- Swap-id is exchanged during execution setup. CLI (Bob) sends the swap-id to be used in his first message.
- Transfer poof and encryption signature messages include the swap-id so it can be properly associated with the correct swap.
- ASB: Encryption signatures are associated with swaps by swap-id, not peer-id.
- ASB: Transfer proofs are still associated to peer-ids (because they have to be sent to the respective peer), but the ASB can buffer multiple
- CLI: Incoming transfer proofs are checked for matching swap-id. If a transfer proof with a different swap-id than the current executing swap is received it will be ignored. We can change this to saving into the database.
Includes concurrent swap tests with the same Bob.
- One test that pauses and starts an additional swap after the transfer proof was received. Results in both swaps being redeemed after resuming the first swap.
- One test that pauses and starts an additional swap before the transfer proof is sent (just after BTC locked). Results in the second swap redeeming and the first swap being refunded (because the transfer proof on Bob's side is lost). Once we store transfer proofs that we receive during executing a different swap into the database both swaps should redeem.
Note that the monero harness was adapted to allow creating wallets with multiple outputs, which is needed for Alice.
Sending the transfer transaction in a distinct state helps ensuring
that we do not send the Monero lock transaction twice in a restart
scenario.
Waiting for the first transaction confirmation in a separate state
helps ensuring that we send the transfer proof in a restart scenario.
Once we resume unfinished swaps upon startup we have to ensure that
it is safe for Alice to act.
If Bob has locked BTC it is only make sense for Alice to lock up the
XMR as long as no timelock has expired. Hence we abort if the BTC is
locked, but any timelock expired already.
Instead of watching for status changes directly on bitcoin::Wallet,
we return a Subscription object back to the caller. This subscription
object can be re-used multiple times.
Among other things, this now allows callers of `broadcast` to decide
on what to wait for given the returned Subscription object.
The new API is also more concise which allows us to remove some of
the functions on the actor states in favor of simple inline calls.
Co-authored-by: rishflab <rishflab@hotmail.com>
Sometimes, a single sync is not enough because we are still waiting
for the block to be mined.
We introduce an abstraction that loops on fetching the latest balance
with a certain timeout for asserting the balance.
By using `test_writer`, cargo can automatically scope the output
of the test to the relevant thread and will also only output it
if the test fails or is run with `--nocapture`.
This also formats `log` events more nicely. Instead of
```
Mar 29 09:46:16.775 INFO log: Found message after comparing 82 lines log.target="testcontainers::core::wait_for_message" log.module_path="testcontainers::core::wait_for_message" log.file="/home/thomas/.cargo/registry/src/github.com-1ecc6299db9ec823/testcontainers-0.12.0/src/core/wait_for_message.rs" log.line=35
```
We now have
```
Mar 29 09:57:15.860 INFO testcontainers::core::wait_for_message: Found message after comparing 81 lines
```
The request-response behaviour that is used for sending the transfer
proof actually has a functionality for buffering a message if we
are currently not connected. However, the request-response behaviour
also emits a dial attempt and **drops** all buffered messages if this
dial attempt fails. For us, the dial attempt will very likely always
fail because Bob is very likely behind NAT and we have to wait for
him to reconnect to us.
To mitigate this, we build our own buffer within the EventLoop and
send transfer proofs as soon as we are connected again.
Resolves#348.
The swap should not be concerned with connection handling. This is
the responsibility of the overall application.
All but the execution-setup NetworkBehaviour are `request-response`
behaviours. These have built-in functionality to automatically emit
a dial attempt in case we are not connected at the time we want to
send a message. We remove all of the manual dialling code from the
swap in favor of this behaviour.
Additionally, we make sure to establish a connection as soon as the
EventLoop gets started. In case we ever loose the connection to Alice,
we try to re-establish it.
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>
