Previously, a `ConnectionHandler` was immediately requested from the `NetworkBehaviour` as soon as a new dial was initiated or a new incoming connection accepted.
With this patch, we delay the creation of the handler until the connection is actually established and fully upgraded, i.e authenticated and multiplexed.
As a consequence, `NetworkBehaviour::new_handler` is now deprecated in favor of a new set of callbacks:
- `NetworkBehaviour::handle_pending_inbound_connection`
- `NetworkBehaviour::handle_pending_outbound_connection`
- `NetworkBehaviour::handle_established_inbound_connection`
- `NetworkBehaviour::handle_established_outbound_connection`
All callbacks are fallible, allowing the `NetworkBehaviour` to abort the connection either immediately or after it is fully established. All callbacks also receive a `ConnectionId` parameter which uniquely identifies the connection. For example, in case a `NetworkBehaviour` issues a dial via `NetworkBehaviourAction::Dial`, it can unambiguously detect this dial in these lifecycle callbacks via the `ConnectionId`.
Finally, `NetworkBehaviour::handle_pending_outbound_connection` also replaces `NetworkBehaviour::addresses_of_peer` by allowing the behaviour to return more addresses to be used for the dial.
Resolves#2824.
Pull-Request: #3254.
We create the `ConnectionId` for the new connection as part of `DialOpts`. This allows `NetworkBehaviour`s to accurately track state regarding their own dial attempts.
This patch is the main enabler of https://github.com/libp2p/rust-libp2p/pull/3254. Removing the `handler` field will allow us to deprecate the `NetworkBehaviour::new_handler` function in favor of four new ones that give more control over the connection lifecycle.
Most of this is trivial, apart from the rename of the `clippy::derive_hash_xor_eq` lint to `clippy::derived_hash_with_manual_eq`.
Instead of allowing that lint, we manually implement `PartialEq` and add a comment why the difference between the `PartialEq` and `Hash` implementations are okay.
In case an error happens for an outgoing connection, `Pool` reports an `OutgoingConnectionError`. This one is mapped to a `DialError` and reported via `SwarmEvent::OutgoingConnectionError` and `FromSwarm::DialFailure`.
For incoming connections, we didn't quite do the same thing. For one, `SwarmEvent::IncomingConnectionError` directly contained a `PendingInboundConnectionError`. Two, `FromSwarm::ListenFailure` did not include an error at all.
With this patch, we now introduce a `ListenError` enum which we use in `SwarmEvent::IncomingConnectionError` and we pass a reference to it along in `FromSwarm::ListenFailure`.
Previously, we used the full reference to the `OutEvent` of the `ConnectionHandler` in all implementations of `NetworkBehaviour`. Not only is this very verbose, it is also more brittle to changes. With the current implementation plan for #2824, we will be removing the `IntoConnectionHandler` abstraction. Using a type-alias to refer to the `OutEvent` makes the migration much easier.
This patch deprecates 3 out of 4 functions on `PollParameters`:
- `local_peer_id`
- `listened_addresses`
- `external_addresses`
The addresses can be obtained by inspecting the `FromSwarm` event. To make this easier, we introduce two utility structs in `libp2p-swarm`:
- `ExternalAddresses`
- `ListenAddresses`
A node's `PeerId` is always known to the caller, thus we can require them to pass it in.
Related: #3124.
Currently, our `NetworkBehaviour` derive macro depends on the `libp2p` crate to be in scope. This prevents standalone usage which forces us to depend on `libp2p` in all our tests where we want to derive a `NetworkBehaviour`.
This PR introduces a `prelude` option that - by default - points to `libp2p::swarm::derive_prelude`, a new module added to `libp2p_swarm`. With this config option, users of `libp2p_swarm` can now refer to the macro without depending on `libp2p`, breaking the circular dependency in our workspace. For consistency with the ecosystem, the macro is now also re-exported by `libp2p_swarm` instead of `libp2p` at the same position as the trait that it implements.
Lastly, we introduce an off-by-default `macros` feature flag that shrinks the dependency tree for users that don't need the derive macro.
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.
Remove the concept of individual `Transport::Listener` streams from `Transport`.
Instead the `Transport` is polled directly via `Transport::poll`. The
`Transport` is now responsible for driving its listeners.
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.
The `ConnectionHandler` trait is not exposed to users. The only
implementor of `ConnectionHandler` is `NodeHandlerWrapper`. Thus
`ConnectionHandler` is a superfluous abstraction. This commit removes
`ConnectionHandler`.
Next to this large change, this commit removes the `Tmuxer` trait
parameter. `Swarm` enforces dynamic dispatching via `StreamMuxerBox`
anyways, thus the trait parameter is useless.
As a follow up to this commit one could rename `ProtocolsHandler` to
`ConnectionHandler` and `NodeHandlerWrapper` to
`ConnectionHandlerWrapper` or just `Wrapper`.
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>
Enable advanced dialing requests both on `Swarm` and via
`NetworkBehaviourAction`. Users can now trigger a dial with a specific
set of addresses, optionally extended via
`NetworkBehaviour::addresses_of_peer`. In addition the whole process is
now modelled in a type safe way via the builder pattern.
Example of a `NetworkBehaviour` requesting a dial to a specific peer
with a set of addresses additionally extended through
`NetworkBehaviour::addresses_of_peer`:
```rust
NetworkBehaviourAction::Dial {
opts: DialOpts::peer_id(peer_id)
.condition(PeerCondition::Always)
.addresses(addresses)
.extend_addresses_through_behaviour()
.build(),
handler,
}
```
Example of a user requesting a dial to an unknown peer with a single
address via `Swarm`:
```rust
swarm1.dial(
DialOpts::unknown_peer_id()
.address(addr2.clone())
.build()
)
```
Concurrently dial address candidates within a single dial attempt.
Main motivation for this feature is to increase success rate on hole punching
(see https://github.com/libp2p/rust-libp2p/issues/1896#issuecomment-885894496
for details). Though, as a nice side effect, as one would expect, it does
improve connection establishment time.
Cleanups and fixes done along the way:
- Merge `pool.rs` and `manager.rs`.
- Instead of manually implementing state machines in `task.rs` use
`async/await`.
- Fix bug where `NetworkBehaviour::inject_connection_closed` is called without a
previous `NetworkBehaviour::inject_connection_established` (see
https://github.com/libp2p/rust-libp2p/issues/2242).
- Return handler to behaviour on incoming connection limit error. Missed in
https://github.com/libp2p/rust-libp2p/issues/2242.
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>
With 45f07bf8639fd9056e4ffe52298ca113a0308951 `Network::dial` accepts a
`Multiaddr` with a `PeerId`. With that in mind the doc comment on
`NetworkBehaviourAction::DialAddress` is outdated.
Not all implementations of `NetworkBehaviour` need all callbacks.
We've have been adding new callbacks with default implementations
for a while now. There is no reason the initial ones cannot also
be defaulted, thus making it easier create new implementations.
Co-authored-by: Max Inden <mail@max-inden.de>
Add `ExpandedSwarm::disconnect_peer_id` and
`NetworkBehaviourAction::CloseConnection` to close connections to a specific
peer via an `ExpandedSwarm` or `NetworkBehaviour`.
Co-authored-by: Max Inden <mail@max-inden.de>
`NetworkBehaviour::inject_connected` is called for the first established
connection to a peer only. See `swarm/src/lib.rs`:
```rust
this.behaviour.inject_connection_established(&peer_id, &connection.id(), &endpoint);
if num_established.get() == 1 {
this.behaviour.inject_connected(&peer_id);
}
```
This commit adjusts the documentation accordingly.
Remove `NotifyHandler::All` thus removing the requirement for events
send from a `NetworkBehaviour` to a `ProtocolsHandler` to be `Clone`. An
implementor of `NetworkBehaviour` can still notify all
`ProtocolHandler`s for a given peer by emitting one `NotifyHandler`
event per connection to that peer.
* Add "infinite" scores for external addresses.
Extend address scores with an infinite cardinal, permitting
addresses to be retained "forever" or until explicitly removed.
Expose (external) address scores on the API.
* Update swarm/src/registry.rs
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>
* Fix compilation.
* Update CHANGELOG
Co-authored-by: Pierre Krieger <pierre.krieger1708@gmail.com>
* Use a single exchange instead of two one_shots.
* Add `Throttled` to libp2p-request-response.
Wraps the existing `RequestResponse` behaviour and applies strict limits
to the number of inbound and outbound requests per peer.
The wrapper is opt-in and if not used, the protocol behaviour of
`RequestResponse` does not change. This PR also does not introduce
an extra protocol, hence the limits applied need to be known a priori
for all nodes which is not always possible or desirable. As mentioned
in #1687 I think that we should eventually augment the protocol with
metadata which allows a more dynamic exchange of requests and responses.
This PR also replaces the two oneshot channels with a single one from the
scambio crate which saves one allocation per request/response. If not
desirable because the crate has seen less testing the first commit could
be reverted.
* Fix rustdoc error.
* Remove some leftovers from development.
* Add docs to `NetworBehaviourAction::{map_in,map_out}`.
* Apply suggestions from code review
Co-authored-by: Roman Borschel <romanb@users.noreply.github.com>
* Add `ping_protocol_throttled` test.
* Add another test.
* Revert "Use a single exchange instead of two one_shots."
This reverts commit e34e1297d411298f6c69e238aa6c96e0b795d989.
# Conflicts:
# protocols/request-response/Cargo.toml
# protocols/request-response/src/handler/protocol.rs
* Update CHANGELOG.
* Update CHANGELOG.
Co-authored-by: Roman Borschel <romanb@users.noreply.github.com>
