This option is the only reason we pull in a dependency on the shared `zlib` library. Unfortunately, we cannot use a pure Rust backend here because that one does not support configuring the window bits of the deflate algorithm which is used in the deflate websocket extension.
Using websockets in libp2p is already crazy inefficient because you end up with double encryption when using `/wss` (which is enforced by browsers if your website is served via https). A good encryption algorithm like noise or TLS produces an output that looks completely random. Any attempt in compressing this is pretty much wasted CPU power.
Thus, I think removing this configuration option does not really hurt and allows us to remove the dependency on the `zlib` shared library.
Pull-Request: #3949.
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.
By using a multi-stage docker build, a distroless base image and a release build, we can get the size of the Rust interop test down to 50MB. Previously, the image would be around 500MB. A debug build image would still have ~400MB. The release build slows down our interop build step by about 1min 20s. That however is only because we don't currently seem to utilize the caches that from what I understand should work on self-hosted runners. I opted https://github.com/libp2p/rust-libp2p/issues/3925 for that.
Resolves: #3881.
Pull-Request: #3926.
Previously we would increase a counter / gauge / histogram on each received identify information. These metrics are missleading, as e.g. they depend on the identify interval and don't represent the set of currently connected peers.
With this commit, identify information is tracked for the currently connected peers only. Instead of an increase on each received identify information, metrics represent the status quo (Gauge).
Example:
```
\# HELP libp2p_libp2p_identify_remote_protocols Number of connected nodes supporting a specific protocol, with "unrecognized" for each peer supporting one or more unrecognized protocols...
\# TYPE libp2p_libp2p_identify_remote_protocols gauge
libp2p_libp2p_identify_remote_protocols_total{protocol="/ipfs/id/push/1.0.0"} 1
libp2p_libp2p_identify_remote_protocols_total{protocol="/ipfs/id/1.0.0"} 1
libp2p_libp2p_identify_remote_protocols_total{protocol="/ipfs/ping/1.0.0"} 1
libp2p_libp2p_identify_remote_protocols_total{protocol="unrecognized"} 1
\# HELP libp2p_libp2p_identify_remote_listen_addresses Number of connected nodes advertising a specific listen address...
\# TYPE libp2p_libp2p_identify_remote_listen_addresses gauge
libp2p_libp2p_identify_remote_listen_addresses_total{listen_address="/ip4/tcp"} 1
libp2p_libp2p_identify_remote_listen_addresses_total{listen_address="/ip4/udp/quic"} 1
\# HELP libp2p_libp2p_identify_local_observed_addresses Number of connected nodes observing the local node at a specific address...
\# TYPE libp2p_libp2p_identify_local_observed_addresses gauge
libp2p_libp2p_identify_local_observed_addresses_total{observed_address="/ip4/tcp"} 1
```
Pull-Request: #3325.
Previously, we used to race the two identify responses and assert the one that finished earlier. In practice, this didn't work but sometimes caused a timeout. See https://github.com/libp2p/rust-libp2p/actions/runs/4973490081/jobs/8899378998#step:7:98 for an example.
Interestingly enough, refactoring this test to always assert both responses reveals a bug! The memory transport by default behaves like TCP and allocates a new ephemeral port for an outgoing connection. I believe this was never hit because the first swarm would always receive its response first and win the race.
To assert this properly, we would have to implement port reuse for the memory transport which I think is unnecessary, hence I just commented out the assertion.
Pull-Request: #3924.
Previously, we used to race the two identify responses and assert the one that finished earlier. In practice, this didn't work but sometimes caused a timeout. See https://github.com/libp2p/rust-libp2p/actions/runs/4973490081/jobs/8899378998#step:7:98 for an example.
Interestingly enough, refactoring this test to always assert both responses reveals a bug! The memory transport by default behaves like TCP and allocates a new ephemeral port for an outgoing connection. I believe this was never hit because the first swarm would always receive its response first and win the race.
To assert this properly, we would have to implement port reuse for the memory transport which I think is unnecessary, hence I just commented out the assertion.
Pull-Request: #3924.
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 set of changes, we prepare the public API of `libp2p-yamux` to be as minimal as possible and allow for upgrades of the underlying `yamux` library in patch releases.
Related: #3013.
Pull-Request: #3908.
Previously, this function would return an error in case the provided digest is not of 32 bytes long. As per our [spec](https://github.com/libp2p/specs/blob/master/peer-ids/peer-ids.md#secp256k1), we hash _all_ messages with SHA256 before signing, thus this error can never happen in practice.
This brings us one step closer to an infallible `Keypair::sign` which is now only fallible due to RSA signing. If we manage to fix that as well, constructors like `noise::Config::new` will become infallible.
Pull-Request: #3850.
I noticed that we also still leak that dependency in several crates by providing a `From` impl so I've removed that one as well.
Resolves#3534.
Pull-Request: #3894.
A `ConnectionHandler` is bound to a single peer. There is no need to embed the `PeerId` in the event that we report to the behaviour, it already knows which peer the event relates to.
Pull-Request: #3895.
This patch removes the 3 out of 4 deprecated public modules. I've left `store` for now because we made some mistakes in declaring that. The items within `store` still need to be publicly visible but I haven't yet figured out a good way of exporting / naming them. Thus, I've left that to a follow-up PR.
Related: #3647.
Pull-Request: #3896.
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.
Currently, the `connection_keep_alive` function of identify does not compute anything but its return value is set through the handler state machine. This is hard to understand and causes surprising behaviour because at the moment, we set `KeepAlive::No` as soon as the remote has answered our identify request. Depending on what else is happening on the connection, this might close the connection before we have successfully answered the remote's identify request.
To fix this, we now compute `connection_keep_alive` based on whether we are still using the connection.
Related: #3844.
Pull-Request: #3876.
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.
This patch removes all deprecated legacy code from `libp2p-noise` and attempts to collapse all the abstraction layers into something a lot simpler.
Pull-Request: #3511.
