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<?php |
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|
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if (!defined('ABSPATH')) { |
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exit; |
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} |
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|
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/** |
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* Atomic state transitions for one asynchronous suggestion worker. |
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* |
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* The AJAX handler owns request validation and HTTP termination; this store |
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* owns the transient read/decide/write critical sections so those concerns |
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* cannot drift apart across claim, completion, and fatal-shutdown paths. |
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*/ |
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final class ABJ_404_Solution_SuggestionWorkerStateStore { |
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|
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public const OUTCOME_CLAIMED = 'claimed'; |
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public const OUTCOME_STALE = 'stale'; |
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public const OUTCOME_BUSY = 'busy'; |
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public const OUTCOME_WRITE_FAILED = 'write_failed'; |
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public const OUTCOME_STORED = 'stored'; |
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|
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/** @var ABJ_404_Solution_SynchronizationUtils */ |
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private $synchronizer; |
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|
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/** @var ABJ_404_Solution_Clock */ |
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private $clock; |
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|
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public function __construct( |
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ABJ_404_Solution_SynchronizationUtils $synchronizer, |
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ABJ_404_Solution_Clock $clock |
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) { |
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$this->synchronizer = $synchronizer; |
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$this->clock = $clock; |
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} |
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|
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/** |
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* @param array{transientKey: string, normalizedURL: string, token: string} $request |
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* @return array{status: string, startedAt: int} |
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*/ |
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public function claimWorker(array $request): array { |
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$lockKey = ABJ_404_Solution_SuggestionTransient::lockKeyForNormalizedUrl($request['normalizedURL']); |
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$owner = $this->synchronizer->synchronizerAcquireLockTry($lockKey); |
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if ($owner === '') { |
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return array('status' => self::OUTCOME_BUSY, 'startedAt' => 0); |
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} |
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|
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try { |
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$current = ABJ_404_Solution_SuggestionTransient::fromRaw(get_transient($request['transientKey'])); |
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if ($current === null || $current->isComplete() || $current->getToken() !== $request['token']) { |
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return array('status' => self::OUTCOME_STALE, 'startedAt' => 0); |
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} |
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$now = $this->clock->now(); |
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if ($current->isPending() && $current->isClaimed() && !$current->isWorkerStuck($now)) { |
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return array('status' => self::OUTCOME_STALE, 'startedAt' => 0); |
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} |
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|
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$createdAt = $current->getCreatedAt() > 0 ? $current->getCreatedAt() : $now; |
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$stored = set_transient( |
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$request['transientKey'], |
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ABJ_404_Solution_SuggestionTransient::pendingArray( |
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$current->getUrl(), |
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$request['token'], |
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$now, |
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$createdAt |
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), |
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ABJ_404_Solution_SuggestionTransient::PENDING_TTL_SECONDS |
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); |
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return array( |
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'status' => $stored ? self::OUTCOME_CLAIMED : self::OUTCOME_WRITE_FAILED, |
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'startedAt' => $stored ? $now : 0, |
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); |
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} finally { |
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$this->synchronizer->synchronizerReleaseLock($owner, $lockKey); |
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} |
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} |
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|
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/** |
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* @param array{transientKey: string, normalizedURL: string, requestedURL: string, token: string, workerStartedAt: int, suggestionsPacket: array<int, mixed>} $request |
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*/ |
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public function publishCompleted(array $request): string { |
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$lockKey = ABJ_404_Solution_SuggestionTransient::lockKeyForNormalizedUrl($request['normalizedURL']); |
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$owner = $this->synchronizer->synchronizerAcquireLockTry($lockKey); |
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if ($owner === '') { |
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return self::OUTCOME_BUSY; |
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} |
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|
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try { |
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$current = ABJ_404_Solution_SuggestionTransient::fromRaw(get_transient($request['transientKey'])); |
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if ($current === null || $current->isComplete() || $current->getToken() !== $request['token'] |
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|| $current->getStartedAt() !== $request['workerStartedAt'] |
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) { |
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return self::OUTCOME_STALE; |
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} |
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$stored = set_transient( |
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$request['transientKey'], |
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ABJ_404_Solution_SuggestionTransient::completeArray( |
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$request['requestedURL'], |
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$request['suggestionsPacket'], |
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$this->clock->now(), |
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$request['token'] |
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), |
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ABJ_404_Solution_SuggestionTransient::COMPLETE_TTL_SECONDS |
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); |
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return $stored ? self::OUTCOME_STORED : self::OUTCOME_WRITE_FAILED; |
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} finally { |
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$this->synchronizer->synchronizerReleaseLock($owner, $lockKey); |
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} |
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} |
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|
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/** |
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* @param array{transientKey: string, normalizedURL: string, token: string, workerStartedAt: int|null} $request |
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*/ |
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public function publishCrashMarker(array $request): string { |
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$lockKey = ABJ_404_Solution_SuggestionTransient::lockKeyForNormalizedUrl($request['normalizedURL']); |
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$owner = $this->synchronizer->synchronizerAcquireLockTry($lockKey); |
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if ($owner === '') { |
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return self::OUTCOME_BUSY; |
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} |
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|
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try { |
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$current = ABJ_404_Solution_SuggestionTransient::fromRaw(get_transient($request['transientKey'])); |
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if ($current === null || $current->isComplete() || $current->getToken() !== $request['token'] |
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|| ($request['workerStartedAt'] !== null |
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&& $current->getStartedAt() !== $request['workerStartedAt']) |
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) { |
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return self::OUTCOME_STALE; |
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} |
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$stored = set_transient( |
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$request['transientKey'], |
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ABJ_404_Solution_SuggestionTransient::errorArray($request['token']), |
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ABJ_404_Solution_SuggestionTransient::ERROR_TTL_SECONDS |
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); |
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return $stored ? self::OUTCOME_STORED : self::OUTCOME_WRITE_FAILED; |
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} finally { |
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$this->synchronizer->synchronizerReleaseLock($owner, $lockKey); |
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} |
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} |
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} |
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|
