go-multistream

an implementation of the multistream protocol in go

This package implements a simple stream router for the multistream-select protocol. The protocol is defined here.

Table of Contents

• Install
• Usage
• Maintainers
• Contribute
• License

Install

go-multistream is a standard Go module which can be installed with:

go get github.com/multiformats/go-multistream

Usage

Example

This example shows how to use a multistream muxer. A muxer uses user-added handlers to handle different "protocols". The first step when interacting with a connection handler by the muxer is to select the protocol (the example uses SelectProtoOrFail). This will then let the muxer use the right handler.

package main

import (
	"fmt"
	"io"
	"io/ioutil"
	"net"

	ms "github.com/multiformats/go-multistream"
)

// This example creates a multistream muxer, adds handlers for the protocols
// "/cats" and "/dogs" and exposes it on a localhost:8765. It then opens connections
// to that port, selects the protocols and tests that the handlers are working.
func main() {
	mux := ms.NewMultistreamMuxer[string]()
	mux.AddHandler("/cats", func(proto string, rwc io.ReadWriteCloser) error {
		fmt.Fprintln(rwc, proto, ": HELLO I LIKE CATS")
		return rwc.Close()
	})
	mux.AddHandler("/dogs", func(proto string, rwc io.ReadWriteCloser) error {
		fmt.Fprintln(rwc, proto, ": HELLO I LIKE DOGS")
		return rwc.Close()
	})

	list, err := net.Listen("tcp", ":8765")
	if err != nil {
		panic(err)
	}

	go func() {
		for {
			con, err := list.Accept()
			if err != nil {
				panic(err)
			}

			go mux.Handle(con)
		}
	}()

	// The Muxer is ready, let's test it
	conn, err := net.Dial("tcp", ":8765")
	if err != nil {
		panic(err)
	}

	// Create a new multistream to talk to the muxer
	// which will negotiate that we want to talk with /cats
	mstream := ms.NewMSSelect(conn, "/cats")
	cats, err := ioutil.ReadAll(mstream)
	if err != nil {
		panic(err)
	}
	fmt.Printf("%s", cats)
	mstream.Close()

	// A different way of talking to the muxer
	// is to manually selecting the protocol ourselves
	conn, err = net.Dial("tcp", ":8765")
	if err != nil {
		panic(err)
	}
	defer conn.Close()
	err = ms.SelectProtoOrFail("/dogs", conn)
	if err != nil {
		panic(err)
	}
	dogs, err := ioutil.ReadAll(conn)
	if err != nil {
		panic(err)
	}
	fmt.Printf("%s", dogs)
	conn.Close()
}

Contribute

Contributions welcome. Please check out the issues.

Check out our contributing document for more information on how we work, and about contributing in general. Please be aware that all interactions related to multiformats are subject to the IPFS Code of Conduct.

Small note: If editing the README, please conform to the standard-readme specification.

License

MIT © 2016 Jeromy Johnson