Check if product is new using observer

For detecting new entity you can use

$product = $observer->getEvent()->getProduct();
$product->isObjectNew();

Source: \Magento\NewRelicReporting\Model\Observer\ReportProductSaved

For me the isObjectNew() was available in catalog_product_save_before, but was not available in catalog_product_save_after. I simply created my own isNew variable in the Observer and set it to true in beforeSave and checked it in the afterSave methods.

<?php
class Some_Module_Model_Observer{
protected $isNew = false;
public function beforeSave($observer) {
    $product = $observer->getEvent()->getProduct();
    if($product->isObjectNew()){
        $this->isNew = true;
    }
}
public function afterSave($observer) {
    $product = $observer->getEvent()->getProduct();
    if($this->isNew){
        /*Add Logic Here*/
    }
}

}