Crate libp2p::request_response

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Generic request/response protocols.

§General Usage

The Behaviour struct is a NetworkBehaviour that implements a generic request/response protocol or protocol family, whereby each request is sent over a new substream on a connection. Behaviour is generic over the actual messages being sent, which are defined in terms of a Codec. Creating a request/response protocol thus amounts to providing an implementation of this trait which can then be given to Behaviour::with_codec. Further configuration options are available via the Config.

Requests are sent using Behaviour::send_request and the responses received as Message::Response via Event::Message.

Responses are sent using Behaviour::send_response upon receiving a Message::Request via Event::Message.

§Predefined codecs

In case your message types implement [serde::Serialize] and [serde::Deserialize], you can use two predefined behaviours:

  • [cbor::Behaviour] for CBOR-encoded messages
  • [json::Behaviour] for JSON-encoded messages

§Protocol Families

A single Behaviour instance can be used with an entire protocol family that share the same request and response types. For that purpose, Codec::Protocol is typically instantiated with a sum type.

§Limited Protocol Support

It is possible to only support inbound or outbound requests for a particular protocol. This is achieved by instantiating Behaviour with protocols using ProtocolSupport::Inbound or ProtocolSupport::Outbound. Any subset of protocols of a protocol family can be configured in this way. Such protocols will not be advertised during inbound respectively outbound protocol negotiation on the substreams.

Structs§

  • Behaviour
    A request/response protocol for some message codec.
  • Config
    The configuration for a Behaviour protocol.
  • RequestId
    The ID of an inbound or outbound request.
  • ResponseChannel
    A channel for sending a response to an inbound request.

Enums§

  • Event
    The events emitted by a request-response Behaviour.
  • InboundFailure
    Possible failures occurring in the context of receiving an inbound request and sending a response.
  • Message
    An inbound request or response.
  • OutboundFailure
    Possible failures occurring in the context of sending an outbound request and receiving the response.
  • ProtocolSupport
    The level of support for a particular protocol.

Traits§

  • Codec
    A Codec defines the request and response types for a request-response Behaviour protocol or protocol family and how they are encoded / decoded on an I/O stream.