pocketmine\utils\BinaryStream::getBuffer PHP Method

    public function getBuffer()
    {
        return $this->buffer;
    }

 public function requestChunkTask($x, $z)
 {
     $chunk = $this->getChunk($x, $z, false);
     if (!$chunk instanceof Chunk) {
         throw new ChunkException("Invalid Chunk sent");
     }
     $tiles = "";
     if (count($chunk->getTiles()) > 0) {
         $nbt = new NBT(NBT::LITTLE_ENDIAN);
         $list = [];
         foreach ($chunk->getTiles() as $tile) {
             if ($tile instanceof Spawnable) {
                 $list[] = $tile->getSpawnCompound();
             }
         }
         $nbt->setData($list);
         $tiles = $nbt->write(true);
     }
     $extraData = new BinaryStream();
     $extraData->putLInt(count($chunk->getBlockExtraDataArray()));
     foreach ($chunk->getBlockExtraDataArray() as $key => $value) {
         $extraData->putLInt($key);
         $extraData->putLShort($value);
     }
     $ordered = $chunk->getBlockIdArray() . $chunk->getBlockDataArray() . $chunk->getBlockSkyLightArray() . $chunk->getBlockLightArray() . pack("C*", ...$chunk->getHeightMapArray()) . pack("N*", ...$chunk->getBiomeColorArray()) . $extraData->getBuffer() . $tiles;
     $this->getLevel()->chunkRequestCallback($x, $z, $ordered, FullChunkDataPacket::ORDER_LAYERED);
     return null;
 }