weekly release 3.8dev
[moodle.git] / cache / locallib.php
CommitLineData
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1<?php
2// This file is part of Moodle - http://moodle.org/
3//
4// Moodle is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8//
9// Moodle is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with Moodle. If not, see <http://www.gnu.org/licenses/>.
16
17/**
18 * The supplementary cache API.
19 *
20 * This file is part of Moodle's cache API, affectionately called MUC.
21 * It contains elements of the API that are not required in order to use caching.
22 * Things in here are more in line with administration and management of the cache setup and configuration.
23 *
24 * @package core
25 * @category cache
26 * @copyright 2012 Sam Hemelryk
27 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
28 */
29
30defined('MOODLE_INTERNAL') || die();
31
32/**
33 * Cache configuration writer.
34 *
35 * This class should only be used when you need to write to the config, all read operations exist within the cache_config.
36 *
37 * @package core
38 * @category cache
39 * @copyright 2012 Sam Hemelryk
40 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
41 */
42class cache_config_writer extends cache_config {
43
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44 /**
45 * Switch that gets set to true when ever a cache_config_writer instance is saving the cache configuration file.
46 * If this is set to true when save is next called we must avoid the trying to save and instead return the
47 * generated config so that is may be used instead of the file.
48 * @var bool
49 */
50 protected static $creatingconfig = false;
51
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52 /**
53 * Returns an instance of the configuration writer.
54 *
55 * @return cache_config_writer
56 */
57 public static function instance() {
58 $factory = cache_factory::instance();
59 return $factory->create_config_instance(true);
60 }
61
62 /**
63 * Saves the current configuration.
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64 *
65 * Exceptions within this function are tolerated but must be of type cache_exception.
66 * They are caught during initialisation and written to the error log. This is required in order to avoid
67 * infinite loop situations caused by the cache throwing exceptions during its initialisation.
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68 */
69 protected function config_save() {
70 global $CFG;
79a8ea65 71 $cachefile = static::get_config_file_path();
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72 $directory = dirname($cachefile);
73 if ($directory !== $CFG->dataroot && !file_exists($directory)) {
74 $result = make_writable_directory($directory, false);
75 if (!$result) {
7383a7e2 76 throw new cache_exception('ex_configcannotsave', 'cache', '', null, 'Cannot create config directory. Check the permissions on your moodledata directory.');
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77 }
78 }
79 if (!file_exists($directory) || !is_writable($directory)) {
7383a7e2 80 throw new cache_exception('ex_configcannotsave', 'cache', '', null, 'Config directory is not writable. Check the permissions on the moodledata/muc directory.');
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81 }
82
83 // Prepare a configuration array to store.
7383a7e2 84 $configuration = $this->generate_configuration_array();
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85
86 // Prepare the file content.
87 $content = "<?php defined('MOODLE_INTERNAL') || die();\n \$configuration = ".var_export($configuration, true).";";
88
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89 // We need to create a temporary cache lock instance for use here. Remember we are generating the config file
90 // it doesn't exist and thus we can't use the normal API for this (it'll just try to use config).
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91 $lockconf = reset($this->configlocks);
92 if ($lockconf === false) {
93 debugging('Your cache configuration file is out of date and needs to be refreshed.', DEBUG_DEVELOPER);
94 // Use the default
95 $lockconf = array(
96 'name' => 'cachelock_file_default',
97 'type' => 'cachelock_file',
98 'dir' => 'filelocks',
99 'default' => true
100 );
101 }
34c84c72 102 $factory = cache_factory::instance();
573a6c8e 103 $locking = $factory->create_lock_instance($lockconf);
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104 if ($locking->lock('configwrite', 'config', true)) {
105 // Its safe to use w mode here because we have already acquired the lock.
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106 $handle = fopen($cachefile, 'w');
107 fwrite($handle, $content);
108 fflush($handle);
109 fclose($handle);
34c84c72 110 $locking->unlock('configwrite', 'config');
eb459f71 111 @chmod($cachefile, $CFG->filepermissions);
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112 // Tell PHP to recompile the script.
113 core_component::invalidate_opcode_php_cache($cachefile);
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114 } else {
115 throw new cache_exception('ex_configcannotsave', 'cache', '', null, 'Unable to open the cache config file.');
116 }
117 }
118
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119 /**
120 * Generates a configuration array suitable to be written to the config file.
121 * @return array
122 */
123 protected function generate_configuration_array() {
124 $configuration = array();
7866b094 125 $configuration['siteidentifier'] = $this->siteidentifier;
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126 $configuration['stores'] = $this->configstores;
127 $configuration['modemappings'] = $this->configmodemappings;
128 $configuration['definitions'] = $this->configdefinitions;
129 $configuration['definitionmappings'] = $this->configdefinitionmappings;
130 $configuration['locks'] = $this->configlocks;
131 return $configuration;
132 }
133
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134 /**
135 * Adds a plugin instance.
136 *
137 * This function also calls save so you should redirect immediately, or at least very shortly after
138 * calling this method.
139 *
140 * @param string $name The name for the instance (must be unique)
141 * @param string $plugin The name of the plugin.
142 * @param array $configuration The configuration data for the plugin instance.
143 * @return bool
144 * @throws cache_exception
145 */
26ce56fd 146 public function add_store_instance($name, $plugin, array $configuration = array()) {
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147 if (array_key_exists($name, $this->configstores)) {
148 throw new cache_exception('Duplicate name specificed for cache plugin instance. You must provide a unique name.');
149 }
6fec1820 150 $class = 'cachestore_'.$plugin;
8139ad13 151 if (!class_exists($class)) {
d0cac8b5 152 $plugins = core_component::get_plugin_list_with_file('cachestore', 'lib.php');
8139ad13 153 if (!array_key_exists($plugin, $plugins)) {
170f821b 154 throw new cache_exception('Invalid plugin name specified. The plugin does not exist or is not valid.');
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155 }
156 $file = $plugins[$plugin];
157 if (file_exists($file)) {
158 require_once($file);
159 }
160 if (!class_exists($class)) {
161 throw new cache_exception('Invalid cache plugin specified. The plugin does not contain the required class.');
162 }
163 }
d4797177 164 $reflection = new ReflectionClass($class);
75cde6b9 165 if (!$reflection->isSubclassOf('cache_store')) {
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166 throw new cache_exception('Invalid cache plugin specified. The plugin does not extend the required class.');
167 }
168 if (!$class::are_requirements_met()) {
169 throw new cache_exception('Unable to add new cache plugin instance. The requested plugin type is not supported.');
170 }
171 $this->configstores[$name] = array(
172 'name' => $name,
173 'plugin' => $plugin,
174 'configuration' => $configuration,
175 'features' => $class::get_supported_features($configuration),
176 'modes' => $class::get_supported_modes($configuration),
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177 'mappingsonly' => !empty($configuration['mappingsonly']),
178 'class' => $class,
179 'default' => false
8139ad13 180 );
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181 if (array_key_exists('lock', $configuration)) {
182 $this->configstores[$name]['lock'] = $configuration['lock'];
183 unset($this->configstores[$name]['configuration']['lock']);
184 }
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185 // Call instance_created()
186 $store = new $class($name, $this->configstores[$name]['configuration']);
187 $store->instance_created();
188
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189 $this->config_save();
190 return true;
191 }
192
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193 /**
194 * Adds a new lock instance to the config file.
195 *
196 * @param string $name The name the user gave the instance. PARAM_ALHPANUMEXT
197 * @param string $plugin The plugin we are creating an instance of.
198 * @param string $configuration Configuration data from the config instance.
199 * @throws cache_exception
200 */
201 public function add_lock_instance($name, $plugin, $configuration = array()) {
202 if (array_key_exists($name, $this->configlocks)) {
203 throw new cache_exception('Duplicate name specificed for cache lock instance. You must provide a unique name.');
204 }
205 $class = 'cachelock_'.$plugin;
206 if (!class_exists($class)) {
d0cac8b5 207 $plugins = core_component::get_plugin_list_with_file('cachelock', 'lib.php');
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208 if (!array_key_exists($plugin, $plugins)) {
209 throw new cache_exception('Invalid lock name specified. The plugin does not exist or is not valid.');
210 }
211 $file = $plugins[$plugin];
212 if (file_exists($file)) {
213 require_once($file);
214 }
215 if (!class_exists($class)) {
216 throw new cache_exception('Invalid lock plugin specified. The plugin does not contain the required class.');
217 }
218 }
219 $reflection = new ReflectionClass($class);
220 if (!$reflection->implementsInterface('cache_lock_interface')) {
221 throw new cache_exception('Invalid lock plugin specified. The plugin does not implement the required interface.');
222 }
223 $this->configlocks[$name] = array_merge($configuration, array(
224 'name' => $name,
225 'type' => 'cachelock_'.$plugin,
226 'default' => false
227 ));
228 $this->config_save();
229 }
230
231 /**
232 * Deletes a lock instance given its name.
233 *
234 * @param string $name The name of the plugin, PARAM_ALPHANUMEXT.
235 * @return bool
236 * @throws cache_exception
237 */
238 public function delete_lock_instance($name) {
239 if (!array_key_exists($name, $this->configlocks)) {
240 throw new cache_exception('The requested store does not exist.');
241 }
242 if ($this->configlocks[$name]['default']) {
243 throw new cache_exception('You can not delete the default lock.');
244 }
245 foreach ($this->configstores as $store) {
246 if (isset($store['lock']) && $store['lock'] === $name) {
247 throw new cache_exception('You cannot delete a cache lock that is being used by a store.');
248 }
249 }
250 unset($this->configlocks[$name]);
251 $this->config_save();
252 return true;
253 }
254
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255 /**
256 * Sets the mode mappings.
257 *
258 * These determine the default caches for the different modes.
259 * This function also calls save so you should redirect immediately, or at least very shortly after
260 * calling this method.
261 *
262 * @param array $modemappings
263 * @return bool
264 * @throws cache_exception
265 */
266 public function set_mode_mappings(array $modemappings) {
267 $mappings = array(
268 cache_store::MODE_APPLICATION => array(),
269 cache_store::MODE_SESSION => array(),
270 cache_store::MODE_REQUEST => array(),
271 );
272 foreach ($modemappings as $mode => $stores) {
273 if (!array_key_exists($mode, $mappings)) {
274 throw new cache_exception('The cache mode for the new mapping does not exist');
275 }
276 $sort = 0;
277 foreach ($stores as $store) {
278 if (!array_key_exists($store, $this->configstores)) {
279 throw new cache_exception('The instance name for the new mapping does not exist');
280 }
281 if (array_key_exists($store, $mappings[$mode])) {
282 throw new cache_exception('This cache mapping already exists');
283 }
284 $mappings[$mode][] = array(
285 'store' => $store,
286 'mode' => $mode,
287 'sort' => $sort++
288 );
289 }
290 }
291 $this->configmodemappings = array_merge(
292 $mappings[cache_store::MODE_APPLICATION],
293 $mappings[cache_store::MODE_SESSION],
294 $mappings[cache_store::MODE_REQUEST]
295 );
296
297 $this->config_save();
298 return true;
299 }
300
301 /**
302 * Edits a give plugin instance.
303 *
42f2c59e 304 * The plugin instance is determined by its name, hence you cannot rename plugins.
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305 * This function also calls save so you should redirect immediately, or at least very shortly after
306 * calling this method.
307 *
308 * @param string $name
309 * @param string $plugin
310 * @param array $configuration
311 * @return bool
312 * @throws cache_exception
313 */
26ce56fd 314 public function edit_store_instance($name, $plugin, $configuration) {
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315 if (!array_key_exists($name, $this->configstores)) {
316 throw new cache_exception('The requested instance does not exist.');
317 }
d0cac8b5 318 $plugins = core_component::get_plugin_list_with_file('cachestore', 'lib.php');
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319 if (!array_key_exists($plugin, $plugins)) {
320 throw new cache_exception('Invalid plugin name specified. The plugin either does not exist or is not valid.');
321 }
42f2c59e 322 $class = 'cachestore_'.$plugin;
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323 $file = $plugins[$plugin];
324 if (!class_exists($class)) {
325 if (file_exists($file)) {
326 require_once($file);
327 }
328 if (!class_exists($class)) {
42f2c59e 329 throw new cache_exception('Invalid cache plugin specified. The plugin does not contain the required class.'.$class);
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330 }
331 }
332 $this->configstores[$name] = array(
333 'name' => $name,
334 'plugin' => $plugin,
335 'configuration' => $configuration,
336 'features' => $class::get_supported_features($configuration),
337 'modes' => $class::get_supported_modes($configuration),
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338 'mappingsonly' => !empty($configuration['mappingsonly']),
339 'class' => $class,
340 'default' => $this->configstores[$name]['default'] // Can't change the default.
8139ad13 341 );
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342 if (array_key_exists('lock', $configuration)) {
343 $this->configstores[$name]['lock'] = $configuration['lock'];
344 unset($this->configstores[$name]['configuration']['lock']);
345 }
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346 $this->config_save();
347 return true;
348 }
349
350 /**
351 * Deletes a store instance.
352 *
353 * This function also calls save so you should redirect immediately, or at least very shortly after
354 * calling this method.
355 *
356 * @param string $name The name of the instance to delete.
357 * @return bool
358 * @throws cache_exception
359 */
26ce56fd 360 public function delete_store_instance($name) {
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361 if (!array_key_exists($name, $this->configstores)) {
362 throw new cache_exception('The requested store does not exist.');
363 }
364 if ($this->configstores[$name]['default']) {
365 throw new cache_exception('The can not delete the default stores.');
366 }
367 foreach ($this->configmodemappings as $mapping) {
368 if ($mapping['store'] === $name) {
369 throw new cache_exception('You cannot delete a cache store that has mode mappings.');
370 }
371 }
372 foreach ($this->configdefinitionmappings as $mapping) {
373 if ($mapping['store'] === $name) {
374 throw new cache_exception('You cannot delete a cache store that has definition mappings.');
375 }
376 }
a037c943 377
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378 // Call instance_deleted()
379 $class = 'cachestore_'.$this->configstores[$name]['plugin'];
380 $store = new $class($name, $this->configstores[$name]['configuration']);
381 $store->instance_deleted();
382
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383 unset($this->configstores[$name]);
384 $this->config_save();
385 return true;
386 }
387
388 /**
389 * Creates the default configuration and saves it.
390 *
391 * This function calls config_save, however it is safe to continue using it afterwards as this function should only ever
392 * be called when there is no configuration file already.
7383a7e2 393 *
b0dd08dd 394 * @param bool $forcesave If set to true then we will forcefully save the default configuration file.
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395 * @return true|array Returns true if the default configuration was successfully created.
396 * Returns a configuration array if it could not be saved. This is a bad situation. Check your error logs.
8139ad13 397 */
b0dd08dd 398 public static function create_default_configuration($forcesave = false) {
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399 // HACK ALERT.
400 // We probably need to come up with a better way to create the default stores, or at least ensure 100% that the
401 // default store plugins are protected from deletion.
8139ad13 402 $writer = new self;
fbf76dcd 403 $writer->configstores = self::get_default_stores();
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404 $writer->configdefinitions = self::locate_definitions();
405 $writer->configmodemappings = array(
406 array(
407 'mode' => cache_store::MODE_APPLICATION,
408 'store' => 'default_application',
409 'sort' => -1
410 ),
411 array(
412 'mode' => cache_store::MODE_SESSION,
413 'store' => 'default_session',
414 'sort' => -1
415 ),
416 array(
417 'mode' => cache_store::MODE_REQUEST,
418 'store' => 'default_request',
419 'sort' => -1
420 )
421 );
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422 $writer->configlocks = array(
423 'default_file_lock' => array(
167ad91e 424 'name' => 'cachelock_file_default',
34c84c72 425 'type' => 'cachelock_file',
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426 'dir' => 'filelocks',
427 'default' => true
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428 )
429 );
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430
431 $factory = cache_factory::instance();
432 // We expect the cache to be initialising presently. If its not then something has gone wrong and likely
433 // we are now in a loop.
b0dd08dd 434 if (!$forcesave && $factory->get_state() !== cache_factory::STATE_INITIALISING) {
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435 return $writer->generate_configuration_array();
436 }
437 $factory->set_state(cache_factory::STATE_SAVING);
8139ad13 438 $writer->config_save();
7383a7e2 439 return true;
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440 }
441
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442 /**
443 * Returns an array of default stores for use.
444 *
445 * @return array
446 */
447 protected static function get_default_stores() {
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448 global $CFG;
449
450 require_once($CFG->dirroot.'/cache/stores/file/lib.php');
451 require_once($CFG->dirroot.'/cache/stores/session/lib.php');
452 require_once($CFG->dirroot.'/cache/stores/static/lib.php');
453
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454 return array(
455 'default_application' => array(
456 'name' => 'default_application',
457 'plugin' => 'file',
458 'configuration' => array(),
459 'features' => cachestore_file::get_supported_features(),
460 'modes' => cachestore_file::get_supported_modes(),
461 'default' => true,
462 ),
463 'default_session' => array(
464 'name' => 'default_session',
465 'plugin' => 'session',
466 'configuration' => array(),
467 'features' => cachestore_session::get_supported_features(),
468 'modes' => cachestore_session::get_supported_modes(),
469 'default' => true,
470 ),
471 'default_request' => array(
472 'name' => 'default_request',
473 'plugin' => 'static',
474 'configuration' => array(),
475 'features' => cachestore_static::get_supported_features(),
476 'modes' => cachestore_static::get_supported_modes(),
477 'default' => true,
478 )
479 );
480 }
481
482 /**
483 * Updates the default stores within the MUC config file.
484 */
485 public static function update_default_config_stores() {
486 $factory = cache_factory::instance();
487 $factory->updating_started();
488 $config = $factory->create_config_instance(true);
489 $config->configstores = array_merge($config->configstores, self::get_default_stores());
490 $config->config_save();
491 $factory->updating_finished();
492 }
493
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494 /**
495 * Updates the definition in the configuration from those found in the cache files.
496 *
497 * Calls config_save further down, you should redirect immediately or asap after calling this method.
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498 *
499 * @param bool $coreonly If set to true only core definitions will be updated.
8139ad13 500 */
75af47ee 501 public static function update_definitions($coreonly = false) {
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502 $factory = cache_factory::instance();
503 $factory->updating_started();
504 $config = $factory->create_config_instance(true);
75af47ee 505 $config->write_definitions_to_cache(self::locate_definitions($coreonly));
9890ecfc 506 $factory->updating_finished();
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507 }
508
509 /**
510 * Locates all of the definition files.
511 *
75af47ee 512 * @param bool $coreonly If set to true only core definitions will be updated.
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513 * @return array
514 */
75af47ee 515 protected static function locate_definitions($coreonly = false) {
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516 global $CFG;
517
518 $files = array();
519 if (file_exists($CFG->dirroot.'/lib/db/caches.php')) {
520 $files['core'] = $CFG->dirroot.'/lib/db/caches.php';
521 }
522
75af47ee 523 if (!$coreonly) {
46f6f7f2 524 $plugintypes = core_component::get_plugin_types();
75af47ee 525 foreach ($plugintypes as $type => $location) {
d0cac8b5 526 $plugins = core_component::get_plugin_list_with_file($type, 'db/caches.php');
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527 foreach ($plugins as $plugin => $filepath) {
528 $component = clean_param($type.'_'.$plugin, PARAM_COMPONENT); // Standardised plugin name.
529 $files[$component] = $filepath;
530 }
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531 }
532 }
533
534 $definitions = array();
535 foreach ($files as $component => $file) {
536 $filedefs = self::load_caches_file($file);
537 foreach ($filedefs as $area => $definition) {
538 $area = clean_param($area, PARAM_AREA);
539 $id = $component.'/'.$area;
540 $definition['component'] = $component;
541 $definition['area'] = $area;
542 if (array_key_exists($id, $definitions)) {
d4797177 543 debugging('Error: duplicate cache definition found with id: '.$id, DEBUG_DEVELOPER);
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544 continue;
545 }
546 $definitions[$id] = $definition;
547 }
548 }
549
550 return $definitions;
551 }
552
553 /**
554 * Writes the updated definitions for the config file.
555 * @param array $definitions
556 */
557 private function write_definitions_to_cache(array $definitions) {
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558
559 // Preserve the selected sharing option when updating the definitions.
560 // This is set by the user and should never come from caches.php.
561 foreach ($definitions as $key => $definition) {
562 unset($definitions[$key]['selectedsharingoption']);
563 unset($definitions[$key]['userinputsharingkey']);
564 if (isset($this->configdefinitions[$key]) && isset($this->configdefinitions[$key]['selectedsharingoption'])) {
565 $definitions[$key]['selectedsharingoption'] = $this->configdefinitions[$key]['selectedsharingoption'];
566 }
567 if (isset($this->configdefinitions[$key]) && isset($this->configdefinitions[$key]['userinputsharingkey'])) {
568 $definitions[$key]['userinputsharingkey'] = $this->configdefinitions[$key]['userinputsharingkey'];
569 }
570 }
571
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572 $this->configdefinitions = $definitions;
573 foreach ($this->configdefinitionmappings as $key => $mapping) {
574 if (!array_key_exists($mapping['definition'], $definitions)) {
575 unset($this->configdefinitionmappings[$key]);
576 }
577 }
578 $this->config_save();
579 }
580
581 /**
582 * Loads the caches file if it exists.
583 * @param string $file Absolute path to the file.
584 * @return array
585 */
586 private static function load_caches_file($file) {
587 if (!file_exists($file)) {
588 return array();
589 }
590 $definitions = array();
170f821b 591 include($file);
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592 return $definitions;
593 }
594
595 /**
596 * Sets the mappings for a given definition.
597 *
598 * @param string $definition
599 * @param array $mappings
600 * @throws coding_exception
601 */
602 public function set_definition_mappings($definition, $mappings) {
603 if (!array_key_exists($definition, $this->configdefinitions)) {
604 throw new coding_exception('Invalid definition name passed when updating mappings.');
605 }
606 foreach ($mappings as $store) {
607 if (!array_key_exists($store, $this->configstores)) {
608 throw new coding_exception('Invalid store name passed when updating definition mappings.');
609 }
610 }
611 foreach ($this->configdefinitionmappings as $key => $mapping) {
612 if ($mapping['definition'] == $definition) {
613 unset($this->configdefinitionmappings[$key]);
614 }
615 }
616 $sort = count($mappings);
617 foreach ($mappings as $store) {
618 $this->configdefinitionmappings[] = array(
619 'store' => $store,
620 'definition' => $definition,
621 'sort' => $sort
622 );
623 $sort--;
624 }
625
626 $this->config_save();
627 }
628
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629 /**
630 * Update the site identifier stored by the cache API.
631 *
632 * @param string $siteidentifier
fe86ebfa 633 * @return string The new site identifier.
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634 */
635 public function update_site_identifier($siteidentifier) {
636 $this->siteidentifier = md5((string)$siteidentifier);
637 $this->config_save();
fe86ebfa 638 return $this->siteidentifier;
e0d9b7c0 639 }
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640
641 /**
642 * Sets the selected sharing options and key for a definition.
643 *
644 * @param string $definition The name of the definition to set for.
645 * @param int $sharingoption The sharing option to set.
646 * @param string|null $userinputsharingkey The user input key or null.
647 * @throws coding_exception
648 */
649 public function set_definition_sharing($definition, $sharingoption, $userinputsharingkey = null) {
650 if (!array_key_exists($definition, $this->configdefinitions)) {
651 throw new coding_exception('Invalid definition name passed when updating sharing options.');
652 }
653 if (!($this->configdefinitions[$definition]['sharingoptions'] & $sharingoption)) {
654 throw new coding_exception('Invalid sharing option passed when updating definition.');
655 }
656 $this->configdefinitions[$definition]['selectedsharingoption'] = (int)$sharingoption;
657 if (!empty($userinputsharingkey)) {
658 $this->configdefinitions[$definition]['userinputsharingkey'] = (string)$userinputsharingkey;
659 }
660 $this->config_save();
661 }
662
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663}
664
665/**
666 * A cache helper for administration tasks
667 *
668 * @package core
669 * @category cache
670 * @copyright 2012 Sam Hemelryk
671 * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
672 */
673abstract class cache_administration_helper extends cache_helper {
674
675 /**
676 * Returns an array containing all of the information about stores a renderer needs.
677 * @return array
678 */
26ce56fd 679 public static function get_store_instance_summaries() {
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680 $return = array();
681 $default = array();
682 $instance = cache_config::instance();
683 $stores = $instance->get_all_stores();
acf49f4b 684 $locks = $instance->get_locks();
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685 foreach ($stores as $name => $details) {
686 $class = $details['class'];
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687 $store = false;
688 if ($class::are_requirements_met()) {
689 $store = new $class($details['name'], $details['configuration']);
690 }
acf49f4b 691 $lock = (isset($details['lock'])) ? $locks[$details['lock']] : $instance->get_default_lock();
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692 $record = array(
693 'name' => $name,
694 'plugin' => $details['plugin'],
695 'default' => $details['default'],
f9599c77 696 'isready' => $store ? $store->is_ready() : false,
220f1cba 697 'requirementsmet' => $class::are_requirements_met(),
8139ad13 698 'mappings' => 0,
acf49f4b 699 'lock' => $lock,
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700 'modes' => array(
701 cache_store::MODE_APPLICATION =>
f9599c77 702 ($class::get_supported_modes($return) & cache_store::MODE_APPLICATION) == cache_store::MODE_APPLICATION,
8139ad13 703 cache_store::MODE_SESSION =>
f9599c77 704 ($class::get_supported_modes($return) & cache_store::MODE_SESSION) == cache_store::MODE_SESSION,
8139ad13 705 cache_store::MODE_REQUEST =>
f9599c77 706 ($class::get_supported_modes($return) & cache_store::MODE_REQUEST) == cache_store::MODE_REQUEST,
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707 ),
708 'supports' => array(
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709 'multipleidentifiers' => $store ? $store->supports_multiple_identifiers() : false,
710 'dataguarantee' => $store ? $store->supports_data_guarantee() : false,
711 'nativettl' => $store ? $store->supports_native_ttl() : false,
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712 'nativelocking' => ($store instanceof cache_is_lockable),
713 'keyawareness' => ($store instanceof cache_is_key_aware),
dbd2ea4e 714 'searchable' => ($store instanceof cache_is_searchable)
727c2173 715 ),
f9599c77 716 'warnings' => $store ? $store->get_warnings() : array()
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717 );
718 if (empty($details['default'])) {
719 $return[$name] = $record;
720 } else {
721 $default[$name] = $record;
722 }
723 }
724
725 ksort($return);
726 ksort($default);
727 $return = $return + $default;
728
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729 foreach ($instance->get_definition_mappings() as $mapping) {
730 if (!array_key_exists($mapping['store'], $return)) {
731 continue;
732 }
733 $return[$mapping['store']]['mappings']++;
734 }
735
736 return $return;
737 }
738
739 /**
740 * Returns an array of information about plugins, everything a renderer needs.
741 * @return array
742 */
26ce56fd 743 public static function get_store_plugin_summaries() {
8139ad13 744 $return = array();
d0cac8b5 745 $plugins = core_component::get_plugin_list_with_file('cachestore', 'lib.php', true);
8139ad13 746 foreach ($plugins as $plugin => $path) {
6fec1820 747 $class = 'cachestore_'.$plugin;
8139ad13 748 $return[$plugin] = array(
6fec1820 749 'name' => get_string('pluginname', 'cachestore_'.$plugin),
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750 'requirementsmet' => $class::are_requirements_met(),
751 'instances' => 0,
752 'modes' => array(
753 cache_store::MODE_APPLICATION => ($class::get_supported_modes() & cache_store::MODE_APPLICATION),
754 cache_store::MODE_SESSION => ($class::get_supported_modes() & cache_store::MODE_SESSION),
755 cache_store::MODE_REQUEST => ($class::get_supported_modes() & cache_store::MODE_REQUEST),
756 ),
757 'supports' => array(
758 'multipleidentifiers' => ($class::get_supported_features() & cache_store::SUPPORTS_MULTIPLE_IDENTIFIERS),
759 'dataguarantee' => ($class::get_supported_features() & cache_store::SUPPORTS_DATA_GUARANTEE),
760 'nativettl' => ($class::get_supported_features() & cache_store::SUPPORTS_NATIVE_TTL),
761 'nativelocking' => (in_array('cache_is_lockable', class_implements($class))),
762 'keyawareness' => (array_key_exists('cache_is_key_aware', class_implements($class))),
763 ),
7e7e108f 764 'canaddinstance' => ($class::can_add_instance() && $class::are_requirements_met())
8139ad13
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765 );
766 }
767
768 $instance = cache_config::instance();
769 $stores = $instance->get_all_stores();
770 foreach ($stores as $store) {
771 $plugin = $store['plugin'];
772 if (array_key_exists($plugin, $return)) {
773 $return[$plugin]['instances']++;
774 }
775 }
776
777 return $return;
778 }
779
780 /**
781 * Returns an array about the definitions. All the information a renderer needs.
782 * @return array
783 */
784 public static function get_definition_summaries() {
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785 $factory = cache_factory::instance();
786 $config = $factory->create_config_instance();
8139ad13 787 $storenames = array();
e28a9539 788 foreach ($config->get_all_stores() as $key => $store) {
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789 if (!empty($store['default'])) {
790 $storenames[$key] = new lang_string('store_'.$key, 'cache');
8139ad13 791 } else {
e28a9539 792 $storenames[$store['name']] = $store['name'];
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793 }
794 }
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795 /* @var cache_definition[] $definitions */
796 $definitions = array();
797 foreach ($config->get_definitions() as $key => $definition) {
798 $definitions[$key] = cache_definition::load($definition['component'].'/'.$definition['area'], $definition);
8139ad13 799 }
8139ad13 800 foreach ($definitions as $id => $definition) {
8139ad13 801 $mappings = array();
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802 foreach (cache_helper::get_stores_suitable_for_definition($definition) as $store) {
803 $mappings[] = $storenames[$store->my_name()];
8139ad13 804 }
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805 $return[$id] = array(
806 'id' => $id,
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807 'name' => $definition->get_name(),
808 'mode' => $definition->get_mode(),
809 'component' => $definition->get_component(),
810 'area' => $definition->get_area(),
46e17f04 811 'mappings' => $mappings,
4350192a 812 'canuselocalstore' => $definition->can_use_localstore(),
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813 'sharingoptions' => self::get_definition_sharing_options($definition->get_sharing_options(), false),
814 'selectedsharingoption' => self::get_definition_sharing_options($definition->get_selected_sharing_option(), true),
815 'userinputsharingkey' => $definition->get_user_input_sharing_key()
8139ad13
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816 );
817 }
818 return $return;
819 }
820
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821 /**
822 * Given a sharing option hash this function returns an array of strings that can be used to describe it.
823 *
824 * @param int $sharingoption The sharing option hash to get strings for.
825 * @param bool $isselectedoptions Set to true if the strings will be used to view the selected options.
826 * @return array An array of lang_string's.
827 */
828 public static function get_definition_sharing_options($sharingoption, $isselectedoptions = true) {
829 $options = array();
830 $prefix = ($isselectedoptions) ? 'sharingselected' : 'sharing';
831 if ($sharingoption & cache_definition::SHARING_ALL) {
832 $options[cache_definition::SHARING_ALL] = new lang_string($prefix.'_all', 'cache');
833 }
834 if ($sharingoption & cache_definition::SHARING_SITEID) {
835 $options[cache_definition::SHARING_SITEID] = new lang_string($prefix.'_siteid', 'cache');
836 }
837 if ($sharingoption & cache_definition::SHARING_VERSION) {
838 $options[cache_definition::SHARING_VERSION] = new lang_string($prefix.'_version', 'cache');
839 }
840 if ($sharingoption & cache_definition::SHARING_INPUT) {
841 $options[cache_definition::SHARING_INPUT] = new lang_string($prefix.'_input', 'cache');
842 }
843 return $options;
844 }
845
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846 /**
847 * Returns all of the actions that can be performed on a definition.
848 * @param context $context
849 * @return array
850 */
54519330 851 public static function get_definition_actions(context $context, array $definition) {
8139ad13 852 if (has_capability('moodle/site:config', $context)) {
54519330
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853 $actions = array();
854 // Edit mappings.
855 $actions[] = array(
856 'text' => get_string('editmappings', 'cache'),
857 'url' => new moodle_url('/cache/admin.php', array('action' => 'editdefinitionmapping', 'sesskey' => sesskey()))
858 );
859 // Edit sharing.
860 if (count($definition['sharingoptions']) > 1) {
861 $actions[] = array(
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862 'text' => get_string('editsharing', 'cache'),
863 'url' => new moodle_url('/cache/admin.php', array('action' => 'editdefinitionsharing', 'sesskey' => sesskey()))
54519330
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864 );
865 }
866 // Purge.
867 $actions[] = array(
868 'text' => get_string('purge', 'cache'),
869 'url' => new moodle_url('/cache/admin.php', array('action' => 'purgedefinition', 'sesskey' => sesskey()))
8139ad13 870 );
54519330 871 return $actions;
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872 }
873 return array();
874 }
875
876 /**
877 * Returns all of the actions that can be performed on a store.
878 *
879 * @param string $name The name of the store
880 * @param array $storedetails
881 * @return array
882 */
26ce56fd 883 public static function get_store_instance_actions($name, array $storedetails) {
8139ad13 884 $actions = array();
0601e0ee 885 if (has_capability('moodle/site:config', context_system::instance())) {
8139ad13
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886 $baseurl = new moodle_url('/cache/admin.php', array('store' => $name, 'sesskey' => sesskey()));
887 if (empty($storedetails['default'])) {
888 $actions[] = array(
889 'text' => get_string('editstore', 'cache'),
890 'url' => new moodle_url($baseurl, array('action' => 'editstore', 'plugin' => $storedetails['plugin']))
891 );
892 $actions[] = array(
893 'text' => get_string('deletestore', 'cache'),
894 'url' => new moodle_url($baseurl, array('action' => 'deletestore'))
895 );
896 }
897 $actions[] = array(
898 'text' => get_string('purge', 'cache'),
50523565 899 'url' => new moodle_url($baseurl, array('action' => 'purgestore'))
8139ad13
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900 );
901 }
902 return $actions;
903 }
904
905
906 /**
907 * Returns all of the actions that can be performed on a plugin.
908 *
909 * @param string $name The name of the plugin
910 * @param array $plugindetails
911 * @return array
912 */
26ce56fd 913 public static function get_store_plugin_actions($name, array $plugindetails) {
8139ad13 914 $actions = array();
7e7e108f 915 if (has_capability('moodle/site:config', context_system::instance())) {
8139ad13
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916 if (!empty($plugindetails['canaddinstance'])) {
917 $url = new moodle_url('/cache/admin.php', array('action' => 'addstore', 'plugin' => $name, 'sesskey' => sesskey()));
918 $actions[] = array(
919 'text' => get_string('addinstance', 'cache'),
920 'url' => $url
921 );
922 }
923 }
924 return $actions;
925 }
926
927 /**
928 * Returns a form that can be used to add a store instance.
929 *
930 * @param string $plugin The plugin to add an instance of
6fec1820 931 * @return cachestore_addinstance_form
8139ad13
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932 * @throws coding_exception
933 */
934 public static function get_add_store_form($plugin) {
170f821b 935 global $CFG; // Needed for includes.
bd3b3bba 936 $plugins = core_component::get_plugin_list('cachestore');
42f2c59e
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937 if (!array_key_exists($plugin, $plugins)) {
938 throw new coding_exception('Invalid cache plugin used when trying to create an edit form.');
939 }
940 $plugindir = $plugins[$plugin];
6fec1820 941 $class = 'cachestore_addinstance_form';
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942 if (file_exists($plugindir.'/addinstanceform.php')) {
943 require_once($plugindir.'/addinstanceform.php');
6fec1820
SH
944 if (class_exists('cachestore_'.$plugin.'_addinstance_form')) {
945 $class = 'cachestore_'.$plugin.'_addinstance_form';
946 if (!array_key_exists('cachestore_addinstance_form', class_parents($class))) {
947 throw new coding_exception('Cache plugin add instance forms must extend cachestore_addinstance_form');
8139ad13
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948 }
949 }
950 }
951
26ce56fd 952 $locks = self::get_possible_locks_for_stores($plugindir, $plugin);
167ad91e 953
8139ad13 954 $url = new moodle_url('/cache/admin.php', array('action' => 'addstore'));
167ad91e 955 return new $class($url, array('plugin' => $plugin, 'store' => null, 'locks' => $locks));
8139ad13
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956 }
957
958 /**
959 * Returns a form that can be used to edit a store instance.
960 *
961 * @param string $plugin
962 * @param string $store
6fec1820 963 * @return cachestore_addinstance_form
8139ad13
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964 * @throws coding_exception
965 */
966 public static function get_edit_store_form($plugin, $store) {
170f821b 967 global $CFG; // Needed for includes.
bd3b3bba 968 $plugins = core_component::get_plugin_list('cachestore');
42f2c59e
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969 if (!array_key_exists($plugin, $plugins)) {
970 throw new coding_exception('Invalid cache plugin used when trying to create an edit form.');
971 }
972 $factory = cache_factory::instance();
973 $config = $factory->create_config_instance();
974 $stores = $config->get_all_stores();
975 if (!array_key_exists($store, $stores)) {
976 throw new coding_exception('Invalid store name given when trying to create an edit form.');
977 }
978 $plugindir = $plugins[$plugin];
6fec1820 979 $class = 'cachestore_addinstance_form';
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980 if (file_exists($plugindir.'/addinstanceform.php')) {
981 require_once($plugindir.'/addinstanceform.php');
6fec1820
SH
982 if (class_exists('cachestore_'.$plugin.'_addinstance_form')) {
983 $class = 'cachestore_'.$plugin.'_addinstance_form';
984 if (!array_key_exists('cachestore_addinstance_form', class_parents($class))) {
985 throw new coding_exception('Cache plugin add instance forms must extend cachestore_addinstance_form');
8139ad13
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986 }
987 }
988 }
989
26ce56fd 990 $locks = self::get_possible_locks_for_stores($plugindir, $plugin);
42f2c59e 991
81ede547
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992 $url = new moodle_url('/cache/admin.php', array('action' => 'editstore', 'plugin' => $plugin, 'store' => $store));
993 $editform = new $class($url, array('plugin' => $plugin, 'store' => $store, 'locks' => $locks));
acf49f4b 994 if (isset($stores[$store]['lock'])) {
25927c42 995 $editform->set_data(array('lock' => $stores[$store]['lock']));
acf49f4b 996 }
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997 // See if the cachestore is going to want to load data for the form.
998 // If it has a customised add instance form then it is going to want to.
999 $storeclass = 'cachestore_'.$plugin;
1000 $storedata = $stores[$store];
2b274ad0 1001 if (array_key_exists('configuration', $storedata) && array_key_exists('cache_is_configurable', class_implements($storeclass))) {
81ede547
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1002 $storeclass::config_set_edit_form_data($editform, $storedata['configuration']);
1003 }
1004 return $editform;
42f2c59e
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1005 }
1006
1007 /**
1008 * Returns an array of suitable lock instances for use with this plugin, or false if the plugin handles locking itself.
1009 *
1010 * @param string $plugindir
1011 * @param string $plugin
1012 * @return array|false
1013 */
26ce56fd 1014 protected static function get_possible_locks_for_stores($plugindir, $plugin) {
42f2c59e
SH
1015 global $CFG; // Needed for includes.
1016 $supportsnativelocking = false;
1017 if (file_exists($plugindir.'/lib.php')) {
1018 require_once($plugindir.'/lib.php');
1019 $pluginclass = 'cachestore_'.$plugin;
1020 if (class_exists($pluginclass)) {
1021 $supportsnativelocking = array_key_exists('cache_is_lockable', class_implements($pluginclass));
1022 }
1023 }
1024
1025 if (!$supportsnativelocking) {
1026 $config = cache_config::instance();
1027 $locks = array();
1028 foreach ($config->get_locks() as $lock => $conf) {
1029 if (!empty($conf['default'])) {
1030 $name = get_string($lock, 'cache');
1031 } else {
1032 $name = $lock;
1033 }
1034 $locks[$lock] = $name;
1035 }
1036 } else {
1037 $locks = false;
1038 }
1039
1040 return $locks;
8139ad13
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1041 }
1042
1043 /**
1044 * Processes the results of the add/edit instance form data for a plugin returning an array of config information suitable to
1045 * store in configuration.
1046 *
1047 * @param stdClass $data The mform data.
1048 * @return array
1049 * @throws coding_exception
1050 */
1051 public static function get_store_configuration_from_data(stdClass $data) {
1052 global $CFG;
1053 $file = $CFG->dirroot.'/cache/stores/'.$data->plugin.'/lib.php';
1054 if (!file_exists($file)) {
1055 throw new coding_exception('Invalid cache plugin provided. '.$file);
1056 }
1057 require_once($file);
6fec1820 1058 $class = 'cachestore_'.$data->plugin;
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1059 if (!class_exists($class)) {
1060 throw new coding_exception('Invalid cache plugin provided.');
1061 }
2b274ad0
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1062 if (array_key_exists('cache_is_configurable', class_implements($class))) {
1063 return $class::config_get_configuration_array($data);
8139ad13
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1064 }
1065 return array();
1066 }
1067
1068 /**
1069 * Get an array of stores that are suitable to be used for a given definition.
1070 *
1071 * @param string $component
1072 * @param string $area
1073 * @return array Array containing 3 elements
1074 * 1. An array of currently used stores
1075 * 2. An array of suitable stores
1076 * 3. An array of default stores
1077 */
1078 public static function get_definition_store_options($component, $area) {
1079 $factory = cache_factory::instance();
1080 $definition = $factory->create_definition($component, $area);
1081 $config = cache_config::instance();
1082 $currentstores = $config->get_stores_for_definition($definition);
1083 $possiblestores = $config->get_stores($definition->get_mode(), $definition->get_requirements_bin());
1084
1085 $defaults = array();
1086 foreach ($currentstores as $key => $store) {
1087 if (!empty($store['default'])) {
1088 $defaults[] = $key;
1089 unset($currentstores[$key]);
1090 }
1091 }
1092 foreach ($possiblestores as $key => $store) {
167ad91e 1093 if ($store['default']) {
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1094 unset($possiblestores[$key]);
1095 $possiblestores[$key] = $store;
1096 }
1097 }
1098 return array($currentstores, $possiblestores, $defaults);
1099 }
1100
1101 /**
1102 * Get the default stores for all modes.
1103 *
1104 * @return array An array containing sub-arrays, one for each mode.
1105 */
1106 public static function get_default_mode_stores() {
d31fd615 1107 global $OUTPUT;
8139ad13 1108 $instance = cache_config::instance();
d31fd615
SH
1109 $adequatestores = cache_helper::get_stores_suitable_for_mode_default();
1110 $icon = new pix_icon('i/warning', new lang_string('inadequatestoreformapping', 'cache'));
8139ad13
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1111 $storenames = array();
1112 foreach ($instance->get_all_stores() as $key => $store) {
1113 if (!empty($store['default'])) {
1114 $storenames[$key] = new lang_string('store_'.$key, 'cache');
1115 }
1116 }
1117 $modemappings = array(
1118 cache_store::MODE_APPLICATION => array(),
1119 cache_store::MODE_SESSION => array(),
1120 cache_store::MODE_REQUEST => array(),
1121 );
1122 foreach ($instance->get_mode_mappings() as $mapping) {
1123 $mode = $mapping['mode'];
1124 if (!array_key_exists($mode, $modemappings)) {
1125 debugging('Unknown mode in cache store mode mappings', DEBUG_DEVELOPER);
1126 continue;
1127 }
1128 if (array_key_exists($mapping['store'], $storenames)) {
1129 $modemappings[$mode][$mapping['store']] = $storenames[$mapping['store']];
1130 } else {
1131 $modemappings[$mode][$mapping['store']] = $mapping['store'];
1132 }
d31fd615
SH
1133 if (!array_key_exists($mapping['store'], $adequatestores)) {
1134 $modemappings[$mode][$mapping['store']] = $modemappings[$mode][$mapping['store']].' '.$OUTPUT->render($icon);
1135 }
8139ad13
SH
1136 }
1137 return $modemappings;
1138 }
167ad91e
SH
1139
1140 /**
1141 * Returns an array summarising the locks available in the system
1142 */
1143 public static function get_lock_summaries() {
1144 $locks = array();
1145 $instance = cache_config::instance();
1146 $stores = $instance->get_all_stores();
1147 foreach ($instance->get_locks() as $lock) {
1148 $default = !empty($lock['default']);
1149 if ($default) {
1150 $name = new lang_string($lock['name'], 'cache');
1151 } else {
1152 $name = $lock['name'];
1153 }
1154 $uses = 0;
1155 foreach ($stores as $store) {
1156 if (!empty($store['lock']) && $store['lock'] === $lock['name']) {
1157 $uses++;
1158 }
1159 }
1160 $lockdata = array(
1161 'name' => $name,
1162 'default' => $default,
acf49f4b
SH
1163 'uses' => $uses,
1164 'type' => get_string('pluginname', $lock['type'])
167ad91e 1165 );
acf49f4b 1166 $locks[$lock['name']] = $lockdata;
167ad91e
SH
1167 }
1168 return $locks;
1169 }
acf49f4b
SH
1170
1171 /**
1172 * Returns an array of lock plugins for which we can add an instance.
1173 *
1174 * Suitable for use within an mform select element.
1175 *
1176 * @return array
1177 */
1178 public static function get_addable_lock_options() {
059e08ed 1179 $plugins = core_component::get_plugin_list_with_class('cachelock', '', 'lib.php');
acf49f4b
SH
1180 $options = array();
1181 $len = strlen('cachelock_');
1182 foreach ($plugins as $plugin => $class) {
1183 $method = "$class::can_add_instance";
1184 if (is_callable($method) && !call_user_func($method)) {
1185 // Can't add an instance of this plugin.
1186 continue;
1187 }
1188 $options[substr($plugin, $len)] = get_string('pluginname', $plugin);
1189 }
1190 return $options;
1191 }
1192
1193 /**
1194 * Gets the form to use when adding a lock instance.
1195 *
1196 * @param string $plugin
1197 * @param array $lockplugin
1198 * @return cache_lock_form
1199 * @throws coding_exception
1200 */
1201 public static function get_add_lock_form($plugin, array $lockplugin = null) {
1202 global $CFG; // Needed for includes.
bd3b3bba 1203 $plugins = core_component::get_plugin_list('cachelock');
acf49f4b
SH
1204 if (!array_key_exists($plugin, $plugins)) {
1205 throw new coding_exception('Invalid cache lock plugin requested when trying to create a form.');
1206 }
1207 $plugindir = $plugins[$plugin];
1208 $class = 'cache_lock_form';
1209 if (file_exists($plugindir.'/addinstanceform.php') && in_array('cache_is_configurable', class_implements($class))) {
1210 require_once($plugindir.'/addinstanceform.php');
1211 if (class_exists('cachelock_'.$plugin.'_addinstance_form')) {
1212 $class = 'cachelock_'.$plugin.'_addinstance_form';
1213 if (!array_key_exists('cache_lock_form', class_parents($class))) {
1214 throw new coding_exception('Cache lock plugin add instance forms must extend cache_lock_form');
1215 }
1216 }
1217 }
1218 return new $class(null, array('lock' => $plugin));
1219 }
1220
1221 /**
1222 * Gets configuration data from a new lock instance form.
1223 *
1224 * @param string $plugin
1225 * @param stdClass $data
1226 * @return array
1227 * @throws coding_exception
1228 */
1229 public static function get_lock_configuration_from_data($plugin, $data) {
1230 global $CFG;
1231 $file = $CFG->dirroot.'/cache/locks/'.$plugin.'/lib.php';
1232 if (!file_exists($file)) {
1233 throw new coding_exception('Invalid cache plugin provided. '.$file);
1234 }
1235 require_once($file);
1236 $class = 'cachelock_'.$plugin;
1237 if (!class_exists($class)) {
1238 throw new coding_exception('Invalid cache plugin provided.');
1239 }
1240 if (array_key_exists('cache_is_configurable', class_implements($class))) {
1241 return $class::config_get_configuration_array($data);
1242 }
1243 return array();
1244 }
7866b094 1245}