call->start_batch([OP_SEND_INITIAL_METADATA => $metadata]); } /** * Reads the next value from the server. * @return The next value from the server, or null if there is none */ public function read() { $batch = [OP_RECV_MESSAGE => true]; if ($this->metadata === null) { $batch[OP_RECV_INITIAL_METADATA] = true; } $read_event = $this->call->start_batch($batch); if ($this->metadata === null) { $this->metadata = $read_event->metadata; } return $this->deserializeResponse($read_event->message); } /** * Write a single message to the server. This cannot be called after * writesDone is called. * @param ByteBuffer $data The data to write */ public function write($data) { $this->call->start_batch([OP_SEND_MESSAGE => $data->serialize()]); } /** * Indicate that no more writes will be sent. */ public function writesDone() { $this->call->start_batch([OP_SEND_CLOSE_FROM_CLIENT => true]); } /** * Wait for the server to send the status, and return it. * @return object The status object, with integer $code, string $details, * and array $metadata members */ public function getStatus() { $status_event = $this->call->start_batch([ OP_RECV_STATUS_ON_CLIENT => true ]); return $status_event->status; } }