Previously, we were forwarding incoming messages from peers to all
swaps that were currently running. That is obviously wrong. The new
design scopes an `EventLoopHandle` to a specific PeerId to avoid
this problem.
We have a repeated pattern where we construct one of our
Tx{Cancel,Redeem,Punish,Refund,Lock} transactions and wait until
the status of this transaction changes. We can make this more
ergonomic by creating and implementing a `Watchable` trait that
gives access to the TxId and relevant script for this transaction.
This allows us to remove a parameter from the `watch_until_status`
function.
Additionally, there is a 2nd pattern: "Completing" one of these
transaction and waiting until they are confirmed with the configured
number of blocks for finality. We can make this more ergonomic by
returning a future from `broadcast` that callers can await in case
they want to wait for the broadcasted transaction to reach finality.
We achieve our optimizations in three ways:
1. Batching calls instead of making them individually.
To get access to the batch calls, we replace all our
calls to the HTTP interface with RPC calls.
2. Never directly make network calls based on function
calls on the wallet.
Instead, inquiring about the status of a script always
just returns information based on local data. With every
call, we check when we last refreshed the local data and
do so if the data is considered to be too old. This
interval is configurable.
3. Use electrum's notification feature to get updated
with the latest blockheight.
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>
Co-authored-by: Rishab Sharma <rishflab@hotmail.com>
We reduce indirection by constructing TxPunish directly based off
`State3` and make the type itself more powerful by moving the logic
of completing it with a signature onto it.
This allows us to have access to RedeemTx from within the scope
of the state transition which we are going to need for more
efficient watching of what happens to this TX on the blockchain.
This reduces the overall amount of LoC that imports take up in our
codebase by almost 100.
It also makes merge-conflicts less likely because there is less
grouping together of imports that may lead to layout changes which
in turn can cause merge conflicts.
We eliminate unnecessary layers of indirection for broadcasting logic
and force our callers to provide us with the `kind` of transaction
that we are publishing.
Eventually, we can replace this string with some type-system magic
we can derive the name from the actual transaction. For now, we just
require the caller to duplicate this information because it is faster
and good enough TM.
This struct is a wallet. The only thing it can meaningfully broadcast
are transactions. The fact that they have to be signed for that is
implied. You cannot broadcast unsigned transactions.
Abstracting over the individual bits of functionality of the wallet
does have its place, especially if one wants to keep a separation
of an abstract protocol library that other people can use with their
own wallets.
However, at the moment, the traits only cause unnecessary friction.
We can always add such abstraction layers again once we need them.
The only reason we need this argument is because we need to access
the output descriptor. We can save that one ahead of time at when
we construct the type.
To achieve this we also:
- upgrade rust-bitcoin to 0.26
- upgrade bitcoin-harness to latest version (which also depends bitcoin 0.26)
- upgrade to latest edcsa-fun
- replace cross_curve_dleq proof with sigma_fun (to avoid an upgrade dance over there)
We are aware of issues of timeouts when waiting for acknowledgements.
Also, to properly supports acks in a multiple swap context, we need to
revert to doing event processing on the behaviour so that we can link
leverage the `RequestResponse` libp2p behaviour and link the messages
requests ids to swap ids when receiving an ack or response.
Acks are usefully for specific scenarios where we queue a message on the
behaviour to be sent, save as sent in the DB but crash before the
message is actually sent. With acks we are able to resume the swap,
without ack, the swap will abort (refund).
`alice::swap::run_until` will be called once the execution setup is
done. The steps before are directly handled by the event loop,
hence no channels are needed for said steps: connection established,
swap request/response & execution setup.
If dialing Bob fails Alice waits for the acknowledgement of the transfer proof indefinitely.
The timout prevents her execution from hanging.
Added a ToDo to re-visit the ack receivers. They don't add value at the moment and should be removed.
As per the proposed changed in the sequence diagram.
The aim is to have a unique terminology per message instead of having
the same name for 2 consequent messages that share the same behaviour.
Note that the aim is to remove the shared `RequestResponse` behaviours.
149: Fix Alice redeem scenario r=da-kami a=da-kami
Follow up of #144, partial fix of https://github.com/comit-network/xmr-btc-swap/issues/137
Fix Alice redeem scenario
- Properly check the timelocks before trying to redeem
- Distinguish different failure scenarios and reactions to it.
- if we fail to construct the redeem transaction: wait for cancel.
- if we fail to publish the redeem transaction: wait for cancel but let the user know that restarting the application will result in retrying to publish the tx.
- if we succeed to publish the tx but then fail when waiting for finality, print error to the user (secreat already leaked, the user has to check manually if the tx was included)
Co-authored-by: Daniel Karzel <daniel@comit.network>
- Properly check the timelocks before trying to redeem
- Distinguish different failure scenarios and reactions to it.
- if we fail to construct the redeem transaction: wait for cancel.
- if we fail to publish the redeem transaction: wait for cancel but let the user know that restarting the application will result in retrying to publish the tx.
- if we succeed to publish the tx but then fail when waiting for finality, print error to the user (secreat already leaked, the user has to check manually if the tx was included)
If we wait for lock transaction confirmations immediately after sending the transaction without saving this state to the DB this might cause locking the money twice.
An additional state is needed for such a scenario.
We already select waiting for this message with the cancellation expiry,
we do not need add another guard that tries to guess how long it would
for the Monero transaction to be finalised.
Created network, storage and protocol modules. Organised
files into the modules where the belong.
xmr_btc crate moved into isolated modulein swap crate.
Remove the xmr_btc module and integrate into swap crate.
Consolidate message related code
Reorganise imports
Remove unused parent Message enum
Remove unused parent State enum
Remove unused dependencies from Cargo.toml