ) {
49	$disabled = true;
50	}
51
52	return $disabled;
53	}
54
55	/**
56	* Save the HTML output of the gallery after the gallery has been saved
57	*
58	* @param $post_id
59	* @param $form_post
60	*/
61	function cache_gallery_html_output_after_save( $post_id, $form_post ) {
62	$this->cache_gallery_html_output( $post_id );
63	}
64
65	/**
66	* Save the HTML output of the gallery to post meta so that it can be used in future requests
67	*
68	* @param $foogallery_id
69	*/
70	function cache_gallery_html_output( $foogallery_id ) {
71	$caching_enabled = $this->is_caching_enabled();
72
73	//check if caching is disabled and quit early
74	if ( !$caching_enabled ) {
75	return;
76	}
77
78	//we need a way to force the gallery to render it's output every time it is saved
79	global $foogallery_force_gallery_cache;
80	$foogallery_force_gallery_cache = true;
81
82	//capture the html output
83	ob_start();
84	foogallery_render_gallery( $foogallery_id );
85	$gallery_html = ob_get_contents();
86	ob_end_clean();
87
88	if ( $caching_enabled ) {
89	//save the output to post meta for later use
90	update_post_meta( $foogallery_id, FOOGALLERY_META_CACHE, $gallery_html );
91	}
92
93	$foogallery_force_gallery_cache = false;
94	}
95
96	function is_caching_enabled() {
97	global $current_foogallery_arguments;
98
99	//do some checks if we are using arguments
100	if ( isset( $current_foogallery_arguments ) ) {
101
102	//never cache if showing a preview
103	if ( array_key_exists( 'preview', $current_foogallery_arguments ) &&
104	true === $current_foogallery_arguments['preview'] ) {
105	return false;
106	}
107
108	//never cache if we are passing in extra arguments via the shortcode
109	$array_keys = array_keys( $current_foogallery_arguments );
110	if ( $array_keys != array( 'id', 'gallery' ) ) {
111	return false;
112	}
113	}
114
115	//next, check the settings
116	if ( 'on' === foogallery_get_setting( 'enable_html_cache' ) ) {
117	return true;
118	}
119
120	return false;
121	}
122
123	/**
124	* Override the template output
125	*
126	* @param $override
127	* @param $gallery
128	* @param $template_location
129	*
130	* @return bool
131	*/
132	function fetch_gallery_html_from_cache( $override, $gallery, $template_location ) {
133	global $foogallery_force_gallery_cache;
134	if ( $foogallery_force_gallery_cache ) {
135	return false;
136	}
137
138	//check if caching is disabled and quit early
139	if ( !$this->is_caching_enabled() ) {
140	return false;
141	}
142
143	//allow extensions of others disable the html cache
144	if ( apply_filters( 'foogallery_html_cache_disabled', false, $gallery ) ) {
145	return false;
146	}
147
148	$gallery_cache = get_post_meta( $gallery->ID, FOOGALLERY_META_CACHE, true );
149
150	if ( !empty( $gallery_cache ) && is_string( $gallery_cache ) ) {
151	//output the cached gallery html
152	echo $gallery_cache; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- Cached HTML output
153	return true; //return that we will override
154	} else {
155	//we should cache the result for next time
156	$this->cache_gallery_html_output( $gallery->ID );
157	}
158
159	return false;
160	}
161
162	/**
163	* Add some caching settings
164	* @param $settings
165	*
166	* @return array
167	*/
168	function add_cache_settings( $settings ) {
169
170	$cache_settings[] = array(
171	'id' => 'enable_html_cache',
172	'title' => __( 'Enable HTML Cache', 'foogallery' ),
173	'desc' => __( 'The gallery HTML that is generated can be cached. This can reduce the number of calls to the database when displaying a gallery and can increase site performance.', 'foogallery' ),
174	'type' => 'checkbox',
175	'tab' => 'general',
176	'section' => __( 'Performance', 'foogallery' )
177	);
178
179	$cache_settings[] = array(
180	'id' => 'clear_html_cache',
181	'title' => __( 'Clear HTML Cache', 'foogallery' ),
182	'desc' => __( 'If you enable the HTML cache, then you can use this button to clear the gallery HTML that has been cached for all galleries.', 'foogallery' ),
183	'type' => 'clear_gallery_cache_button',
184	'tab' => 'general',
185	'section' => __( 'Performance', 'foogallery' )
186	);
187
188	$new_settings = array_merge( $cache_settings, $settings['settings'] );
189
190	$settings['settings'] = $new_settings;
191
192	return $settings;
193	}
194
195	/**
196	* Render any custom setting types to the settings page
197	*/
198	function render_settings( $args ) {
199	if ('clear_gallery_cache_button' === $args['type'] ) { ?>
200	<div id="foogallery_clear_html_cache_container">
201	<input type="button" data-nonce="<?php echo esc_attr( wp_create_nonce( 'foogallery_clear_html_cache' ) ); ?>" class="button-primary foogallery_clear_html_cache" value="<?php esc_attr_e( 'Clear Gallery HTML Cache', 'foogallery' ); ?>">
202	<span id="foogallery_clear_html_cache_spinner" style="position: absolute" class="spinner"></span>
203	</div>
204	<?php }
205	}
206
207	/**
208	* AJAX endpoint for clearing all gallery caches
209	*/
210	function ajax_clear_all_caches() {
211	if ( check_admin_referer( 'foogallery_clear_html_cache' ) ) {
212
213	$this->clear_all_gallery_caches();
214
215	esc_html_e('The cache for all galleries has been cleared!', 'foogallery' );
216	die();
217	}
218	}
219
220	/**
221	* Clears all caches for all galleries
222	*/
223	function clear_all_gallery_caches() {
224	delete_post_meta_by_key( FOOGALLERY_META_CACHE );
225	}
226
227	/**
228	* Clear all caches when the plugin has been updated. This is to account for changes in the HTML when a new version is released.
229	*/
230	function clear_cache_on_update() {
231	$this->clear_all_gallery_caches();
232	}
233
234	/**
235	* Determine if the globals should be cleared when rendering a gallery
236	*
237	* @param $clear
238	*
239	* @return bool
240	*/
241	function render_template_clear_globals( $clear ) {
242	global $foogallery_force_gallery_cache;
243	if ( $foogallery_force_gallery_cache ) {
244	return false;
245	}
246
247	return $clear;
248	}
249	}
250	}