public function getCcmLocationsAction() { $wh_id = $this->_request->getParam('wh_id'); if ($wh_id) { $coldchain = new Model_ColdChain(); $result = $coldchain->getCCMLocations($wh_id); } else { $result = array("error" => "Please provide wh_id param. e.g. (?wh_id=1)"); } echo Zend_Json::encode($result); }