Crate libp2p_request_response

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.

Modules

• cborcbor
• jsonjson

Structs

• Behaviour
  A request/response protocol for some message codec.
• Config
  The configuration for a Behaviour protocol.
• InboundRequestId
  The ID of an inbound request.
• OutboundRequestId
  The ID of an 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.