public function searchItemByLocationIdAction() { $asset_id = $this->_request->getParam('asset_id', ''); if (!empty($asset_id)) { $coldchain = new Model_ColdChain(); $result = $coldchain->searchItemByLocationId($asset_id); } else { $result = array("error" => "Please provide coldchain asset id. e.g. (?asset_id=1)"); } echo Zend_Json::encode($result); }