/**
* Decode a Message from raw network data
*
* @param string $data The data string to decode
* @return \LibDNS\Messages\Message
* @throws \UnexpectedValueException When the packet data is invalid
* @throws \InvalidArgumentException When a type subtype is unknown
*/
public function decode($data)
{
$packet = $this->packetFactory->create($data);
$decodingContext = $this->decodingContextFactory->create($packet);
$message = $this->messageFactory->create();
$this->decodeHeader($decodingContext, $message);
$questionRecords = $message->getQuestionRecords();
$expected = $decodingContext->getExpectedQuestionRecords();
for ($i = 0; $i < $expected; $i++) {
$questionRecords->add($this->decodeQuestionRecord($decodingContext));
}
$answerRecords = $message->getAnswerRecords();
$expected = $decodingContext->getExpectedAnswerRecords();
for ($i = 0; $i < $expected; $i++) {
$answerRecords->add($this->decodeResourceRecord($decodingContext));
}
$authorityRecords = $message->getAuthorityRecords();
$expected = $decodingContext->getExpectedAuthorityRecords();
for ($i = 0; $i < $expected; $i++) {
$authorityRecords->add($this->decodeResourceRecord($decodingContext));
}
$additionalRecords = $message->getAdditionalRecords();
$expected = $decodingContext->getExpectedAdditionalRecords();
for ($i = 0; $i < $expected; $i++) {
$additionalRecords->add($this->decodeResourceRecord($decodingContext));
}
if ($packet->getBytesRemaining() !== 0) {
throw new \UnexpectedValueException('Decode error: Unexpected data at end of packet');
}
return $message;
}
/**
* @param \LibDNS\Records\Question
*
* @return \LibDNS\Messages\Message
*/
protected function createRequest(Question $question) : Message
{
$request = $this->messageFactory->create(MessageTypes::QUERY);
$request->getQuestionRecords()->add($question);
$request->isRecursionDesired(true);
$request->setID($this->createId());
return $request;
}