Implement additional callbacks as per ICS 26

[cwgoes]

Handle additional callbacks, ref https://github.com/cosmos/cosmos-sdk/pull/5401/files#diff-de4dba43d2cba47382cdb1c05d1f8c3cR3

[jackzampolin]

Ok, it appears that there are some substantial remaining issues to be resolved here that will block the demo. It does not appear that packet receipt is hooked up or working in the current code.

[cwgoes]

Ok, it appears that there are some substantial remaining issues to be resolved here that will block the demo. It does not appear that packet receipt is hooked up or working in the current code.

None of these points should be related to packet receipt. As far as I can tell from a quick read of the code, packet receipt is hooked up (see handler.go and handlePacketDataTransfer), and it's tested in keeper/relay_test.go (though the tests may not be complete, and it looks like handler_test.go should also include some tests for the full handler switch-case logic). Is that what you are referring to, or if not can you be more specific?

[mossid]

Packet receipts are only sent back when the token sending fails due to the invalid packet data or some receiving side logic, which we don't have in the current version of ICS20 spec/impl afaik

[cwgoes]

Packet receipts are only sent back when the token sending fails due to the invalid packet data or some receiving side logic, which we don't have in the current version of ICS20 spec/impl afaik

Can bankKeeper.AddCoins fail? If so, we'll need to handle this case.

[mossid]

Assuming the amount is correct, the only case that AddCoins fails is when the (oldCoins+amt) < 0, which I don't quite understand.

[fedekunze]

Packet receipts are only sent back when the token sending fails due to the invalid packet data or some receiving side logic

what is a packet receipt and where is this implemented?

[fedekunze]

Handle additional callbacks

can you point me to this item? which are the additional callbacks that need to be handled?

[jackzampolin]

Packet Receipt is the PacketAcknowledge afaik.

And the callbacks, according to the linked comment are:

// OnChanOpenInit, OnChanOpenTry, OnChanOpenAck, OnChanOpenConfirm, OnChanCLoseConfirm
// will be implemented according to ADR15 in the future PRs. Code left for reference.
//
// OnRecvPacket, OnAcknowledgementPacket, OnTimeoutPacket has been implemented according
// to ADR15.

[cwgoes]

Assuming the amount is correct, the only case that AddCoins fails is when the (oldCoins+amt) < 0, which I don't quite understand.

It seems to me like we should probably panic in this case, but I think it's worth building out the acknowledgement success/failure logic anyways, just to see how it works.