queryCar.ts

async queryCar(stubHelper: StubHelper, args: string[]): Promise<any> {

        const verifiedArgs = await Helpers.checkArgs<{ key: string }>(args[0], Yup.object()
            .shape({
                key: Yup.string().required(),
            }));

        const car = stubHelper.getStateAsObject(verifiedArgs.key); //get the car from chaincode state

        if (!car) {
            throw new ChaincodeError('Car does not exist');
        }

        return car;
}