valid-paypal-standard-ipn-request action-hookWC 1.0

Usage

add_action( 'valid-paypal-standard-ipn-request', 'wp_kama_valid_paypal_standard_ipn_request_action' );

/**
 * Function for `valid-paypal-standard-ipn-request` action-hook.
 * 
 * @param  $posted 
 *
 * @return void
 */
function wp_kama_valid_paypal_standard_ipn_request_action( $posted ){

	// action...
}
$posted
-

Where the hook is called

WC_Gateway_Paypal_IPN_Handler::check_response()
valid-paypal-standard-ipn-request
woocommerce/includes/gateways/paypal/includes/class-wc-gateway-paypal-ipn-handler.php 49
do_action( 'valid-paypal-standard-ipn-request', $posted );

Where the hook is used in WooCommerce

woocommerce/includes/gateways/paypal/includes/class-wc-gateway-paypal-ipn-handler.php 35
add_action( 'valid-paypal-standard-ipn-request', array( $this, 'valid_response' ) );