*/ abstract public static function connect(ConnectionConfig $connectionConfig, CancellationToken $token = null): Promise; /** * @param Handle $handle */ public function __construct(Handle $handle) { $this->handle = $handle; $this->release = $this->callableFromInstanceMethod("release"); } /** * {@inheritdoc} */ final public function isAlive(): bool { return $this->handle->isAlive(); } /** * {@inheritdoc} * * @throws FailureException */ final public function lastUsedAt(): int { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->handle->lastUsedAt(); } /** * {@inheritdoc} */ final public function close() { if ($this->handle) { $this->handle->close(); } } /** * @param string $methodName Method to execute. * @param mixed ...$args Arguments to pass to function. * * @return Promise * * @throws FailureException */ private function send(string $methodName, ...$args): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } if ($this->busy) { return call(function () use ($methodName, $args) { while ($this->busy) { yield $this->busy->promise(); } return yield ([$this->handle, $methodName])(...$args); }); } return ([$this->handle, $methodName])(...$args); } /** * Releases the transaction lock. */ private function release() { \assert($this->busy !== null); $deferred = $this->busy; $this->busy = null; $deferred->resolve(); } /** * {@inheritdoc} */ final public function query(string $sql): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->send("query", $sql); } /** * {@inheritdoc} */ final public function execute(string $sql, array $params = []): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->send("execute", $sql, $params); } /** * {@inheritdoc} * * Statement instances returned by this method must also implement Operation. */ final public function prepare(string $sql): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->send("prepare", $sql); } /** * {@inheritdoc} */ final public function notify(string $channel, string $payload = ""): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->send("notify", $channel, $payload); } /** * {@inheritdoc} * * @throws FailureException */ final public function listen(string $channel): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->send("listen", $channel); } /** * {@inheritdoc} * * @throws FailureException */ final public function transaction(int $isolation = Transaction::ISOLATION_COMMITTED): Promise { if (! $this->handle) { throw new FailureException('Not connected'); } return call(function () use ($isolation) { switch ($isolation) { case Transaction::ISOLATION_UNCOMMITTED: yield $this->handle->query("BEGIN TRANSACTION ISOLATION LEVEL READ UNCOMMITTED"); break; case Transaction::ISOLATION_COMMITTED: yield $this->handle->query("BEGIN TRANSACTION ISOLATION LEVEL READ COMMITTED"); break; case Transaction::ISOLATION_REPEATABLE: yield $this->handle->query("BEGIN TRANSACTION ISOLATION LEVEL REPEATABLE READ"); break; case Transaction::ISOLATION_SERIALIZABLE: yield $this->handle->query("BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE"); break; default: throw new \Error("Invalid transaction type"); } $this->busy = new Deferred; return new ConnectionTransaction($this->handle, $isolation, $this->release); }); } /** * {@inheritdoc} * * @throws FailureException */ final public function quoteString(string $data): string { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->handle->quoteString($data); } /** * {@inheritdoc} * * @throws FailureException */ final public function quoteName(string $name): string { if (! $this->handle) { throw new FailureException('Not connected'); } return $this->handle->quoteName($name); } }