BLOCKCHAIN-BASED ELECTRONIC BILL CANCELLATION METHOD, APPARATUS, AND ELECTRONIC DEVICE

1 . A computer-implemented method for blockchain-based electronic bill cancellation, comprising:

in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted by a blockchain node;

in response to determining that the target electronic bill has been accounted:

creating a reversed bill corresponding to the target electronic bill; and

broadcasting the reversed bill corresponding to the target electronic bill to the blockchain for storage;

in response to detecting a second cancellation transaction broadcasted to the blockchain, the cancellation transaction corresponding to a second target electronic bill, determining whether the second target electronic bill has been accounted by the blockchain node; and

in response to determining that the second target electronic bill has not been accounted, updating the second target electronic bill to a cancelled state.

2 . The computer-implemented method according to claim 1 , wherein determining whether a target electronic bill has been accounted comprises:

determining whether the target electronic bill is in an accounted state;

if the target electronic bill is in the accounted state, determining that the target electronic bill has been accounted; or

if the target electronic bill is not in the accounted state, determining that the target electronic bill has not been accounted.

3 . The computer-implemented method according to claim 1 , wherein broadcasting the reversed bill corresponding to the target electronic bill to the blockchain for storage comprises:

invoking a bill creation logic specified in a smart contract deployed on the blockchain in creating the reversed bill corresponding to the target electronic bill.

4 . The computer-implemented method according to claim 1 , wherein:

the cancellation transaction corresponding to the target electronic bill comprises a refund transaction corresponding to the target electronic bill and the cancellation transaction broadcasted to the blockchain comprises the cancellation transaction broadcasted by a drawee of the target electronic bill to the blockchain; and

further comprising instructing a drawer of the target electronic bill to perform refund processing on the target electronic bill after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage.

5 . The computer-implemented method according to claim 4 , wherein the drawer of the target electronic bill subscribes to a bill state of the target electronic bill maintained by the blockchain node; and

wherein instructing a drawer of the target electronic bill to perform refund processing on the target electronic bill after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage comprises:

after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage, updating the target electronic bill to a reversed bill-created state, and pushing the reversed bill-created state of the target electronic bill to the drawer to trigger the drawer to perform refund processing on the target electronic bill.

6 . The computer-implemented method according to claim 4 , wherein in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted comprises:

in response to the refund transaction, invoking a refund verification logic specified in a smart contract deployed on the blockchain to determine whether the target electronic bill satisfies refund criteria; and

in response to a monitored verification success event generated by the smart contract and corresponding to the target electronic bill, determining whether the target electronic bill has been accounted.

7 . The computer-implemented method according to claim 6 , wherein the refund criteria comprise refund permission criteria, refund amount criteria, and refund period criteria.

8 . The computer-implemented method according to claim 1 , wherein the cancellation transaction broadcasted to the blockchain comprises a cancellation transaction broadcasted by a drawer of the target electronic bill to the blockchain; and

in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted comprises:

in response to the cancellation transaction, invoking a cancellation verification logic specified in a smart contract deployed on the blockchain to determine whether the target electronic bill satisfies cancellation criteria; and

in response to a monitored verification success event generated by the smart contract and corresponding to the target electronic bill, determining whether the target electronic bill has been accounted.

9 . The computer-implemented method according to claim 8 , wherein the cancellation criteria comprise cancellation permission criteria and cancellation period criteria.

10 . A computer-implemented system for blockchain-based electronic bill cancellation, comprising:

one or more computers; and

one or more computer memory devices interoperably coupled with the one or more computers and having tangible, non-transitory, machine-readable media storing one or more instructions that, when executed by the one or more computers, perform one or more operations comprising:

in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted by a blockchain node;

in response to determining that the target electronic bill has been accounted:

creating a reversed bill corresponding to the target electronic bill; and

broadcasting the reversed bill corresponding to the target electronic bill to the blockchain for storage;

in response to detecting a second cancellation transaction broadcasted to the blockchain, the cancellation transaction corresponding to a second target electronic bill, determining whether the second target electronic bill has been accounted by the blockchain node; and

in response to determining that the second target electronic bill has not been accounted, updating the second target electronic bill to a cancelled state.

11 . The computer-implemented system according to claim 10 , wherein determining whether a target electronic bill has been accounted comprises:

determining whether the target electronic bill is in an accounted state;

if the target electronic bill is in the accounted state, determining that the target electronic bill has been accounted; or

if the target electronic bill is not in the accounted state, determining that the target electronic bill has not been accounted.

12 . The computer-implemented system according to claim 10 , wherein broadcasting the reversed bill corresponding to the target electronic bill to the blockchain for storage comprises invoking a bill creation logic specified in a smart contract deployed on the blockchain in creating the reversed bill corresponding to the target electronic bill.

13 . The computer-implemented system according to claim 10 , wherein:

the cancellation transaction corresponding to the target electronic bill comprises a refund transaction corresponding to the target electronic bill and the cancellation transaction broadcasted to the blockchain comprises the cancellation transaction broadcasted by a drawee of the target electronic bill to the blockchain; and

the operations further comprise instructing a drawer of the target electronic bill to perform refund processing on the target electronic bill after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage.

14 . The computer-implemented system according to claim 13 , wherein the drawer of the target electronic bill subscribes to a bill state of the target electronic bill maintained by the blockchain node; and

wherein instructing a drawer of the target electronic bill to perform refund processing on the target electronic bill after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage comprises:

after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage, updating the target electronic bill to a reversed bill-created state, and pushing the reversed bill-created state of the target electronic bill to the drawer to trigger the drawer to perform refund processing on the target electronic bill.

15 . The computer-implemented system according to claim 13 , wherein in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted comprises:

in response to the refund transaction, invoking a refund verification logic specified in a smart contract deployed on the blockchain to determine whether the target electronic bill satisfies refund criteria; and

in response to a monitored verification success event generated by the smart contract and corresponding to the target electronic bill, determining whether the target electronic bill has been accounted.

16 . The computer-implemented system according to claim 10 , wherein the cancellation transaction broadcasted to the blockchain comprises a cancellation transaction broadcasted by a drawer of the target electronic bill to the blockchain; and

in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted comprises:

in response to the cancellation transaction, invoking a cancellation verification logic specified in a smart contract deployed on the blockchain to determine whether the target electronic bill satisfies cancellation criteria; and

in response to a monitored verification success event generated by the smart contract and corresponding to the target electronic bill, determining whether the target electronic bill has been accounted.

17 . A non-transitory, computer-readable medium storing one or more instructions executable by a computer system to perform operations for blockchain-based electronic bill cancellation, comprising:

in response to detecting a cancellation transaction broadcasted to a blockchain that stores electronic bills, the cancellation transaction corresponding to a target electronic bill, determining whether the target electronic bill has been accounted by a blockchain node;

in response to determining that the target electronic bill has been accounted:

creating a reversed bill corresponding to the target electronic bill; and

broadcasting the reversed bill corresponding to the target electronic bill to the blockchain for storage;

in response to detecting a second cancellation transaction broadcasted to the blockchain, the cancellation transaction corresponding to a second target electronic bill, determining whether the second target electronic bill has been accounted by the blockchain node; and

in response to determining that the second target electronic bill has not been accounted, updating the second target electronic bill to a cancelled state.

18 . The non-transitory, computer-readable medium according to claim 17 , wherein determining whether a target electronic bill has been accounted comprises:

determining whether the target electronic bill is in an accounted state;

if the target electronic bill is in the accounted state, determining that the target electronic bill has been accounted; or

if the target electronic bill is not in the accounted state, determining that the target electronic bill has not been accounted.

19 . The non-transitory, computer-readable medium according to claim 17 , wherein broadcasting the reversed bill corresponding to the target electronic bill to the blockchain for storage comprises invoking a bill creation logic specified in a smart contract deployed on the blockchain in creating the reversed bill corresponding to the target electronic bill.

20 . The non-transitory, computer-readable medium according to claim 17 , wherein:

the cancellation transaction corresponding to the target electronic bill comprises a refund transaction corresponding to the target electronic bill and the cancellation transaction broadcasted to the blockchain comprises the cancellation transaction broadcasted by a drawee of the target electronic bill to the blockchain; and

the operations further comprise instructing a drawer of the target electronic bill to perform refund processing on the target electronic bill after the reversed bill corresponding to the target electronic bill is broadcasted to the blockchain for storage.