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| 1 | <?php |
| 2 | /** |
| 3 | * This program is free software; you can redistribute it and/or modify |
| 4 | * it under the terms of the GNU General Public License as published by |
| 5 | * the Free Software Foundation; either version 2 of the License, or |
| 6 | * (at your option) any later version. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License along |
| 14 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 15 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
| 16 | * http://www.gnu.org/copyleft/gpl.html |
| 17 | * |
| 18 | * @file |
| 19 | */ |
| 20 | |
| 21 | namespace MediaWiki\Storage; |
| 22 | |
| 23 | use BagOStuff; |
| 24 | use Content; |
| 25 | use Liuggio\StatsdClient\Factory\StatsdDataFactoryInterface; |
| 26 | use MediaWiki\HookContainer\HookContainer; |
| 27 | use MediaWiki\HookContainer\HookRunner; |
| 28 | use MediaWiki\Page\PageIdentity; |
| 29 | use MediaWiki\Page\WikiPageFactory; |
| 30 | use MediaWiki\Parser\ParserOutput; |
| 31 | use MediaWiki\Parser\ParserOutputFlags; |
| 32 | use MediaWiki\Revision\SlotRecord; |
| 33 | use MediaWiki\Storage\Hook\ParserOutputStashForEditHook; |
| 34 | use MediaWiki\User\UserEditTracker; |
| 35 | use MediaWiki\User\UserFactory; |
| 36 | use MediaWiki\User\UserIdentity; |
| 37 | use Psr\Log\LoggerInterface; |
| 38 | use stdClass; |
| 39 | use Wikimedia\Rdbms\IConnectionProvider; |
| 40 | use Wikimedia\ScopedCallback; |
| 41 | use WikiPage; |
| 42 | |
| 43 | /** |
| 44 | * Manage the pre-emptive page parsing for edits to wiki pages. |
| 45 | * |
| 46 | * This is written to by ApiStashEdit, and consumed by ApiEditPage |
| 47 | * and EditPage (via PageUpdaterFactory and DerivedPageDataUpdater). |
| 48 | * |
| 49 | * See also mediawiki.action.edit/stash.js. |
| 50 | * |
| 51 | * @since 1.34 |
| 52 | * @ingroup Page |
| 53 | */ |
| 54 | class PageEditStash { |
| 55 | /** @var BagOStuff */ |
| 56 | private $cache; |
| 57 | /** @var IConnectionProvider */ |
| 58 | private $dbProvider; |
| 59 | /** @var LoggerInterface */ |
| 60 | private $logger; |
| 61 | /** @var StatsdDataFactoryInterface */ |
| 62 | private $stats; |
| 63 | /** @var ParserOutputStashForEditHook */ |
| 64 | private $hookRunner; |
| 65 | /** @var UserEditTracker */ |
| 66 | private $userEditTracker; |
| 67 | /** @var UserFactory */ |
| 68 | private $userFactory; |
| 69 | /** @var WikiPageFactory */ |
| 70 | private $wikiPageFactory; |
| 71 | /** @var int */ |
| 72 | private $initiator; |
| 73 | |
| 74 | public const ERROR_NONE = 'stashed'; |
| 75 | public const ERROR_PARSE = 'error_parse'; |
| 76 | public const ERROR_CACHE = 'error_cache'; |
| 77 | public const ERROR_UNCACHEABLE = 'uncacheable'; |
| 78 | public const ERROR_BUSY = 'busy'; |
| 79 | |
| 80 | public const PRESUME_FRESH_TTL_SEC = 30; |
| 81 | public const MAX_CACHE_TTL = 300; // 5 minutes |
| 82 | public const MAX_SIGNATURE_TTL = 60; |
| 83 | |
| 84 | private const MAX_CACHE_RECENT = 2; |
| 85 | |
| 86 | public const INITIATOR_USER = 1; |
| 87 | public const INITIATOR_JOB_OR_CLI = 2; |
| 88 | |
| 89 | /** |
| 90 | * @param BagOStuff $cache |
| 91 | * @param IConnectionProvider $dbProvider |
| 92 | * @param LoggerInterface $logger |
| 93 | * @param StatsdDataFactoryInterface $stats |
| 94 | * @param UserEditTracker $userEditTracker |
| 95 | * @param UserFactory $userFactory |
| 96 | * @param WikiPageFactory $wikiPageFactory |
| 97 | * @param HookContainer $hookContainer |
| 98 | * @param int $initiator Class INITIATOR__* constant |
| 99 | */ |
| 100 | public function __construct( |
| 101 | BagOStuff $cache, |
| 102 | IConnectionProvider $dbProvider, |
| 103 | LoggerInterface $logger, |
| 104 | StatsdDataFactoryInterface $stats, |
| 105 | UserEditTracker $userEditTracker, |
| 106 | UserFactory $userFactory, |
| 107 | WikiPageFactory $wikiPageFactory, |
| 108 | HookContainer $hookContainer, |
| 109 | $initiator |
| 110 | ) { |
| 111 | $this->cache = $cache; |
| 112 | $this->dbProvider = $dbProvider; |
| 113 | $this->logger = $logger; |
| 114 | $this->stats = $stats; |
| 115 | $this->userEditTracker = $userEditTracker; |
| 116 | $this->userFactory = $userFactory; |
| 117 | $this->wikiPageFactory = $wikiPageFactory; |
| 118 | $this->hookRunner = new HookRunner( $hookContainer ); |
| 119 | $this->initiator = $initiator; |
| 120 | } |
| 121 | |
| 122 | /** |
| 123 | * @param PageUpdater $pageUpdater (a WikiPage instance is also supported but deprecated) |
| 124 | * @param Content $content Edit content |
| 125 | * @param UserIdentity $user |
| 126 | * @param string $summary Edit summary |
| 127 | * @return string Class ERROR_* constant |
| 128 | */ |
| 129 | public function parseAndCache( $pageUpdater, Content $content, UserIdentity $user, string $summary ) { |
| 130 | $logger = $this->logger; |
| 131 | |
| 132 | if ( $pageUpdater instanceof WikiPage ) { |
| 133 | wfDeprecated( __METHOD__ . ' with WikiPage instance', '1.42' ); |
| 134 | $pageUpdater = $pageUpdater->newPageUpdater( $user ); |
| 135 | } |
| 136 | |
| 137 | $page = $pageUpdater->getPage(); |
| 138 | $key = $this->getStashKey( $page, $this->getContentHash( $content ), $user ); |
| 139 | $fname = __METHOD__; |
| 140 | |
| 141 | // Use the primary DB to allow for fast blocking locks on the "save path" where this |
| 142 | // value might actually be used to complete a page edit. If the edit submission request |
| 143 | // happens before this edit stash requests finishes, then the submission will block until |
| 144 | // the stash request finishes parsing. For the lock acquisition below, there is not much |
| 145 | // need to duplicate parsing of the same content/user/summary bundle, so try to avoid |
| 146 | // blocking at all here. |
| 147 | $dbw = $this->dbProvider->getPrimaryDatabase(); |
| 148 | if ( !$dbw->lock( $key, $fname, 0 ) ) { |
| 149 | // De-duplicate requests on the same key |
| 150 | return self::ERROR_BUSY; |
| 151 | } |
| 152 | /** @noinspection PhpUnusedLocalVariableInspection */ |
| 153 | $unlocker = new ScopedCallback( static function () use ( $dbw, $key, $fname ) { |
| 154 | $dbw->unlock( $key, $fname ); |
| 155 | } ); |
| 156 | |
| 157 | $cutoffTime = time() - self::PRESUME_FRESH_TTL_SEC; |
| 158 | |
| 159 | // Reuse any freshly build matching edit stash cache |
| 160 | $editInfo = $this->getStashValue( $key ); |
| 161 | if ( $editInfo && (int)wfTimestamp( TS_UNIX, $editInfo->timestamp ) >= $cutoffTime ) { |
| 162 | $alreadyCached = true; |
| 163 | } else { |
| 164 | $pageUpdater->setContent( SlotRecord::MAIN, $content ); |
| 165 | |
| 166 | $update = $pageUpdater->prepareUpdate( EDIT_INTERNAL ); // applies pre-safe transform |
| 167 | $output = $update->getCanonicalParserOutput(); // causes content to be parsed |
| 168 | $output->setCacheTime( $update->getRevision()->getTimestamp() ); |
| 169 | |
| 170 | // emulate a cache value that kind of looks like a PreparedEdit, for use below |
| 171 | $editInfo = (object)[ |
| 172 | 'pstContent' => $update->getRawContent( SlotRecord::MAIN ), |
| 173 | 'output' => $output, |
| 174 | 'timestamp' => $output->getCacheTime() |
| 175 | ]; |
| 176 | |
| 177 | $alreadyCached = false; |
| 178 | } |
| 179 | |
| 180 | $logContext = [ 'cachekey' => $key, 'title' => (string)$page ]; |
| 181 | |
| 182 | if ( $editInfo->output ) { |
| 183 | // Let extensions add ParserOutput metadata or warm other caches |
| 184 | $legacyUser = $this->userFactory->newFromUserIdentity( $user ); |
| 185 | $legacyPage = $this->wikiPageFactory->newFromTitle( $page ); |
| 186 | $this->hookRunner->onParserOutputStashForEdit( |
| 187 | $legacyPage, $content, $editInfo->output, $summary, $legacyUser ); |
| 188 | |
| 189 | if ( $alreadyCached ) { |
| 190 | $logger->debug( "Parser output for key '{cachekey}' already cached.", $logContext ); |
| 191 | |
| 192 | return self::ERROR_NONE; |
| 193 | } |
| 194 | |
| 195 | $code = $this->storeStashValue( |
| 196 | $key, |
| 197 | $editInfo->pstContent, |
| 198 | $editInfo->output, |
| 199 | $editInfo->timestamp, |
| 200 | $user |
| 201 | ); |
| 202 | |
| 203 | if ( $code === true ) { |
| 204 | $logger->debug( "Cached parser output for key '{cachekey}'.", $logContext ); |
| 205 | |
| 206 | return self::ERROR_NONE; |
| 207 | } elseif ( $code === 'uncacheable' ) { |
| 208 | $logger->info( |
| 209 | "Uncacheable parser output for key '{cachekey}' [{code}].", |
| 210 | $logContext + [ 'code' => $code ] |
| 211 | ); |
| 212 | |
| 213 | return self::ERROR_UNCACHEABLE; |
| 214 | } else { |
| 215 | $logger->error( |
| 216 | "Failed to cache parser output for key '{cachekey}'.", |
| 217 | $logContext + [ 'code' => $code ] |
| 218 | ); |
| 219 | |
| 220 | return self::ERROR_CACHE; |
| 221 | } |
| 222 | } |
| 223 | |
| 224 | return self::ERROR_PARSE; |
| 225 | } |
| 226 | |
| 227 | /** |
| 228 | * Check that a prepared edit is in cache and still up-to-date |
| 229 | * |
| 230 | * This method blocks if the prepared edit is already being rendered, |
| 231 | * waiting until rendering finishes before doing final validity checks. |
| 232 | * |
| 233 | * The cache is rejected if template or file changes are detected. |
| 234 | * Note that foreign template or file transclusions are not checked. |
| 235 | * |
| 236 | * This returns an object with the following fields: |
| 237 | * - pstContent: the Content after pre-save-transform |
| 238 | * - output: the ParserOutput instance |
| 239 | * - timestamp: the timestamp of the parse |
| 240 | * - edits: author edit count if they are logged in or NULL otherwise |
| 241 | * |
| 242 | * @param PageIdentity $page |
| 243 | * @param Content $content |
| 244 | * @param UserIdentity $user to get parser options from |
| 245 | * @return stdClass|false Returns edit stash object or false on cache miss |
| 246 | */ |
| 247 | public function checkCache( PageIdentity $page, Content $content, UserIdentity $user ) { |
| 248 | $legacyUser = $this->userFactory->newFromUserIdentity( $user ); |
| 249 | if ( |
| 250 | // The context is not an HTTP POST request |
| 251 | !$legacyUser->getRequest()->wasPosted() || |
| 252 | // The context is a CLI script or a job runner HTTP POST request |
| 253 | $this->initiator !== self::INITIATOR_USER || |
| 254 | // The editor account is a known bot |
| 255 | $legacyUser->isBot() |
| 256 | ) { |
| 257 | // Avoid wasted queries and statsd pollution |
| 258 | return false; |
| 259 | } |
| 260 | |
| 261 | $logger = $this->logger; |
| 262 | |
| 263 | $key = $this->getStashKey( $page, $this->getContentHash( $content ), $user ); |
| 264 | $logContext = [ |
| 265 | 'key' => $key, |
| 266 | 'title' => (string)$page, |
| 267 | 'user' => $user->getName() |
| 268 | ]; |
| 269 | |
| 270 | $editInfo = $this->getAndWaitForStashValue( $key ); |
| 271 | if ( !is_object( $editInfo ) || !$editInfo->output ) { |
| 272 | $this->incrStatsByContent( 'cache_misses.no_stash', $content ); |
| 273 | if ( $this->recentStashEntryCount( $user ) > 0 ) { |
| 274 | $logger->info( "Empty cache for key '{key}' but not for user.", $logContext ); |
| 275 | } else { |
| 276 | $logger->debug( "Empty cache for key '{key}'.", $logContext ); |
| 277 | } |
| 278 | |
| 279 | return false; |
| 280 | } |
| 281 | |
| 282 | $age = time() - (int)wfTimestamp( TS_UNIX, $editInfo->output->getCacheTime() ); |
| 283 | $logContext['age'] = $age; |
| 284 | |
| 285 | $isCacheUsable = true; |
| 286 | if ( $age <= self::PRESUME_FRESH_TTL_SEC ) { |
| 287 | // Assume nothing changed in this time |
| 288 | $this->incrStatsByContent( 'cache_hits.presumed_fresh', $content ); |
| 289 | $logger->debug( "Timestamp-based cache hit for key '{key}'.", $logContext ); |
| 290 | } elseif ( !$user->isRegistered() ) { |
| 291 | $lastEdit = $this->lastEditTime( $user ); |
| 292 | $cacheTime = $editInfo->output->getCacheTime(); |
| 293 | if ( $lastEdit < $cacheTime ) { |
| 294 | // Logged-out user made no local upload/template edits in the meantime |
| 295 | $this->incrStatsByContent( 'cache_hits.presumed_fresh', $content ); |
| 296 | $logger->debug( "Edit check based cache hit for key '{key}'.", $logContext ); |
| 297 | } else { |
| 298 | $isCacheUsable = false; |
| 299 | $this->incrStatsByContent( 'cache_misses.proven_stale', $content ); |
| 300 | $logger->info( "Stale cache for key '{key}' due to outside edits.", $logContext ); |
| 301 | } |
| 302 | } else { |
| 303 | if ( $editInfo->edits === $this->userEditTracker->getUserEditCount( $user ) ) { |
| 304 | // Logged-in user made no local upload/template edits in the meantime |
| 305 | $this->incrStatsByContent( 'cache_hits.presumed_fresh', $content ); |
| 306 | $logger->debug( "Edit count based cache hit for key '{key}'.", $logContext ); |
| 307 | } else { |
| 308 | $isCacheUsable = false; |
| 309 | $this->incrStatsByContent( 'cache_misses.proven_stale', $content ); |
| 310 | $logger->info( "Stale cache for key '{key}'due to outside edits.", $logContext ); |
| 311 | } |
| 312 | } |
| 313 | |
| 314 | if ( !$isCacheUsable ) { |
| 315 | return false; |
| 316 | } |
| 317 | |
| 318 | if ( $editInfo->output->getOutputFlag( ParserOutputFlags::VARY_REVISION ) ) { |
| 319 | // This can be used for the initial parse, e.g. for filters or doUserEditContent(), |
| 320 | // but a second parse will be triggered in doEditUpdates() no matter what |
| 321 | $logger->info( |
| 322 | "Cache for key '{key}' has vary-revision; post-insertion parse inevitable.", |
| 323 | $logContext |
| 324 | ); |
| 325 | } else { |
| 326 | static $flagsMaybeReparse = [ |
| 327 | // Similar to the above if we didn't guess the ID correctly |
| 328 | ParserOutputFlags::VARY_REVISION_ID, |
| 329 | // Similar to the above if we didn't guess the timestamp correctly |
| 330 | ParserOutputFlags::VARY_REVISION_TIMESTAMP, |
| 331 | // Similar to the above if we didn't guess the content correctly |
| 332 | ParserOutputFlags::VARY_REVISION_SHA1, |
| 333 | // Similar to the above if we didn't guess page ID correctly |
| 334 | ParserOutputFlags::VARY_PAGE_ID, |
| 335 | ]; |
| 336 | foreach ( $flagsMaybeReparse as $flag ) { |
| 337 | if ( $editInfo->output->getOutputFlag( $flag ) ) { |
| 338 | $logger->debug( |
| 339 | "Cache for key '{key}' has $flag; post-insertion parse possible.", |
| 340 | $logContext |
| 341 | ); |
| 342 | } |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | return $editInfo; |
| 347 | } |
| 348 | |
| 349 | /** |
| 350 | * @param string $subkey |
| 351 | * @param Content $content |
| 352 | */ |
| 353 | private function incrStatsByContent( $subkey, Content $content ) { |
| 354 | $this->stats->increment( 'editstash.' . $subkey ); // overall for b/c |
| 355 | $this->stats->increment( 'editstash_by_model.' . $content->getModel() . '.' . $subkey ); |
| 356 | } |
| 357 | |
| 358 | /** |
| 359 | * @param string $key |
| 360 | * @return bool|stdClass |
| 361 | */ |
| 362 | private function getAndWaitForStashValue( $key ) { |
| 363 | $editInfo = $this->getStashValue( $key ); |
| 364 | |
| 365 | if ( !$editInfo ) { |
| 366 | $start = microtime( true ); |
| 367 | // We ignore user aborts and keep parsing. Block on any prior parsing |
| 368 | // so as to use its results and make use of the time spent parsing. |
| 369 | $dbw = $this->dbProvider->getPrimaryDatabase(); |
| 370 | if ( $dbw->lock( $key, __METHOD__, 30 ) ) { |
| 371 | $editInfo = $this->getStashValue( $key ); |
| 372 | $dbw->unlock( $key, __METHOD__ ); |
| 373 | } |
| 374 | |
| 375 | $timeMs = 1000 * max( 0, microtime( true ) - $start ); |
| 376 | $this->stats->timing( 'editstash.lock_wait_time', $timeMs ); |
| 377 | } |
| 378 | |
| 379 | return $editInfo; |
| 380 | } |
| 381 | |
| 382 | /** |
| 383 | * @param string $textHash |
| 384 | * @return string|bool Text or false if missing |
| 385 | */ |
| 386 | public function fetchInputText( $textHash ) { |
| 387 | $textKey = $this->cache->makeKey( 'stashedit', 'text', $textHash ); |
| 388 | |
| 389 | return $this->cache->get( $textKey ); |
| 390 | } |
| 391 | |
| 392 | /** |
| 393 | * @param string $text |
| 394 | * @param string $textHash |
| 395 | * @return bool Success |
| 396 | */ |
| 397 | public function stashInputText( $text, $textHash ) { |
| 398 | $textKey = $this->cache->makeKey( 'stashedit', 'text', $textHash ); |
| 399 | |
| 400 | return $this->cache->set( |
| 401 | $textKey, |
| 402 | $text, |
| 403 | self::MAX_CACHE_TTL, |
| 404 | BagOStuff::WRITE_ALLOW_SEGMENTS |
| 405 | ); |
| 406 | } |
| 407 | |
| 408 | /** |
| 409 | * @param UserIdentity $user |
| 410 | * @return string|null TS_MW timestamp or null |
| 411 | */ |
| 412 | private function lastEditTime( UserIdentity $user ) { |
| 413 | $time = $this->dbProvider->getReplicaDatabase()->newSelectQueryBuilder() |
| 414 | ->select( 'MAX(rc_timestamp)' ) |
| 415 | ->from( 'recentchanges' ) |
| 416 | ->join( 'actor', null, 'actor_id=rc_actor' ) |
| 417 | ->where( [ 'actor_name' => $user->getName() ] ) |
| 418 | ->caller( __METHOD__ ) |
| 419 | ->fetchField(); |
| 420 | |
| 421 | return wfTimestampOrNull( TS_MW, $time ); |
| 422 | } |
| 423 | |
| 424 | /** |
| 425 | * Get hash of the content, factoring in model/format |
| 426 | * |
| 427 | * @param Content $content |
| 428 | * @return string |
| 429 | */ |
| 430 | private function getContentHash( Content $content ) { |
| 431 | return sha1( implode( "\n", [ |
| 432 | $content->getModel(), |
| 433 | $content->getDefaultFormat(), |
| 434 | $content->serialize( $content->getDefaultFormat() ) |
| 435 | ] ) ); |
| 436 | } |
| 437 | |
| 438 | /** |
| 439 | * Get the temporary prepared edit stash key for a user |
| 440 | * |
| 441 | * This key can be used for caching prepared edits provided: |
| 442 | * - a) The $user was used for PST options |
| 443 | * - b) The parser output was made from the PST using cannonical matching options |
| 444 | * |
| 445 | * @param PageIdentity $page |
| 446 | * @param string $contentHash Result of getContentHash() |
| 447 | * @param UserIdentity $user User to get parser options from |
| 448 | * @return string |
| 449 | */ |
| 450 | private function getStashKey( PageIdentity $page, $contentHash, UserIdentity $user ) { |
| 451 | return $this->cache->makeKey( |
| 452 | 'stashedit-info-v2', |
| 453 | md5( "{$page->getNamespace()}\n{$page->getDBkey()}" ), |
| 454 | // Account for the edit model/text |
| 455 | $contentHash, |
| 456 | // Account for user name related variables like signatures |
| 457 | md5( "{$user->getId()}\n{$user->getName()}" ) |
| 458 | ); |
| 459 | } |
| 460 | |
| 461 | /** |
| 462 | * @param string $key |
| 463 | * @return stdClass|bool Object map (pstContent,output,outputID,timestamp,edits) or false |
| 464 | */ |
| 465 | private function getStashValue( $key ) { |
| 466 | $serial = $this->cache->get( $key ); |
| 467 | |
| 468 | return $this->unserializeStashInfo( $serial ); |
| 469 | } |
| 470 | |
| 471 | /** |
| 472 | * Build a value to store in memcached based on the PST content and parser output |
| 473 | * |
| 474 | * This makes a simple version of WikiPage::prepareContentForEdit() as stash info |
| 475 | * |
| 476 | * @param string $key |
| 477 | * @param Content $pstContent Pre-Save transformed content |
| 478 | * @param ParserOutput $parserOutput |
| 479 | * @param string $timestamp TS_MW |
| 480 | * @param UserIdentity $user |
| 481 | * @return string|bool True or an error code |
| 482 | */ |
| 483 | private function storeStashValue( |
| 484 | $key, |
| 485 | Content $pstContent, |
| 486 | ParserOutput $parserOutput, |
| 487 | $timestamp, |
| 488 | UserIdentity $user |
| 489 | ) { |
| 490 | // If an item is renewed, mind the cache TTL determined by config and parser functions. |
| 491 | // Put an upper limit on the TTL to avoid extreme template/file staleness. |
| 492 | $age = time() - (int)wfTimestamp( TS_UNIX, $parserOutput->getCacheTime() ); |
| 493 | $ttl = min( $parserOutput->getCacheExpiry() - $age, self::MAX_CACHE_TTL ); |
| 494 | // Avoid extremely stale user signature timestamps (T84843) |
| 495 | if ( $parserOutput->getOutputFlag( ParserOutputFlags::USER_SIGNATURE ) ) { |
| 496 | $ttl = min( $ttl, self::MAX_SIGNATURE_TTL ); |
| 497 | } |
| 498 | |
| 499 | if ( $ttl <= 0 ) { |
| 500 | return 'uncacheable'; // low TTL due to a tag, magic word, or signature? |
| 501 | } |
| 502 | |
| 503 | // Store what is actually needed and split the output into another key (T204742) |
| 504 | $stashInfo = (object)[ |
| 505 | 'pstContent' => $pstContent, |
| 506 | 'output' => $parserOutput, |
| 507 | 'timestamp' => $timestamp, |
| 508 | 'edits' => $this->userEditTracker->getUserEditCount( $user ), |
| 509 | ]; |
| 510 | $serial = $this->serializeStashInfo( $stashInfo ); |
| 511 | if ( $serial === false ) { |
| 512 | return 'store_error'; |
| 513 | } |
| 514 | |
| 515 | $ok = $this->cache->set( $key, $serial, $ttl, BagOStuff::WRITE_ALLOW_SEGMENTS ); |
| 516 | if ( $ok ) { |
| 517 | // These blobs can waste slots in low cardinality memcached slabs |
| 518 | $this->pruneExcessStashedEntries( $user, $key ); |
| 519 | } |
| 520 | |
| 521 | return $ok ? true : 'store_error'; |
| 522 | } |
| 523 | |
| 524 | /** |
| 525 | * @param UserIdentity $user |
| 526 | * @param string $newKey |
| 527 | */ |
| 528 | private function pruneExcessStashedEntries( UserIdentity $user, $newKey ) { |
| 529 | $key = $this->cache->makeKey( 'stash-edit-recent', sha1( $user->getName() ) ); |
| 530 | |
| 531 | $keyList = $this->cache->get( $key ) ?: []; |
| 532 | if ( count( $keyList ) >= self::MAX_CACHE_RECENT ) { |
| 533 | $oldestKey = array_shift( $keyList ); |
| 534 | $this->cache->delete( $oldestKey, BagOStuff::WRITE_PRUNE_SEGMENTS ); |
| 535 | } |
| 536 | |
| 537 | $keyList[] = $newKey; |
| 538 | $this->cache->set( $key, $keyList, 2 * self::MAX_CACHE_TTL ); |
| 539 | } |
| 540 | |
| 541 | /** |
| 542 | * @param UserIdentity $user |
| 543 | * @return int |
| 544 | */ |
| 545 | private function recentStashEntryCount( UserIdentity $user ) { |
| 546 | $key = $this->cache->makeKey( 'stash-edit-recent', sha1( $user->getName() ) ); |
| 547 | |
| 548 | return count( $this->cache->get( $key ) ?: [] ); |
| 549 | } |
| 550 | |
| 551 | private function serializeStashInfo( stdClass $stashInfo ) { |
| 552 | // @todo: use JSON with ParserOutput and Content |
| 553 | return serialize( $stashInfo ); |
| 554 | } |
| 555 | |
| 556 | private function unserializeStashInfo( $serial ) { |
| 557 | if ( is_string( $serial ) ) { |
| 558 | // @todo: use JSON with ParserOutput and Content |
| 559 | $stashInfo = unserialize( $serial ); |
| 560 | if ( is_object( $stashInfo ) && $stashInfo->output instanceof ParserOutput ) { |
| 561 | return $stashInfo; |
| 562 | } |
| 563 | } |
| 564 | |
| 565 | return false; |
| 566 | } |
| 567 | } |