* Remove unused import in rendezvous tests
* Expand uds-transport conditionals to include features
In case neither the tokio nor the async-std feature is defined,
this file needs to be empty to avoid unused code warnings.
Co-authored-by: Max Inden <mail@max-inden.de>
Allows `NetworkBehaviour` implementations to dial a peer, but instruct
the dialed connection to be upgraded as if it were the listening
endpoint.
This is needed when establishing direct connections through NATs and/or
Firewalls (hole punching). When hole punching via TCP (QUIC is different
but similar) both ends dial the other at the same time resulting in a
simultaneously opened TCP connection. To disambiguate who is the dialer
and who the listener there are two options:
1. Use the Simultaneous Open Extension of Multistream Select. See
[sim-open] specification and [sim-open-rust] Rust implementation.
2. Disambiguate the role (dialer or listener) based on the role within
the DCUtR [dcutr] protocol. More specifically the node initiating the
DCUtR process will act as a listener and the other as a dialer.
This commit enables (2), i.e. enables the DCUtR protocol to specify the
role used once the connection is established.
While on the positive side (2) requires one round trip less than (1), on
the negative side (2) only works for coordinated simultaneous dials.
I.e. when a simultaneous dial happens by chance, and not coordinated via
DCUtR, the connection attempt fails when only (2) is in place.
[sim-open]: https://github.com/libp2p/specs/blob/master/connections/simopen.md
[sim-open-rust]: https://github.com/libp2p/rust-libp2p/pull/2066
[dcutr]: https://github.com/libp2p/specs/blob/master/relay/DCUtR.md
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()
)
```
