1  // Simple libp2p QUIC server for testing
 2  // Run: go run main.go
 3  package main
 4  
 5  import (
 6  	"context"
 7  	"fmt"
 8  	"log"
 9  	"os"
10  	"os/signal"
11  	"syscall"
12  
13  	"github.com/libp2p/go-libp2p"
14  	"github.com/libp2p/go-libp2p/core/network"
15  	"github.com/libp2p/go-libp2p/core/peer"
16  	"github.com/multiformats/go-multiaddr"
17  )
18  
19  func main() {
20  	ctx, cancel := context.WithCancel(context.Background())
21  	defer cancel()
22  
23  	// Create a libp2p host with QUIC transport only
24  	host, err := libp2p.New(
25  		libp2p.ListenAddrStrings(
26  			"/ip4/0.0.0.0/udp/4001/quic-v1",
27  		),
28  		// Disable other transports
29  		libp2p.Transport(libp2p.QUICTransport),
30  	)
31  	if err != nil {
32  		log.Fatalf("Failed to create host: %v", err)
33  	}
34  	defer host.Close()
35  
36  	// Print listening addresses
37  	fmt.Println("libp2p QUIC server started!")
38  	fmt.Printf("Peer ID: %s\n", host.ID())
39  	fmt.Println("Listening on:")
40  	for _, addr := range host.Addrs() {
41  		fmt.Printf("  %s/p2p/%s\n", addr, host.ID())
42  	}
43  	fmt.Println()
44  
45  	// Set up a simple ping handler
46  	host.SetStreamHandler("/ipfs/ping/1.0.0", func(s network.Stream) {
47  		log.Printf("Got ping from %s", s.Conn().RemotePeer())
48  		defer s.Close()
49  		// Echo back
50  		buf := make([]byte, 32)
51  		for {
52  			n, err := s.Read(buf)
53  			if err != nil {
54  				return
55  			}
56  			s.Write(buf[:n])
57  		}
58  	})
59  
60  	// Log connection events
61  	host.Network().Notify(&network.NotifyBundle{
62  		ConnectedF: func(n network.Network, c network.Conn) {
63  			log.Printf("Connected: %s (%s)", c.RemotePeer(), c.RemoteMultiaddr())
64  		},
65  		DisconnectedF: func(n network.Network, c network.Conn) {
66  			log.Printf("Disconnected: %s", c.RemotePeer())
67  		},
68  	})
69  
70  	fmt.Println("Waiting for connections... (Ctrl+C to stop)")
71  
72  	// Wait for interrupt
73  	sigCh := make(chan os.Signal, 1)
74  	signal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
75  	<-sigCh
76  
77  	fmt.Println("\nShutting down...")
78  }