+global\FixBug20757::execute()

Complexity

Conditions	23
Paths	4

Size

Total Lines	212
Code Lines	134

Duplication

Lines	0
Ratio	0 %

Importance

Changes

0

<?php
	function execute() {
		$dbr = $this->getDB( DB_REPLICA );
		$dbw = $this->getDB( DB_MASTER );

		$dryRun = $this->getOption( 'dry-run' );
		if ( $dryRun ) {
			print "Dry run only.\n";
		}

		$startId = $this->getOption( 'start', 0 );
		$numGood = 0;
		$numFixed = 0;
		$numBad = 0;

		$totalRevs = $dbr->selectField( 'text', 'MAX(old_id)', false, __METHOD__ );

		// In MySQL 4.1+, the binary field old_text has a non-working LOWER() function
		$lowerLeft = 'LOWER(CONVERT(LEFT(old_text,22) USING latin1))';

		while ( true ) {
			print "ID: $startId / $totalRevs\r";

			$res = $dbr->select(
				'text',
				[ 'old_id', 'old_flags', 'old_text' ],
				[
					'old_id > ' . intval( $startId ),
					'old_flags LIKE \'%object%\' AND old_flags NOT LIKE \'%external%\'',
					"$lowerLeft = 'o:15:\"historyblobstub\"'",
				],
				__METHOD__,
				[
					'ORDER BY' => 'old_id',
					'LIMIT' => $this->batchSize,
				]
			);

			if ( !$res->numRows() ) {
				break;
			}

			$secondaryIds = [];
			$stubs = [];

			foreach ( $res as $row ) {
				$startId = $row->old_id;

				// Basic sanity checks
				$obj = unserialize( $row->old_text );
				if ( $obj === false ) {
					print "{$row->old_id}: unrecoverable: cannot unserialize\n";
					++$numBad;
					continue;
				}

				if ( !is_object( $obj ) ) {
					print "{$row->old_id}: unrecoverable: unserialized to type " .
						gettype( $obj ) . ", possible double-serialization\n";
					++$numBad;
					continue;
				}

				if ( strtolower( get_class( $obj ) ) !== 'historyblobstub' ) {
					print "{$row->old_id}: unrecoverable: unexpected object class " .
						get_class( $obj ) . "\n";
					++$numBad;
					continue;
				}

				// Process flags
				$flags = explode( ',', $row->old_flags );
				if ( in_array( 'utf-8', $flags ) || in_array( 'utf8', $flags ) ) {
					$legacyEncoding = false;
				} else {
					$legacyEncoding = true;
				}

				// Queue the stub for future batch processing
				$id = intval( $obj->mOldId );
				$secondaryIds[] = $id;
				$stubs[$row->old_id] = [
					'legacyEncoding' => $legacyEncoding,
					'secondaryId' => $id,
					'hash' => $obj->mHash,
				];
			}

			$secondaryIds = array_unique( $secondaryIds );

			if ( !count( $secondaryIds ) ) {
				continue;
			}

			// Run the batch query on blob_tracking
			$res = $dbr->select(
				'blob_tracking',
				'*',
				[
					'bt_text_id' => $secondaryIds,
				],
				__METHOD__
			);
			$trackedBlobs = [];
			foreach ( $res as $row ) {
				$trackedBlobs[$row->bt_text_id] = $row;
			}

			// Process the stubs
			foreach ( $stubs as $primaryId => $stub ) {
				$secondaryId = $stub['secondaryId'];
				if ( !isset( $trackedBlobs[$secondaryId] ) ) {
					// No tracked blob. Work out what went wrong
					$secondaryRow = $dbr->selectRow(
						'text',
						[ 'old_flags', 'old_text' ],
						[ 'old_id' => $secondaryId ],
						__METHOD__
					);
					if ( !$secondaryRow ) {
						print "$primaryId: unrecoverable: secondary row is missing\n";
						++$numBad;
					} elseif ( $this->isUnbrokenStub( $stub, $secondaryRow ) ) {
						// Not broken yet, and not in the tracked clusters so it won't get
						// broken by the current RCT run.
						++$numGood;
					} elseif ( strpos( $secondaryRow->old_flags, 'external' ) !== false ) {
						print "$primaryId: unrecoverable: secondary gone to {$secondaryRow->old_text}\n";
						++$numBad;
					} else {
						print "$primaryId: unrecoverable: miscellaneous corruption of secondary row\n";
						++$numBad;
					}
					unset( $stubs[$primaryId] );
					continue;
				}
				$trackRow = $trackedBlobs[$secondaryId];

				// Check that the specified text really is available in the tracked source row
				$url = "DB://{$trackRow->bt_cluster}/{$trackRow->bt_blob_id}/{$stub['hash']}";
				$text = ExternalStore::fetchFromURL( $url );
				if ( $text === false ) {
					print "$primaryId: unrecoverable: source text missing\n";
					++$numBad;
					unset( $stubs[$primaryId] );
					continue;
				}
				if ( md5( $text ) !== $stub['hash'] ) {
					print "$primaryId: unrecoverable: content hashes do not match\n";
					++$numBad;
					unset( $stubs[$primaryId] );
					continue;
				}

				// Find the page_id and rev_id
				// The page is probably the same as the page of the secondary row
				$pageId = intval( $trackRow->bt_page );
				if ( !$pageId ) {
					$revId = $pageId = 0;
				} else {
					$revId = $this->findTextIdInPage( $pageId, $primaryId );
					if ( !$revId ) {
						// Actually an orphan
						$pageId = $revId = 0;
					}
				}

				$newFlags = $stub['legacyEncoding'] ? 'external' : 'external,utf-8';

				if ( !$dryRun ) {
					// Reset the text row to point to the original copy
					$this->beginTransaction( $dbw, __METHOD__ );

It seems like $dbw defined by $this->getDB(DB_MASTER) on line 46 can be null; however, Maintenance::beginTransaction() does not accept null, maybe add an additional type check?

					$dbw->update(
						'text',
						// SET
						[
							'old_flags' => $newFlags,
							'old_text' => $url
						],
						// WHERE
						[ 'old_id' => $primaryId ],
						__METHOD__
					);

					// Add a blob_tracking row so that the new reference can be recompressed
					// without needing to run trackBlobs.php again
					$dbw->insert( 'blob_tracking',
						[
							'bt_page' => $pageId,
							'bt_rev_id' => $revId,
							'bt_text_id' => $primaryId,
							'bt_cluster' => $trackRow->bt_cluster,
							'bt_blob_id' => $trackRow->bt_blob_id,
							'bt_cgz_hash' => $stub['hash'],
							'bt_new_url' => null,
							'bt_moved' => 0,
						],
						__METHOD__
					);
					$this->commitTransaction( $dbw, __METHOD__ );

It seems like $dbw defined by $this->getDB(DB_MASTER) on line 46 can be null; however, Maintenance::commitTransaction() does not accept null, maybe add an additional type check?

					$this->waitForSlaves();
				}

				print "$primaryId: resolved to $url\n";
				++$numFixed;
			}
		}

		print "\n";
		print "Fixed: $numFixed\n";
		print "Unrecoverable: $numBad\n";
		print "Good stubs: $numGood\n";
	}