We use the "precondition" feature of the `tokio::select!` macro to
avoid polling certain futures. In particular, we skip polling all
futures that - when resolved - require us to send a message to Alice.
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.
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.
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.
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.
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they are talking about, otherwise we might end up repeating ourselves on several callsites or the log messages gets outdated if the behaviour changes.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.
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).
Upgrade bitcoin harness dependency to latest commit
Upgrade backoff to fix failing tests. The previous version of backoff had a broken version of the retry function. Upgraded to a newer comit which fixes this problem.
Upgrade hyper to 0.14 as the 0.13 was bringing in tokio 0.2.24
Upgraded bitcoin harness to version that uses tokio 1.0 and reqwest 0.11
Upgrade reqwest to 0.11. Reqwest 0.11 uses tokio 1.0
Upgrade libp2p to 0.34 in preparation for tokio 1.0 upgrade
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.
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
