Since Alice's refund scenario starts with generating the temporary wallet
from keys to claim the XMR which results in Alice' unloading the wallet.
Alice then loads her original wallet to be able to handle more swaps.
Since Alice is in the role of the long running daemon handling concurrent
swaps, the operation to close, claim and re-open her default wallet must
be atomic.
This PR adds an additional step, that sweeps all the refunded XMR back into
the default wallet. In order to ensure that this is possible, Alice has to
ensure that the locked XMR got enough confirmations.
These changes allow us to assert Alice's balance after refunding.
The execution params don't change throughout the lifetime of the
program. They can be set in the wallet at the very beginning.
This simplifies the interface of the wallet functions.
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>
Instead of spawning the swap inside the event loop we send the swap back
to the caller to be spawned. This means we no longer need the remote handle
that was only used in the tests.
This now properly logs the swap results in production.
It also gives us more control over Alice's swap in the tests.
Instead, we use a regular loop and extract everything into a function
that can be independently tested.
`backoff` would be useful to retry the actual call to the node.
The bitcoin::Wallet::sync_wallet function doesn't do anything else
other than delegating. As such, we have just as much information
about what went wrong inside this function as we have outside.
By moving the .context call into the function, we can avoid repeating
us on every call-site.
Instead of leaking the tokio::sync:⌚:Receiver type in our
return value, we create a newtype that implements the desired
interface. This allows us to get rid of the `RateService` structs
and instead implement `LatestRate` directly on top of this struct.
Given that `LatestRate` is only used within the event_loop module,
we move the definition of this type into there.
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.
261: Sweep xmr funds from generated temp wallet r=da-kami a=da-kami
Fixes#252
Please review by commit :)
Did a few cleanups before actually doing the feature.
Please note the comment that influenced this solution: https://github.com/comit-network/xmr-btc-swap/issues/252#issuecomment-789387074
Co-authored-by: Daniel Karzel <daniel@comit.network>
Container initialization and wallet initialization have to ensure to use the same wallet name.
In order to avoid problems constants are introduced to ensure we use the same wallet name.
Prefixing docker-containers and -networks is a necessity to be able to spin up multiple containers and networks.
However, there is no reason to prefix the wallet names that live inside a container. One cannot add a wallet with
the same name twice, so the prefixing of wallets does not bring any advantage. When re-opening a wallet by name
the wallet name prefix is cumbersome and was thus removed.
Instead of instantiating the `EventLoop` within the builder, we only
pass in the necessary arguments (which is the `EventLoopHandle`) to
the Builder upon `new`.
This is work towards #255 which will require us to perform network
communication (which implies having the `EventLoop`) before starting
a swap.
If our expression directly evaluates to a future, we don't need to
create an async block.
This requires us to have `EventLoopRun::run` consume the instance
instead of just taking a mutable reference (otherwise we run into
lifetime issues). However, that is better anyway because `run` is
an endless loop so you never get to use the handle afterwards
anyway.
If communication with the other party fails the program should stop and the user should see the respective error.
Communication errors are handled in the event-loop. Upon a communication error the event loop is stopped.
Since the event loop is only stopped upon error the Result returned from the event loop is Infallible.
If one of the two futures, event loop and swap, finishes (success/failure) the other future should be stopped as well.
We use tokio::selec! to stop either future if the other stops.
In order to ensure that we can atomically generate_from_keys and then reload a wallet,
we have to wrap the client of the monero wallet RPC inside a mutex.
When introducing the Mutex I noticed that several inner RPC calls were leaking to the
swap crate monero wallet. As this is a violation of boundaries I introduced the traits
`GetAddress`, `WalletBlockHeight` and `Refresh`.
Note that the monero wallet could potentially know its own public view key and
public spend key. If we refactor the wallet to include this information upon wallet
creation we can also generate addresses using `monero::Address::standard`.
The bitcoind wallet required the user to run a bitcoind node. It was replaced with a bdk wallet which allows the user to connect to an electrum instance hosted remotely. An electrum and bitcoind testcontainer were created to the test the bdk wallet. The electrum container reads the blockdata from the bitcoind testcontainer through a shared volume. bitcoind-harness was removed as bitcoind initialisation code was moved into test_utils. The bdk wallet differs from the bitcoind wallet in that it needs to be manually synced with an electrum node. We synchronise the wallet once upon initialisation to prevent a potentially long running blocking task from interrupting protocol execution. The electrum HTTP API was used to get the latest block height and the transaction block height as this functionality was not present in the bdk wallet API or it required the bdk wallet to be re-synced to get an up to date value.
