Reworked Alice XmrLocked state transition handler to handle the
scenario when Alice received the encsig but Bob refunds.
Previously Alice was trying to redeem after receiving the encsig
without checking if t1 had elapsed.
Use reusable test init functions for happy path test
Extract tracing setup to reusable function
Move test initialization to seperate functions
Increase stack size in CI
Fix monero max finality time
Force Bob swarm polling to send message 2
Run Bob state to xmr_locked in punish test to force the sending of
message2. Previously Bob state was run until btc_locked. Although
this was the right thing to do, message2 was not being sent as the
swarm was not polled in btc_locked. Alice punish test passes.
Add info logging to executor
Consolidate and simplify swap execution. Generators are no longer
needed. Consolidate recovery and swap data structures. The
recursive calls can be replaced with a loop if returning prior to
completion is desired for testing purposes.
Fill out alice abort path
Move state machine executors into seperate files
Not compiling due to recursion/async issues
Fix async recursion compilation errors
Fix Bob swap execution
Remove check for ack message from Alice. Seems like a bad idea to
rely on an acknowledgement message instead of looking at the
blockchain.
Fix Bob abort
Fix warnings
Xmr lock complete
Add TxCancel submit to XmrLocked
Bob swap completed
Remove alice
This introduces a lot of duplication between the binary and the
library, but it's okay because this module should only be a temporary
measure until we allow recovery to be handled by the original state
machine.
Also, fix a bug in `xmr_btc::alice::action_generator` caused by the
incorrect assumption that Alice's ability to punish Bob could be
determined before the cancel transaction hits the blockchain.
Making build times considerably faster.
On my machine, after running `cargo clean`, `cargo build -p swap`
takes 2min 19s.
The updated dependency also comes with a critical fix to the `Scalar`
type, which originally wrongly assumed that secp256k1 and ed25519
scalars had the same endianness. For this reason, we now have to
reverse the bytes of recovered scalars if we are to use them on a
different chain.
Finally, there is no need to append `RUST_MIN_STACK=100000000` to
avoid stack overflows in tests and when running the binary.
Before this patch Bob is not sending message 3. This is because we are not
polling Bob's swarm correctly. To fix it we can just mimic the other NB's and
bubble up an event when Bob receives message 3 response from Alice, this way we
can `await` upon this event which triggers polling, making Bob's swarm send the
message.
Also:
- Move generator functions to `alice` and `bob` modules. This makes
using `tracing` a lot easier, since the context of the file name let's
us differentiate between Alice's and Bob's generator logs more
clearly.
- Accept 0 confirmations when watching for the Monero lock
transaction. This should eventually be configured by the application,
but in the tests it's making things unexpectedly slower.
The database is now bound to a type eg. alice::State or bob::State.
The caller cannot expect to retrieve a type that is different to
the type that was stored.
NOTE: This implementation saves secrets to disk! It is not
secure.
The storage API allows the caller to atomically record the state
of the protocol. The user can retrieve this recorded state and
re-commence the protocol from that point. The state is recorded
using a hard coded key, causing it to overwrite the previously
recorded state. This limitation means that this recovery
mechanism should not be used in a program that simultaneously
manages the execution of multiple swaps.
An e2e test was added to show how to save, recover and resume
protocol execution. This logic could also be integrated into the
run_until functions to automate saving but was not included at
this stage as protocol execution is currently under development.
Serialisation and deserialisation was implemented on the states
to allow the to be stored using the database. Currently the
secret's are also being stored to disk but should be recovered
from a seed or wallets.
Instead of checking once to see if Monero's `TxLock` has been
published, the new trait should keep looking until the transaction has
been found.
The new trait also allows the caller to set an expected number of
confirmations on the transaction.
The implementation of the trait is currently part of test code, but it
should be similar to what we will eventually do for an application.
Mimics what @thomaseizinger did here [1] and here [2].
This has the advantage that the consumer has more freedom to execute
`Action`s without having to implement particular traits. The error
handling required inside this protocol-executing function is also
reduced.
As discussed with Thomas, for this approach to work well, the
trait functions such as `receive_transfer_proof` should be infallible,
and the implementer should be forced to hide IO errors behind a retry
mechanism.
All of these asynchronous calls need to be "raced" against
the abort condition (determined by the `refund_timelock`), which is
missing in the current state of the implementation.
The initial handshake of the protocol has not been included here,
because it may not be easy to integrate this approach with libp2p, but
a couple of messages still need to exchanged. I need @tcharding to
tell me if it's feasible/good to do it like this.
[1]
https://github.com/comit-network/comit-rs/blob/move-nectar-swap-to-comit/nectar/src/swap/comit/herc20_hbit.rs#L57-L184.
[2] e584d2b14f/nectar/src/swap.rs (L716-L751).
There are no guarantees that send_message and receive_massage do not block
the flow of execution. Therefore they must be paired between Alice/Bob, one
send to one receive in the correct order.
Define Alice to call `receive_message` first, with Bob sending the message. Do
this because we are expecting Alice to be have a well known address, there is no
currently such assumption for Bob.
Previously there was a delay making a get raw transaction call to
give some time for a transaction to be confirmed on the blockchain.
This has been replaced with a loop that waits until the call is
succesful.
Previously we were testing the protocol by manually driving Alice and
Bob's state machines. This logic has now be moved to an async state
transition function that can take any possible state as input. The
state transition function is called in a loop until it returns the
desired state. This allows use to interrupt midway through the protocol
and perform refund and punish tests. This design was chosen over a
generator based implementation because the the generator based
implementation results in a impure state transition function that is
difficult to reason about and prone to bugs.
Test related code was extracted into the tests folder.
The 2b and 4b states were renamed to be consistent with the rest.
Macros were used to reduce code duplication when converting
child states to their parent states and vice versa.
Todos were added were neccessary.
