Previously, the `DummyConnectionHandler` offered a "keep alive" functionality,
i.e. it allowed users to set the value of what is returned from
`ConnectionHandler::keep_alive`. This handler is primarily used in tests or
`NetworkBehaviour`s that don't open any connections (like mDNS). In all of these
cases, it is statically known whether we want to keep connections alive. As
such, this functionality is better represented by a static
`KeepAliveConnectionHandler` that always returns `KeepAlive::Yes` and a
`DummyConnectionHandler` that always returns `KeepAlive::No`.
To follow the naming conventions described in
https://github.com/libp2p/rust-libp2p/issues/2217, we introduce a top-level
`keep_alive` and `dummy` behaviour in `libp2p-swarm` that contains both the
`NetworkBehaviour` and `ConnectionHandler` implementation for either case.
When generating an `OutEvent` `enum` definition for a user, derive `Debug`
for that `enum`.
Why not derive `Clone`, `PartialEq` and `Eq` for the generated `enum`
definition?
While it is fine to require all sub-`OutEvent`s to implement
`Debug`, the same does not apply to traits like `Clone`. I
suggest users that need `Clone` to define their own `OutEvent`.
A `ProtocolsHandler`, now `ConnectionHandler`, handels a connection, not
a protocol. Thus the name `CONNECTIONHandler` is more appropriate.
Next to the rename of `ProtocolsHandler` this commit renames the `mod
protocols_handler` to `mod handler`. Finally all combinators (e.g.
`ProtocolsHandlerSelect`) are renamed appropriately.
Implement `NetworkBehaviour` on `either::Either<L, R>` where both L
and R both implement `NetworkBehaviour`.
Add NetworkBehaviour derive tests for Either and Toggle
Co-authored-by: Max Inden <mail@max-inden.de>
Require `NetworkBehaviourAction::{DialPeer,DialAddress}` to contain a
`ProtocolsHandler`. This allows a behaviour to attach custom state to its
handler. The behaviour would no longer need to track this state separately
during connection establishment, thus reducing state required in a behaviour.
E.g. in the case of `libp2p-kad` the behaviour can include a `GetRecord` request
in its handler, or e.g. in the case of `libp2p-request-response` the behaviour
can include the first request in the handler.
Return `ProtocolsHandler` on connection error and close. This allows a behaviour
to extract its custom state previously included in the handler on connection
failure and connection closing. E.g. in the case of `libp2p-kad` the behaviour
could extract the attached `GetRecord` from the handler of the failed connection
and then start another connection attempt with a new handler with the same
`GetRecord` or bubble up an error to the user.
Co-authored-by: Thomas Eizinger <thomas@eizinger.io>
Change `Stream` implementation of `ExpandedSwarm` to return all
`SwarmEvents` instead of only the `NetworkBehaviour`'s events.
Remove `ExpandedSwarm::next_event`. Users can use `<ExpandedSwarm as
StreamExt>::next` instead.
Remove `ExpandedSwarm::next`. Users can use `<ExpandedSwarm as
StreamExt>::filter_map` instead.
