The current messaging system doesn’t have a way to inform the source chain that a message failed to be executed on the destination chain. This lack of information availability disallows contracts on the source chain to handle the cases where the message they sent failed or got stuck in the destination chain.
Incorporate a special function in the L2ToL2CrossDomainMessenger contract to send back unsuccessful message hashes back to the source chain after a given period of time has elapsed as well as a special function that receive and store the sent-back message hashes.
This will provide smart contracts in the different source chains with the flexibility to handle the cases where a message they sent failed, as they can add functions to reconstruct a message, compare it with the stored sent-back hashes in the L2ToL2CrossDomainMessenger and add the logic to handle the failure accordingly.
New functions:
function revert(bytes32 _messageHash) external: Sends the message hash back to the L2ToL2CrossDomainMessenger in the source chain.
relayMessage flow and have the CrossL2Inbox call the new receiveMessageHash function instead. This is due to this function living in the L2ToL2CrossDomainMessenger contract and relayMessage not allowing the target contract to be itself.function receiveMessageHash(uint256 _messageSource, uint256 _messageDestination, address _sender, bytes32 _messageHash) external : Receives the message hashes of the unsuccessful messages hashes from the destination chains.
_sender and _origin is the L2ToL2CrossDomainMessenger and the caller the CrossL2Inbox.messageHash is returned to the source chain and no other chain, and that the destination of the original message is the chain where the message is coming from.<aside> 💡 This code should never be used in production. This code serves only to facilitate the communication of the idea.
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