Is the implementation of a crowdfunded house that manages the accounting among shareholders.
- Any user can invest on the house, and get proportional shares of it.
- Uppon divest, the contract calculates the profit, according to the holders shares balance.
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Client sends a deposit promise, with nonce 0:
msgHash = hash(sender.address, depositValue, 0); -
Server verifies msgHash OK and signs:
serverSignature = sign(msgHash); -
Client open channel with promised payment:
openChannel(msgHash, serverSignature);
The contract will then return a channelId for use in future communications.
Similar to the previous scenario, the client now uses the opened channelId.
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Client sends a deposit promise:
msgHash = hash(channelId, depositValue, 0); -
Server verifies msgHash OK and signs:
serverSignature = sign(msgHash); -
Client updates channel with promised payment:
updateChannel(msgHash, serverSignature);
Here the client may try to trick and provided with the server signature he might decide not to top-up the channel with the promised value, but instead use the serverSignature to initiate a channel dispute.
Note here that the nonce in the msgHash is 0, and the contract will enforce the disputed value to be exactly equal to the channel balace (on the blockchain) when deciding for a nonce = 0 message. The server will still have chance to challenge and provide its dispute evidence.
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Client notifies server it wishes to close the channel and sends:
msgHash = hash(channelId, channelBalance, currentNonce);clientSignature = sign(msgHash); -
Server verifies msgHash and client signatures and calls:
closeChannel(msgHash, clientSignature);
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Client decides to open a dispute and calls:
openDispute(channelId); -
Each party then has a time window to send valid proofs:
setDisputeEvidence(msgHash, otherPartySignature, channelBalance, nonce); -
After the dispute period, any address can settle the dispute and close the channel.
closeDispute(bytes32 _channelId);