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, 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.
With this patch, implementations of `ConnectionHandler` (which are typically composed in a tree) can exchange information about the supported protocols of a remote with each other via `ConnectionHandlerEvent::ReportRemoteProtocols`. The provided `ProtocolSupport` enum can describe either additions or removals of the remote peer's protocols.
This information is aggregated in the connection and passed down to the `ConnectionHandler` via `ConnectionEvent::RemoteProtocolsChange`.
Similarly, if the listen protocols of a connection change, all `ConnectionHandler`s on the connection will be notified via `ConnectionEvent::LocalProtocolsChange`. This will allow us to eventually remove `PollParameters` from `NetworkBehaviour`.
This pattern allows protocols on a connection to communicate with each other. For example, protocols like identify can share the list of (supposedly) supported protocols by the remote with all other handlers. A protocol like kademlia can accurately add and remove a remote from its routing table as a result.
Resolves: #2680.
Related: #3124.
Pull-Request: #3651.
Users are encouraged to use `libp2p::connection_limit::Behaviour` which is a one-to-one replacement for this functionality but built as a `NetworkBehaviour`.
Related: #3647.
Pull-Request: #3885.
The currently provided `ConnectionHandlerUpgrErr` is very hard to use. Not only does it have a long name, it also features 3 levels of nesting which results in a lot of boilerplate. Last but not least, it exposes `multistream-select` as a dependency to all protocols.
We fix all of the above by renaming the type to `StreamUpgradeError` and flattening out its interface. Unrecoverable errors during protocol selection are hidden within the `Io` variant.
Related: #3759.
Pull-Request: #3882.
This removes the deprecated `IntoConnectionHandler` trait and all its implementations. Consequently, `NetworkBehaviour::new_handler` and `NetworkBehaviour::addresses_of_peer` are now gone and the two `handle_` functions are now required to implement.
Related: #3647.
Pull-Request: #3884.
Previously, a protocol could be any sequence of bytes as long as it started with `/`. Now, we directly parse a protocol as `String` which enforces it to be valid UTF8.
To notify users of this change, we delete the `ProtocolName` trait. The new requirement is that users need to provide a type that implements `AsRef<str>`.
We also add a `StreamProtocol` newtype in `libp2p-swarm` which provides an easy way for users to ensure their protocol strings are compliant. The newtype enforces that protocol strings start with `/`. `StreamProtocol` also implements `AsRef<str>`, meaning users can directly use it in their upgrades.
`multistream-select` by itself only changes marginally with this patch. The only thing we enforce in the type-system is that protocols must implement `AsRef<str>`.
Resolves: #2831.
Pull-Request: #3746.
This tiny PR contains a proposed change for the warning related to the exceeded pending incoming connections limit. This warning can't be controlled and causes user confusion. It contains useful technical info but IMHO should be downgraded from `warn` to `debug`.
Pull-Request: #3671.
Currently, banning peers is a first-class feature of `Swarm`. With the new connection management capabilities of `NetworkBehaviour`, we can now implement allow and block lists as a separate module.
We introduce a new crate `libp2p-allow-block-list` and deprecate `Swarm::ban_peer_id` in favor of that.
Related #2824.
Pull-Request: #3590.
This patch deprecates the existing connection limits within `Swarm` and uses the new `NetworkBehaviour` APIs to implement it as a plugin instead.
Related #2824.
Pull-Request: #3386.
Mark constructors `Swarm::with_X_executor` as deprecated.
Move the deprecated functionality to `SwarmBuilder::with_X_executor`
Use `SwarmBuilder` throughout.
Resolves#3186.
Resolves#3107.
Pull-Request: #3588.
This patch-set introduces `libp2p-swarm-test`. It provides utilities for quick and safe bootstrapping of tests for `NetworkBehaviour`s. The main design features are:
- Everything has timeouts
- APIs don't get in your way
- Minimal boilerplate
Closes#2884.
Pull-Request: #2888.
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.
This commit does two things:
- Check that swarm1, given that it has no ban, establishes 21 connections and swarm2, given that it has a ban, establishes 20 connections.
- Wait for swarm1 to notice disconnect, given that swarm2 closed the connection to the banned swarm1.
Fixes flake introduced in caed1fe2c7.
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.
Previously, inbound connections that happened to resolve to our own `PeerId` were reported as `WrongPeerId`. With this patch, we now report those in a dedicated `LocalPeerId` error.
Related: #3205.
The trick with this one is to use `futures::Either` everywhere where we may wrap something that implements any of the `futures` traits. This includes the output of `EitherFuture` itself. We also need to implement `StreamMuxer` on `future::Either` because `StreamMuxer`s may be the the `Output` of `InboundUpgrade`.
Currently, we only have a single channel for all established connections. This requires us to construct the channel ahead of time, before we even have a connection. As it turns out, sharing this buffer across all connections actually has downsides. In particular, this means a single, very busy connection can starve others by filling up this buffer, forcing other connections to wait until they can emit an event.
Ever since we moved `Pool` into `libp2p-swarm`, we always use it with the same `Transport`: `Boxed`. It is thus unnecessary for us to be overly generic over what kind of `Transport` we are using. This allows us to remove a few type parameters from the implementation which overall simplifies things.
This is technically a breaking change because I am removing a type parameter from two exported type aliases:
- `PendingInboundConnectionError`
- `PendingOutboundConnectionError`
Those have always only be used with `std::io::Error` in our API but it is still a breaking change.
Previously, the logic within `Swarm::dial` involved fairly convoluted `match` expressions. This patch refactors this function to use new utility functions introduced on `DialOpts` to handle one concern at a time.
This has the advantage that we are covering slightly more cases now. Because we are parsing the `PeerId` only once at the top, checks like banning will now also act on dials that specify the `PeerId` as part of the `/p2p` protocol.
As I do frequently, I corrected for the latest clippy warnings. This will make sure the CI won't complain in the future. We could automate this btw and maybe run the nightly version of clippy.
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.
In case support for e.g. RSA keys is disabled at compile-time, we will now print a better error message. For example:
> Failed to dial Some(PeerId("QmcZf59bWwK5XFi76CZX8cbJ4BhTzzA3gU1ZjYZcYW3dwt")): Failed to negotiate transport protocol(s): [(/dnsaddr/bootstrap.libp2p.io/p2p/QmcZf59bWwK5XFi76CZX8cbJ4BhTzzA3gU1ZjYZcYW3dwt): : Handshake failed: Handshake failed: Invalid public key: Key decoding error: RSA keys are unsupported)]
Fixes#2971.
We refactor our continuous integration workflow with the following goals in mind:
- Run as few jobs as possible
- Have the jobs finish as fast as possible
- Have the jobs redo as little work as possible
There are only so many jobs that GitHub Actions will run in parallel.
Thus, it makes sense to not create massive matrices but instead group
things together meaningfully.
The new `test` job will:
- Run once for each crate
- Ensure that the crate compiles on its specified MSRV
- Ensure that the tests pass
- Ensure that there are no semver violations
This is an improvement to before because we are running all of these
in parallel which speeds up execution and highlights more errors at
once. Previously, tests run later in the pipeline would not get run
at all until you make sure the "first" one passes.
We also previously did not verify the MSRV of each crate, making the
setting in the `Cargo.toml` rather pointless.
The new `cross` job supersedes the existing `wasm` job.
This is an improvement because we now also compile the crate for
windows and MacOS. Something that wasn't checked before.
We assume that checking MSRV and the tests under Linux is good enough.
Hence, this job only checks for compile-errors.
The new `feature_matrix` ensures we compile correctly with certain feature combinations.
`libp2p` exposes a fair few feature-flags. Some of the combinations
are worth checking independently. For the moment, this concerns only
the executor related transports together with the executor flags but
this list can easily be extended.
The new `clippy` job runs for `stable` and `beta` rust.
Clippy gets continuously extended with new lints. Up until now, we would only
learn about those as soon as a new version of Rust is released and CI would
run the new lints. This leads to unrelated failures in CI. Running clippy on with `beta`
Rust gives us a heads-up of 6 weeks before these lints land on stable.
Fixes#2951.
