/** @var int[] Prior flags member variable values */
private $priorFlags = [];
- /** @var mixed Class name or object With profileIn/profileOut methods */
+ /** @var callable|null */
protected $profiler;
/** @var TransactionProfiler */
protected $trxProfiler;
$this->srvCache = $params['srvCache'] ?? new HashBagOStuff();
- $this->profiler = $params['profiler'];
+ $this->profiler = is_callable( $params['profiler'] ) ? $params['profiler'] : null;
$this->trxProfiler = $params['trxProfiler'];
$this->connLogger = $params['connLogger'];
$this->queryLogger = $params['queryLogger'];
* used to adjust lock timeouts or encoding modes and the like.
* - connLogger: Optional PSR-3 logger interface instance.
* - queryLogger: Optional PSR-3 logger interface instance.
- * - profiler: Optional class name or object with profileIn()/profileOut() methods.
- * These will be called in query(), using a simplified version of the SQL that also
- * includes the agent as a SQL comment.
+ * - profiler : Optional callback that takes a section name argument and returns
+ * a ScopedCallback instance that ends the profile section in its destructor.
+ * These will be called in query(), using a simplified version of the SQL that
+ * also includes the agent as a SQL comment.
* - trxProfiler: Optional TransactionProfiler instance.
* - errorLogger: Optional callback that takes an Exception and logs it.
* - deprecationLogger: Optional callback that takes a string and logs it.
final public function close() {
$exception = null; // error to throw after disconnecting
+ $wasOpen = $this->opened;
+ // This should mostly do nothing if the connection is already closed
if ( $this->conn ) {
// Roll back any dangling transaction first
if ( $this->trxLevel ) {
// Close the actual connection in the binding handle
$closed = $this->closeConnection();
- $this->conn = false;
} else {
$closed = true; // already closed; nothing to do
}
+ $this->conn = false;
$this->opened = false;
// Throw any unexpected errors after having disconnected
throw $exception;
}
- // Sanity check that no callbacks are dangling
- $fnames = $this->pendingWriteAndCallbackCallers();
- if ( $fnames ) {
- throw new RuntimeException(
- "Transaction callbacks are still pending:\n" . implode( ', ', $fnames )
- );
+ // Note that various subclasses call close() at the start of open(), which itself is
+ // called by replaceLostConnection(). In that case, just because onTransactionResolution()
+ // callbacks are pending does not mean that an exception should be thrown. Rather, they
+ // will be executed after the reconnection step.
+ if ( $wasOpen ) {
+ // Sanity check that no callbacks are dangling
+ $fnames = $this->pendingWriteAndCallbackCallers();
+ if ( $fnames ) {
+ throw new RuntimeException(
+ "Transaction callbacks are still pending:\n" . implode( ', ', $fnames )
+ );
+ }
}
return $closed;
}
/**
- * Make sure isOpen() returns true as a sanity check
+ * Make sure there is an open connection handle (alive or not) as a sanity check
+ *
+ * This guards against fatal errors to the binding handle not being defined
+ * in cases where open() was never called or close() was already called
*
* @throws DBUnexpectedError
*/
- protected function assertOpen() {
+ protected function assertHasConnectionHandle() {
if ( !$this->isOpen() ) {
throw new DBUnexpectedError( $this, "DB connection was already closed." );
}
}
+ /**
+ * Make sure that this server is not marked as a replica nor read-only as a sanity check
+ *
+ * @throws DBUnexpectedError
+ */
+ protected function assertIsWritableMaster() {
+ if ( $this->getLBInfo( 'replica' ) === true ) {
+ throw new DBUnexpectedError(
+ $this,
+ 'Write operations are not allowed on replica database connections.'
+ );
+ }
+ $reason = $this->getReadOnlyReason();
+ if ( $reason !== false ) {
+ throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
+ }
+ }
+
/**
* Closes underlying database connection
* @since 1.20
public function query( $sql, $fname = __METHOD__, $tempIgnore = false ) {
$this->assertTransactionStatus( $sql, $fname );
+ $this->assertHasConnectionHandle();
- # Avoid fatals if close() was called
- $this->assertOpen();
-
+ $priorTransaction = $this->trxLevel;
$priorWritesPending = $this->writesOrCallbacksPending();
$this->lastQuery = $sql;
- $isWrite = $this->isWriteQuery( $sql );
- if ( $isWrite ) {
- $isNonTempWrite = !$this->registerTempTableOperation( $sql );
- } else {
- $isNonTempWrite = false;
- }
-
- if ( $isWrite ) {
- if ( $this->getLBInfo( 'replica' ) === true ) {
- throw new DBError(
- $this,
- 'Write operations are not allowed on replica database connections.'
- );
- }
+ if ( $this->isWriteQuery( $sql ) ) {
# In theory, non-persistent writes are allowed in read-only mode, but due to things
# like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
- $reason = $this->getReadOnlyReason();
- if ( $reason !== false ) {
- throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
- }
- # Set a flag indicating that writes have been done
- $this->lastWriteTime = microtime( true );
+ $this->assertIsWritableMaster();
+ # Avoid treating temporary table operations as meaningful "writes"
+ $isEffectiveWrite = !$this->registerTempTableOperation( $sql );
+ } else {
+ $isEffectiveWrite = false;
}
# Add trace comment to the begin of the sql string, right after the operator.
# Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
$commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
- # Start implicit transactions that wrap the request if DBO_TRX is enabled
- if ( !$this->trxLevel && $this->getFlag( self::DBO_TRX )
- && $this->isTransactableQuery( $sql )
- ) {
- $this->begin( __METHOD__ . " ($fname)", self::TRANSACTION_INTERNAL );
- $this->trxAutomatic = true;
- }
-
- # Keep track of whether the transaction has write queries pending
- if ( $this->trxLevel && !$this->trxDoneWrites && $isWrite ) {
- $this->trxDoneWrites = true;
- $this->trxProfiler->transactionWritingIn(
- $this->server, $this->getDomainID(), $this->trxShortId );
- }
-
- if ( $this->getFlag( self::DBO_DEBUG ) ) {
- $this->queryLogger->debug( "{$this->getDomainID()} {$commentedSql}" );
- }
-
# Send the query to the server and fetch any corresponding errors
- $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
+ $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
$lastError = $this->lastError();
$lastErrno = $this->lastErrno();
- # Try reconnecting if the connection was lost
+ $recoverableSR = false; // recoverable statement rollback?
+ $recoverableCL = false; // recoverable connection loss?
+
if ( $ret === false && $this->wasConnectionLoss() ) {
- # Check if any meaningful session state was lost
- $recoverable = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
+ # Check if no meaningful session state was lost
+ $recoverableCL = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
# Update session state tracking and try to restore the connection
$reconnected = $this->replaceLostConnection( __METHOD__ );
# Silently resend the query to the server if it is safe and possible
- if ( $reconnected && $recoverable ) {
- $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
+ if ( $recoverableCL && $reconnected ) {
+ $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
$lastError = $this->lastError();
$lastErrno = $this->lastErrno();
if ( $ret === false && $this->wasConnectionLoss() ) {
# Query probably causes disconnects; reconnect and do not re-run it
$this->replaceLostConnection( __METHOD__ );
+ } else {
+ $recoverableCL = false; // connection does not need recovering
+ $recoverableSR = $this->wasKnownStatementRollbackError();
}
}
+ } else {
+ $recoverableSR = $this->wasKnownStatementRollbackError();
}
if ( $ret === false ) {
- if ( $this->trxLevel ) {
- if ( $this->wasKnownStatementRollbackError() ) {
+ if ( $priorTransaction ) {
+ if ( $recoverableSR ) {
# We're ignoring an error that caused just the current query to be aborted.
# But log the cause so we can log a deprecation notice if a caller actually
# does ignore it.
$this->trxStatusIgnoredCause = [ $lastError, $lastErrno, $fname ];
- } else {
+ } elseif ( !$recoverableCL ) {
# Either the query was aborted or all queries after BEGIN where aborted.
# In the first case, the only options going forward are (a) ROLLBACK, or
# (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
# option is ROLLBACK, since the snapshots would have been released.
$this->trxStatus = self::STATUS_TRX_ERROR;
$this->trxStatusCause =
- $this->makeQueryException( $lastError, $lastErrno, $sql, $fname );
+ $this->getQueryExceptionAndLog( $lastError, $lastErrno, $sql, $fname );
$tempIgnore = false; // cannot recover
$this->trxStatusIgnoredCause = null;
}
*
* @param string $sql Original SQL query
* @param string $commentedSql SQL query with debugging/trace comment
- * @param bool $isWrite Whether the query is a (non-temporary) write operation
+ * @param bool $isEffectiveWrite Whether the query is a (non-temporary table) write
* @param string $fname Name of the calling function
* @return bool|ResultWrapper True for a successful write query, ResultWrapper
* object for a successful read query, or false on failure
*/
- private function doProfiledQuery( $sql, $commentedSql, $isWrite, $fname ) {
+ private function attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname ) {
+ $this->beginIfImplied( $sql, $fname );
+
+ # Keep track of whether the transaction has write queries pending
+ if ( $isEffectiveWrite ) {
+ $this->lastWriteTime = microtime( true );
+ if ( $this->trxLevel && !$this->trxDoneWrites ) {
+ $this->trxDoneWrites = true;
+ $this->trxProfiler->transactionWritingIn(
+ $this->server, $this->getDomainID(), $this->trxShortId );
+ }
+ }
+
+ if ( $this->getFlag( self::DBO_DEBUG ) ) {
+ $this->queryLogger->debug( "{$this->getDomainID()} {$commentedSql}" );
+ }
+
$isMaster = !is_null( $this->getLBInfo( 'master' ) );
# generalizeSQL() will probably cut down the query to reasonable
# logging size most of the time. The substr is really just a sanity check.
$queryProf .= $this->trxShortId ? " [TRX#{$this->trxShortId}]" : "";
$startTime = microtime( true );
- if ( $this->profiler ) {
- $this->profiler->profileIn( $queryProf );
- }
+ $ps = $this->profiler ? ( $this->profiler )( $queryProf ) : null;
$this->affectedRowCount = null;
$ret = $this->doQuery( $commentedSql );
$this->affectedRowCount = $this->affectedRows();
- if ( $this->profiler ) {
- $this->profiler->profileOut( $queryProf );
- }
+ unset( $ps ); // profile out (if set)
$queryRuntime = max( microtime( true ) - $startTime, 0.0 );
- unset( $queryProfSection ); // profile out (if set)
-
if ( $ret !== false ) {
$this->lastPing = $startTime;
- if ( $isWrite && $this->trxLevel ) {
+ if ( $isEffectiveWrite && $this->trxLevel ) {
$this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
$this->trxWriteCallers[] = $fname;
}
$this->trxProfiler->recordQueryCompletion(
$queryProf,
$startTime,
- $isWrite,
- $isWrite ? $this->affectedRows() : $this->numRows( $ret )
+ $isEffectiveWrite,
+ $isEffectiveWrite ? $this->affectedRows() : $this->numRows( $ret )
);
$this->queryLogger->debug( $sql, [
'method' => $fname,
return $ret;
}
+ /**
+ * Start an implicit transaction if DBO_TRX is enabled and no transaction is active
+ *
+ * @param string $sql
+ * @param string $fname
+ */
+ private function beginIfImplied( $sql, $fname ) {
+ if (
+ !$this->trxLevel &&
+ $this->getFlag( self::DBO_TRX ) &&
+ $this->isTransactableQuery( $sql )
+ ) {
+ $this->begin( __METHOD__ . " ($fname)", self::TRANSACTION_INTERNAL );
+ $this->trxAutomatic = true;
+ }
+ }
+
/**
* Update the estimated run-time of a query, not counting large row lock times
*
}
/**
+ * Error out if the DB is not in a valid state for a query via query()
+ *
* @param string $sql
* @param string $fname
* @throws DBTransactionStateError
*/
private function assertTransactionStatus( $sql, $fname ) {
- if ( $this->getQueryVerb( $sql ) === 'ROLLBACK' ) { // transaction/savepoint
+ $verb = $this->getQueryVerb( $sql );
+ if ( $verb === 'USE' ) {
+ throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead." );
+ }
+
+ if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
return;
}
}
/**
- * Determine whether or not it is safe to retry queries after a database
- * connection is lost
+ * Determine whether it is safe to retry queries after a database connection is lost
*
* @param string $sql SQL query
* @param bool $priorWritesPending Whether there is a transaction open with
}
/**
- * Clean things up after session (and thus transaction) loss
+ * Clean things up after session (and thus transaction) loss before reconnect
*/
- private function handleSessionLoss() {
+ private function handleSessionLossPreconnect() {
// Clean up tracking of session-level things...
// https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
// https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
// https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
$this->namedLocksHeld = [];
// Session loss implies transaction loss
- $this->handleTransactionLoss();
- }
-
- /**
- * Clean things up after transaction loss
- */
- private function handleTransactionLoss() {
$this->trxLevel = 0;
$this->trxAtomicCounter = 0;
$this->trxIdleCallbacks = []; // T67263; transaction already lost
$this->trxPreCommitCallbacks = []; // T67263; transaction already lost
+ // @note: leave trxRecurringCallbacks in place
+ if ( $this->trxDoneWrites ) {
+ $this->trxProfiler->transactionWritingOut(
+ $this->server,
+ $this->getDomainID(),
+ $this->trxShortId,
+ $this->pendingWriteQueryDuration( self::ESTIMATE_TOTAL ),
+ $this->trxWriteAffectedRows
+ );
+ }
+ }
+
+ /**
+ * Clean things up after session (and thus transaction) loss after reconnect
+ */
+ private function handleSessionLossPostconnect() {
try {
// Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
// If callback suppression is set then the array will remain unhandled.
if ( $tempIgnore ) {
$this->queryLogger->debug( "SQL ERROR (ignored): $error\n" );
} else {
- $exception = $this->makeQueryException( $error, $errno, $sql, $fname );
+ $exception = $this->getQueryExceptionAndLog( $error, $errno, $sql, $fname );
throw $exception;
}
* @param string $fname
* @return DBError
*/
- private function makeQueryException( $error, $errno, $sql, $fname ) {
+ private function getQueryExceptionAndLog( $error, $errno, $sql, $fname ) {
$sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
$this->queryLogger->error(
"{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
'error' => $error,
'sql1line' => $sql1line,
'fname' => $fname,
+ 'trace' => ( new RuntimeException() )->getTraceAsString()
] )
);
$this->queryLogger->debug( "SQL ERROR: " . $error . "\n" );
}
}
- /**
- * Quotes an identifier using `backticks` or "double quotes" depending on the database type.
- * MySQL uses `backticks` while basically everything else uses double quotes.
- * Since MySQL is the odd one out here the double quotes are our generic
- * and we implement backticks in DatabaseMysqlBase.
- *
- * @param string $s
- * @return string
- */
public function addIdentifierQuotes( $s ) {
return '"' . str_replace( '"', '""', $s ) . '"';
}
return;
}
+ $uniqueIndexes = (array)$uniqueIndexes;
// Single row case
if ( !is_array( reset( $rows ) ) ) {
$rows = [ $rows ];
$this->query( $sql, $fname );
}
- public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
+ public function upsert( $table, array $rows, $uniqueIndexes, array $set,
$fname = __METHOD__
) {
if ( $rows === [] ) {
return true; // nothing to do
}
+ $uniqueIndexes = (array)$uniqueIndexes;
if ( !is_array( reset( $rows ) ) ) {
$rows = [ $rows ];
}
}
/**
- * @return bool Whether it is safe to assume the given error only caused statement rollback
+ * @return bool Whether it is known that the last query error only caused statement rollback
* @note This is for backwards compatibility for callers catching DBError exceptions in
* order to ignore problems like duplicate key errors or foriegn key violations
* @since 1.31
throw new DBUnexpectedError( $this, $msg );
}
- // Avoid fatals if close() was called
- $this->assertOpen();
+ $this->assertHasConnectionHandle();
$this->doBegin( $fname );
$this->trxStatus = self::STATUS_TRX_OK;
}
}
- // Avoid fatals if close() was called
- $this->assertOpen();
+ $this->assertHasConnectionHandle();
$this->runOnTransactionPreCommitCallbacks();
}
if ( $trxActive ) {
- // Avoid fatals if close() was called
- $this->assertOpen();
+ $this->assertHasConnectionHandle();
$this->doRollback( $fname );
$this->trxStatus = self::STATUS_TRX_NONE;
$this->closeConnection();
$this->opened = false;
$this->conn = false;
+
+ $this->handleSessionLossPreconnect();
+
try {
$this->open(
$this->server,
);
}
- $this->handleSessionLoss();
+ $this->handleSessionLossPostconnect();
return $ok;
}
$this->opened = false;
$this->conn = false;
$this->trxEndCallbacks = []; // don't copy
- $this->handleSessionLoss(); // no trx or locks anymore
+ $this->handleSessionLossPreconnect(); // no trx or locks anymore
$this->open(
$this->server,
$this->user,