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.
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.
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.
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.
Previously, we had one callback for each kind of message that a `ConnectionHandler` would receive from either its `NetworkBehaviour` or the connection itself.
With this patch, we combine these functions, resulting in two callbacks:
- `on_behaviour_event`
- `on_connection_event`
Resolves#3080.
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.
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.
Changes needed to get libp2p to run via `wasm32-unknown-unknown` in the browser
(both main thread and inside web workers).
Replaces wasm-timer with futures-timer and instant.
Co-authored-by: Oliver Wangler <oliver@wngr.de>
Don't close connection if ping protocol is unsupported by remote. Previously, a
failed protocol negotation for ping caused a force close of the connection. As a
result, all nodes in a network had to support ping. To allow networks where some
nodes don't support ping, we now emit `PingFailure::Unsupported` once for every
connection on which ping is not supported.
Co-authored-by: Max Inden <mail@max-inden.de>
* Refactor the ping protocol.
Such that pings are sent over a single substream, as it is
done in other libp2p implementations. Note that, since each
peer sends its pings over a single, dedicated substream,
every peer that participates in the protocol has effectively
two open substreams.
* Cleanup
* Update ping changelog.
* Update protocols/ping/src/protocol.rs
Co-authored-by: Max Inden <mail@max-inden.de>
Co-authored-by: Max Inden <mail@max-inden.de>
* Fix broken links in rustdoc
This fixes all of the rustdoc warnings on nightly.
* Check documentation intra-link
* Fix config
* Fix bad indent
* Make nightly explicit
* More links fixes
* Fix link broken after master merge
Co-authored-by: Demi Obenour <48690212+DemiMarie-parity@users.noreply.github.com>
* Simplify trait bounds requirements
* More work
* Moar
* Finish
* Fix final tests
* More simplification
* Use separate traits for Inbound/Outbound
* Update gossipsub and remove warnings
* Add documentation to swarm
* Remove BoxSubstream
* Fix tests not compiling
* Fix stack overflow
* Address concerns
* For some reason my IDE ignored libp2p-kad
- Pin `futures_codec` to version 0.3.3 as later versions require
at least bytes-0.5 which he have not upgraded to yet.
- Replace `futures::executor::block_on` with `async_std::task::block_on`
where `async-std` is already a dependency to work around an issue with
`park`/`unpark` behaviour.
- Use the published version of `quicksink`.
This is now a very simple option serving multiple purposes:
* It allows for stable (integration) tests involving a Swarm, which
are otherwise subject to race conditions due to the connection being
allowed to terminate at any time with `KeepAlive::No`
(which remains the default).
* It makes for a more entertaining ping example which continuously
sends pings.
* Maybe someone wants to use the ping protocol for application-layer
connection keep-alive after all.
* Fix connection & handler shutdown when using `KeepAlive::Now`.
Delay::new(Instant::now()) is never immediately ready, resulting in
`KeepAlive::Now` to have no effect, since the delay is re-created on
every execution of `poll()` in the `NodeHandlerWrapper`. It can also
send the node handler into a busy-loop, since every newly
created Delay will trigger a task wakeup, which creates a new Delay
with Instant::now(), and so forth.
The use of `Delay::new(Instant::now())` for "immediate" connection shutdown
is therefore removed here entirely. An important assumption is thereby
that as long as the node handler non-empty `negotiating_in` and `negotiating_out`,
the handler is not dependent on such a Delay for task wakeup.
* Correction to the libp2p-ping connection timeout.
The current connection timeout is always short of one `interval`,
because the "countdown" begins with the last received or sent pong
(depending on the policy). In effect, the current default config has
a connection timeout of 5 seconds (20 - 15) from the point when a ping is sent.
Instead, the "countdown" of the connection timeout should always begin
with the next scheduled ping. That also makes all configurations valid,
avoiding pitfalls.
The important properties of the ping handler are now checked to hold for all
configurations, in particular:
* The next ping must be scheduled no earlier than the ping interval
and no later than the connection timeout.
* The "countdown" for the connection timeout starts on the next ping,
i.e. the full connection timeout remains at the instant when the
next ping is sent.
* Do not keep connections alive.
The ping protocol is not supposed to keep otherwise idle connections
alive, only to add an additional condition for terminating them in
the form of a configurable number of consecutive failed ping requests.
In this context, the `PingPolicy` does not seem useful any longer.
* libp2p-ping improvements.
* re #950: Removes use of the `OneShotHandler`, but still sending each
ping over a new substream, as seems to be intentional since #828.
* re #842: Adds an integration test that exercises the ping behaviour through
a Swarm, requiring the RTT to be below a threshold. This requires disabling
Nagle's algorithm as it can interact badly with delayed ACKs (and has been
observed to do so in the context of the new ping example and integration test).
* re #864: Control of the inbound and outbound (sub)stream protocol upgrade
timeouts has been moved from the `NodeHandlerWrapperBuilder` to the
`ProtocolsHandler`. That may also alleviate the need for a custom timeout
on an `OutboundSubstreamRequest` as a `ProtocolsHandler` is now free to
adjust these timeouts over time.
Other changes:
* A new ping example.
* Documentation improvements.
* More documentation improvements.
* Add PingPolicy and ensure no event is dropped.
* Remove inbound_timeout/outbound_timeout.
As per review comment, the inbound timeout is now configured
as part of the `listen_protocol` and the outbound timeout as
part of the `OutboundSubstreamRequest`.
* Simplify and generalise.
Generalise `ListenProtocol` to `SubstreamProtocol`, reusing it in
the context of `ProtocolsHandlerEvent::OutboundSubstreamRequest`.
* Doc comments for SubstreamProtocol.
* Adapt to changes in master.
* Relax upper bound for ping integration test rtt.
For "slow" CI build machines?
