Previously, a connection would be shut down immediately as soon as its `ConnectionHandler` reports `KeepAlive::No`. As we have gained experience with libp2p, it turned out that this isn't ideal.
For one, tests often need to keep connections alive longer than the configured protocols require. Plus, some usecases require connections to be kept alive in general.
Both of these needs are currently served by the `keep_alive::Behaviour`. That one does essentially nothing other than statically returning `KeepAlive::Yes` from its `ConnectionHandler`.
It makes much more sense to deprecate `keep_alive::Behaviour` and instead allow users to globally configure an `idle_conncetion_timeout` on the `Swarm`. This timeout comes into effect once a `ConnectionHandler` reports `KeepAlive::No`. To start with, this timeout is 0. Together with https://github.com/libp2p/rust-libp2p/issues/3844, this will allow us to move towards a much more aggressive closing of idle connections, together with a more ergonomic way of opting out of this behaviour.
Fixes#4121.
Pull-Request: #4161.
This PR changes the logging of the Kademlia connection handler related to the remote Kademlia mode changes:
- Downgrade log level for the remote kademlia protocol report from `info` to `debug`.
- Introduce connection_id for the handler to improve logging.
Pull-Request: #4278.
The display of `ListenError` could be more helpful. The inner `cause` already implements `Error` which in turn requires `Display`. This is then just a matter of using said impl requirement to get an useful display
Pull-Request: #4232.
Using workspace inheritance breaks `cargo release` because it cannot resolve that the dev-dependencies should only use a `path` and not a version.
Pull-Request: #4097.
Co-Authored-By: Thomas Eizinger <thomas@eizinger.io>
We have two "interface" crates in our workspace: `libp2p-core` and `libp2p-swarm`. Most crates depend on both of these. To compile the tests for this crate, we often need a concrete implementation to some of these interfaces. When specifying a workspace-inherited dependency, we don't get to choose to omit the `version` field next to the path. If a dependency is `path`-only however, it will be tripped by `cargo` during the release process which is why all of this worked before our move to workspace inheritance.
With this patch, we change the minimum amount of dependencies necessary back to `path` dependencies to allowing releasing of our crates.
Related: #4053.
Pull-Request: #4091.
Co-Authored-By: Thomas Eizinger <thomas@eizinger.io>
Prior to this change it was only possible to downcast a `ConnectionDenied` error when you had ownership of it which isn't the case inside `NetworkBehaviour`s. This change allows downcasting by reference.
See https://github.com/libp2p/rust-libp2p/discussions/4018.
Pull-Request: #4020.
This extends `ToSwarm` to add `ToSwarm::ListenOn` and `ToSwarm::RemoveListener`, which allows creating and removing listeners from a `NetworkBehaviour`.
Resolves https://github.com/libp2p/rust-libp2p/issues/3291.
Pull-Request: #3292.
In the unlikely event that we generated a random number twice, the 2nd address would not get added. Ensure we loop until we have 20 addresses.
Pull-Request: #4030.
Currently, the kademlia behaviour can only learn that the remote node supports kademlia on a particular connection if we successfully negotiate a stream to them.
Using the newly introduced abstractions from #3651, we don't have to attempt to establish a stream to the remote to learn whether they support kademlia on a connection but we can directly learn it from the `ConnectionEvent::RemoteProtocolsChange` event. This happens directly once a connection is established which should overall benefit the DHT.
Clients do not advertise the kademlia protocol and thus we will immediately learn that a given connection is not suitable for kadmelia requests. We may receive inbound messages from it but this does not affect the routing table.
Resolves: #2032.
Pull-Request: #3877.
This modification removes deprecated dependency `wasm_timer` and enables wasm compatibility on the gossibsup protocol by simply substituting the `wasm_timer::Instant` with `instant::Instant`(which supports `fn checked_add`) and `wasm_timer::Interval` with `futures_ticker::Ticker`.
Pull-Request: #3973.
Previously, the `libp2p-ping` module came with a policy to close a connection after X failed pings. This is only one of many possible policies on how users would want to do connection management.
We remove this policy without a replacement. If users wish to restore this functionality, they can easily implement such policy themselves: The default value of `max_failures` was 1. To restore the previous functionality users can simply close the connection upon the first received ping error.
In this same patch, we also simplify the API of `ping::Event` by removing the layer of `ping::Success` and instead reporting the RTT to the peer directly.
Related: #3591.
Pull-Request: #3947.
Previously, a `NetworkBehaviour` could report an `AddressScore` for an external address. This score was a `u32` and addresses would be ranked amongst those.
In reality, an address is either confirmed to be publicly reachable (via a protocol such as AutoNAT) or merely represents a candidate that might be an external address. In a way, addresses are guilty (private) until proven innocent (publicly reachable).
When a `NetworkBehaviour` reports an address candidate, we perform address translation on it to potentially correct for ephemeral ports of TCP. These candidates are then injected back into the `NetworkBehaviour`. Protocols such as AutoNAT can use these addresses as a source for probing their NAT status. Once confirmed, they can emit a `ToSwarm::ExternalAddrConfirmed` event which again will be passed to all `NetworkBehaviour`s.
This simplified approach will allow us implement Kademlia's client-mode (https://github.com/libp2p/rust-libp2p/issues/2032) without additional configuration options: As soon as an address is reported as publicly reachable, we can activate server-mode for that connection.
Related: https://github.com/libp2p/rust-libp2p/pull/3877.
Related: https://github.com/libp2p/rust-libp2p/issues/3953.
Related: https://github.com/libp2p/rust-libp2p/issues/2032.
Related: https://github.com/libp2p/go-libp2p/issues/2229.
Co-authored-by: Max Inden <mail@max-inden.de>
Pull-Request: #3954.
Previously, we would not call the handler upon injecting `ConnectionEvent::LocalProtocolsChange`. This would prevent protocols from being able to react to this change and e.g. issue events or open streams.
Pull-Request: #3979.
This PR refactors the error reporting away from panicking to returning `syn::Result` and adds two unit tests for the parsing of attributes that users interact with.
Pull-Request: #3922.
Previously, the associated types on `NetworkBehaviour` and `ConnectionHandler` carried generic names like `InEvent` and `OutEvent`. These names are _correct_ in that `OutEvent`s are passed out and `InEvent`s are passed in but they don't help users understand how these types are used.
In theory, a `ConnectionHandler` could be used separately from `NetworkBehaviour`s but that is highly unlikely. Thus, we rename these associated types to indicate, where the message is going to be sent to:
- `NetworkBehaviour::OutEvent` is renamed to `ToSwarm`: It describes the message(s) a `NetworkBehaviour` can emit to the `Swarm`. The user is going to receive those in `SwarmEvent::Behaviour`.
- `ConnectionHandler::InEvent` is renamed to `FromBehaviour`: It describes the message(s) a `ConnectionHandler` can receive from its behaviour via `ConnectionHandler::on_swarm_event`. The `NetworkBehaviour` can send it via the `ToSwarm::NotifyHandler` command.
- `ConnectionHandler::OutEvent` is renamed to `ToBehaviour`: It describes the message(s) a `ConnectionHandler` can send back to the behaviour via the now also renamed `ConnectionHandlerEvent::NotifyBehaviour` (previously `ConnectionHandlerEvent::Custom`)
Resolves: #2854.
Pull-Request: #3848.
`Transport::listen_on` is an asynchronous operation. It returns immediately but the actual process of establishing a listening socket happens as part of `Transport::poll` which will return one or more `TransportEvent`s related to a particular `listen_on` call.
Currently, `listen_on` returns a `ListenerId` which allows the user of the `Transport` interface to correlate the events with a particular `listen_on` call. This "user" is the `Swarm` runtime. Currently, a user of libp2p establishes a new listening socket by talking to the `Swarm::listen_on` interface and it is not possible to do the same thing via the `NetworkBehaviour` trait.
Within the `NetworkBehaviour` trait, we emit _commands_ to the `Swarm` like `ToSwarm::Dial`. These commands don't have a "return value" like a synchronous function does and thus, if we were to add a `ToSwarm::ListenOn` command, it could not receive the `ListenerId` from the `Transport`.
To fix this and to be consistent with our [coding guidelines](https://github.com/libp2p/rust-libp2p/blob/master/docs/coding-guidelines.md#allow-correlating-asynchronous-responses-to-their-requests) we change the interface of `Transport::listen_on` to require the user to pass in a `ListenerId`. This will allow us to construct a command in a `NetworkBehaviour` that remembers this ID which enables precise tracking of which events containing a `ListenerId` correlate which a particular `listen_on` command.
This is especially important in the context of listening on wildcard addresses like `0.0.0.0` because we end up binding to multiple network interfaces and thus emit multiple events for a single `listen_on` call.
Pull-Request: #3567.
This patch tackles two things at once that are fairly intertwined:
1. There is no such thing as a "substream" in libp2p, the spec and other implementations only talk about "streams". We fix this by deprecating `NegotiatedSubstream`.
2. Previously, `NegotiatedSubstream` was a type alias that pointed to a type from `multistream-select`, effectively leaking the version of `multistream-select` to all dependencies of `libp2p-swarm`. We fix this by introducing a `Stream` newtype.
Resolves: #3759.
Related: #3748.
Pull-Request: #3912.
