initial tutorial using fork of libp2p

README.md

+use this code to test bring up and exercise libp2p nodes.
+
+usage:
+
+go build -o libp2p-node
+chmod +x libp2p-node
+./libp2p-node

go.mod

+module example.com/hello
+
+go 1.15
+
+require (
+	4d63.com/gochecknoinits v0.0.0-20200108094044-eb73b47b9fc4 // indirect
+	github.com/alecthomas/gocyclo v0.0.0-20150208221726-aa8f8b160214 // indirect
+	github.com/gordonklaus/ineffassign v0.0.0-20210225214923-2e10b2664254 // indirect
+	github.com/jgautheron/goconst v1.4.0 // indirect
+	github.com/libp2p/go-libp2p v0.8.1
+	github.com/libp2p/go-libp2p-core v0.8.4
+	github.com/mdempsky/maligned v0.0.0-20210215075342-f0178ee82032 // indirect
+	github.com/mdempsky/unconvert v0.0.0-20200228143138-95ecdbfc0b5f // indirect
+	github.com/mibk/dupl v1.0.0 // indirect
+	github.com/multiformats/go-multiaddr v0.3.1
+	github.com/opennota/check v0.0.0-20180911053232-0c771f5545ff // indirect
+	github.com/securego/gosec v0.0.0-20200401082031-e946c8c39989 // indirect
+	github.com/tsenart/deadcode v0.0.0-20160724212837-210d2dc333e9 // indirect
+	golang.org/x/lint v0.0.0-20201208152925-83fdc39ff7b5 // indirect
+	mvdan.cc/interfacer v0.0.0-20180901003855-c20040233aed // indirect
+	mvdan.cc/lint v0.0.0-20170908181259-adc824a0674b // indirect
+)
+
+replace github.com/libp2p/go-libp2p v0.8.1 => /home/tavit/Work/dapp/gospace/go1.15.2/src/go-libp2p

main.go

+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/libp2p/go-libp2p"
+	peerstore "github.com/libp2p/go-libp2p-core/peer"
+	"github.com/libp2p/go-libp2p/p2p/protocol/ping"
+	multiaddr "github.com/multiformats/go-multiaddr"
+)
+
+func main() {
+	// create a background context (i.e. one that never cancels)
+	ctx := context.Background()
+
+	// start a libp2p node that listens on TCP port 2000 on the IPv4
+	// loopback interface
+	node, err := libp2p.New(ctx,
+		// libp2p.ListenAddrStrings("/ip4/127.0.0.1/tcp/2000"),
+		libp2p.ListenAddrStrings("/ip4/127.0.0.1/tcp/0"),
+		libp2p.Ping(false),
+	)
+	if err != nil {
+		panic(err)
+	}
+
+	// configure our own ping protocol
+	pingService := &ping.PingService{Host: node}
+	node.SetStreamHandler(ping.ID, pingService.PingHandler)
+
+	// print the node's PeerInfo in multiaddr format
+	peerInfo := peerstore.AddrInfo{
+		ID:    node.ID(),
+		Addrs: node.Addrs(),
+	}
+	addrs, err := peerstore.AddrInfoToP2pAddrs(&peerInfo)
+	fmt.Println("libp2p node address:", addrs[0])
+	fmt.Println("libp2p node ID:", node.ID())
+	fmt.Println("libp2p node Host:", node.Mux())
+
+	// if a remote peer has been passed on the command line, connect to it
+	// and send it 5 ping messages, otherwise wait for a signal to stop
+	if len(os.Args) > 1 {
+		addr, err := multiaddr.NewMultiaddr(os.Args[1])
+		if err != nil {
+			panic(err)
+		}
+		peer, err := peerstore.AddrInfoFromP2pAddr(addr)
+		if err != nil {
+			panic(err)
+		}
+		if err := node.Connect(ctx, *peer); err != nil {
+			panic(err)
+		}
+		fmt.Println("sending 5 ping messages to", addr)
+		ch := pingService.Ping(ctx, peer.ID)
+		for i := 0; i < 5; i++ {
+			res := <-ch
+			fmt.Println("got ping response!", "RTT:", res.RTT)
+		}
+	} else {
+		// wait for a SIGINT or SIGTERM signal
+		ch := make(chan os.Signal, 1)
+		signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM)
+		<-ch
+		fmt.Println("Received signal, shutting down...")
+	}
+
+	// shut the node down
+	if err := node.Close(); err != nil {
+		panic(err)
+	}
+}