GoogleMessage::getPayload

public function getPayload(): string
{
	$data = [
		"data" => [
			'contentTitle' => $this->title,
			"contentText" => $this->text,
			"badge" => $this->badge,
			"messageParams" => $this->customProperties,
			"category" => $this->getCategory(),
			"sound" => $this->getSound(),
		],
		"time_to_live" => $this->expiryValue,
		"priority" => "high",
		"registration_ids" => $this->deviceTokens
	];

	return $this->strippedPayload($data);
}