Some network and application specific code does not belong in the protocol module and was moved.
Eventloop, recovery and the outside behaviour were moved to the respective application module because they are application specific.
The `swap_setup` was moved into the network module because upon change both sides will have to be changed and should thus stay close together.
Having `spot_price` and `execution_setup` as separate protocols did not bring any advantages, but was problematic because we had to ensure that `execution_setup` would be triggered after `spot_price`. Because of this dependency it is better to combine the protocols into one.
Combining the protocols also allows a refactoring to get rid of the `libp2p-async-await` dependency.
Alice always listens for the `swap_setup` protocol. When Bob opens a substream on that protocol the spot price is communicated, and then all execution setup messages (swap-id and signature exchange).
Each test spawns swarm for Alice and Bob that only contains the spot_price behaviours and uses a memory transport.
Tests cover happy path (i.e. expected price is returned) and error scenarios.
Implementation of `TestRate` on `LatestRate` allows testing rate fetch error and quote calculation error behaviour.
Thanks to @thomaseizinger for ramping up the test framework for comit-rs in the past!
What goes over the wire should not be coupled to the errors being printed.
For the CLI and ASB we introduce a separate error enum that is used for logging.
When sending over the wire the errors are mapped to and from the `network::spot_price::Error`.
As part of Bob-specific spot_price code was moved from the network into bob.
Clearly separation of the network API from bob/alice.
Instead of forwarding every error, we deliberately ignore certain
variants that are not worth being printed to the log. In particular,
this concerns "UnsupportedProtocols" and "ResponseOmission".
To make this less verbose we introduce a macro for mapping a
`RequestResponseEvent` to `{alice,bob}::OutEvent`. We use a macro
because those `OutEvent`s are different types and the only other
way of abstracting over them would be to introduce traits that we
implement on both of them.
To make the macro easier to use, we move all the `From` implementations
that convert between the protocol and the more high-level behaviour
into the actual protocol module.
bmrng is a library providing a request-response channel that allows
the receiving end of the channel to send a response back to the sender.
This allows us to more accurately implement the functions on the
`EventLoopHandle`. In particular, we now _wait_ for the ACK of specific
messages from the other party before resolving the future.
For example, when sending the encrypted signature, the async function
on the `EventLoopHandle` does not resolve until we received the ACK
from the other party.
We also delete the `Channels` abstraction in favor of directly creating
bmrng channels. This allows us to directly control the channel buffer
which we set to 1 because we don't need more than that on Bob's side.
We don't need to hide the fields of this Behaviour as the only reason
for why this struct exists is because libp2p forces us to compose our
NetworkBehaviours into a new struct.
This allows us to remove all visibility modifiers from the message
fields because child modules (in this case {alice,bob}::state) can
always access private fields of structs.
It also moves the messages into a more natural place. Previously,
they were defined within the network layer even though they are
independent of the libp2p implementation.
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.
Decomposing a RequestResponseEvent is quite verbose. We can introduce
a helper function that does the matching for us and delegates to
specific `From` implementations for the protocol specific bits.
Previously, the user neither knew the price nor the maximum quantity
they could trade. We now request a quote from the user and display
it to them.
Fixes#255.
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.
265: Replace quote with spot-price protocol r=thomaseizinger a=thomaseizinger
This is essentially functionally equivalent but includes some
cleanups by removing a layer of abstraction: `spot_price::Behaviour`
is now just a type-alias for a request-response behaviour.
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>
This is essentially functionally equivalent but includes some
cleanups by removing a layer of abstraction: `spot_price::Behaviour`
is now just a type-alias for a request-response behaviour.
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.
Log messages are ideally as close to the functionality they are talking about, otherwise we might end up repeating ourselves on several callsites or the log messages gets outdated if the behaviour changes.
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.
Failure does not express what the error represents. It is only used for communication
errors for quote requests, receiving the XMR transfer proof and sending the encryption signature.
