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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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* How many bytes of an admin-table response actually REACHED the browser. |
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* |
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* The exact mirror of ABJ_404_Solution_EncodedTableResponseSize, which answers |
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* the same question about the other end of the same response: that class says |
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* how many bytes the server encoded, this one says how many the browser |
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* measured arriving. Two modules rather than one because the two numbers come |
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* from different subsystems, different record kinds and different journals' |
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* worth of assumptions, and because either can be present without the other -- |
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* which is the whole finding when they disagree. Joining them is |
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* ABJ_404_Solution_ResponseBodyDeliveryEvidence's job, not this class's. |
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* |
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* Read ONLY from Resource Timing's `decodedBodySize`, never from the client |
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* report's own `bytes` field. That field is `responseText.length`, a UTF-16 |
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* CHARACTER count, and the table payload carries URLs that are not guaranteed |
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* ASCII -- comparing a character count against the server's octet count would |
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* manufacture a rewritten-in-transit verdict out of an accented redirect. |
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* `rt` is also the first field the client trims out of an oversized report |
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* (view_updater_transport_telemetry_delivery.js TRIM_FIELD_ORDER), so its |
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* absence is ordinary and stays a named absence rather than a number. |
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*/ |
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final class ABJ_404_Solution_DeliveredTableResponseSize { |
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|
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/** |
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* What the browser said one table request weighed, or a named absence. |
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* |
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* Pure: it takes journal lines rather than reading them, so a report with |
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* no timing entry, a trimmed report, and a report about a different |
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* attempt are all directly assertable. |
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* |
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* The attempt a report is ABOUT is resolved through |
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* ABJ_404_Solution_DiagnosticClientVerdict, the one extractor that already |
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* maps a browser report to the journal key its attempt was recorded under. |
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* Deriving a second keying here is exactly the defect that made the |
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* browser's verdicts land on orphan placeholder groups for a whole |
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* release. |
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* |
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* @param array<int, string> $lines Checkpoint JSONL lines, oldest first. |
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* @param string $requestId Normalized ledger id of the table attempt. |
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* @return array{bytes: int|null, source: string, resource_timing_state: string} |
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*/ |
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public static function forRequest(array $lines, string $requestId): array { |
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$result = array( |
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'bytes' => null, |
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'source' => ABJ_404_Solution_MeasuredBodyBytes::SOURCE_UNAVAILABLE, |
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'resource_timing_state' => ABJ_404_Solution_MeasuredBodyBytes::SOURCE_UNAVAILABLE, |
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); |
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if ($requestId === '') { |
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return $result; |
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} |
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foreach ($lines as $line) { |
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// Lines that cannot possibly match are rejected before the JSON |
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// decoder sees them: this pass runs over whole journals. |
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if (strpos($line, ABJ_404_Solution_DiagnosticClientVerdict::PRIOR_ATTEMPT_EVENT) === false) { |
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continue; |
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} |
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$record = json_decode($line, true); |
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if (!is_array($record) |
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|| ABJ_404_Solution_DiagnosticClientVerdict::reportedOutcome($record)['id'] !== $requestId) { |
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continue; |
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} |
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// Latest report wins: a retried attempt is reported more than once |
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// and the later report describes the later delivery. |
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$report = is_array($record['report'] ?? null) ? $record['report'] : array(); |
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$timing = is_array($report['rt'] ?? null) ? $report['rt'] : array(); |
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$bytes = ABJ_404_Solution_MeasuredBodyBytes::disclosed($timing['decodedBodySize'] ?? null); |
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$state = $report['rtState'] ?? null; |
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$result = array( |
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'bytes' => $bytes, |
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'source' => $bytes === null ? ABJ_404_Solution_MeasuredBodyBytes::SOURCE_UNAVAILABLE : ABJ_404_Solution_MeasuredBodyBytes::SOURCE_RESOURCE_TIMING, |
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'resource_timing_state' => is_scalar($state) |
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? (string)$state : ABJ_404_Solution_MeasuredBodyBytes::SOURCE_UNAVAILABLE, |
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); |
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} |
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return $result; |
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} |
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|
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} |
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|
