chore: remove broken example

This example doesn't actually work.

examples/ipfs-camp-2019/04-Protocol/README.md

@@ -1,6 +0,0 @@
-# 04 Protocol
-
-Be sure to check out these modules:
-
-- https://godoc.org/github.com/libp2p/go-libp2p
-- https://godoc.org/github.com/libp2p/go-libp2p-core/host#Host

examples/ipfs-camp-2019/04-Protocol/main.go

@@ -1,76 +0,0 @@
-package main
-
-import (
-	"context"
-	"fmt"
-
-	"github.com/libp2p/go-libp2p"
-	"github.com/libp2p/go-libp2p-core/peer"
-	mplex "github.com/libp2p/go-libp2p-mplex"
-	secio "github.com/libp2p/go-libp2p-secio"
-	yamux "github.com/libp2p/go-libp2p-yamux"
-	tcp "github.com/libp2p/go-tcp-transport"
-	ws "github.com/libp2p/go-ws-transport"
-	"github.com/multiformats/go-multiaddr"
-)
-
-func main() {
-	ctx, cancel := context.WithCancel(context.Background())
-	defer cancel()
-
-	transports := libp2p.ChainOptions(
-		libp2p.Transport(tcp.NewTCPTransport),
-		libp2p.Transport(ws.New),
-	)
-
-	muxers := libp2p.ChainOptions(
-		libp2p.Muxer("/yamux/1.0.0", yamux.DefaultTransport),
-		libp2p.Muxer("/mplex/6.7.0", mplex.DefaultTransport),
-	)
-
-	security := libp2p.Security(secio.ID, secio.New)
-
-	listenAddrs := libp2p.ListenAddrStrings(
-		"/ip4/0.0.0.0/tcp/0",
-		"/ip4/0.0.0.0/tcp/0/ws",
-	)
-
-	host, err := libp2p.New(
-		ctx,
-		transports,
-		listenAddrs,
-		muxers,
-		security,
-	)
-	if err != nil {
-		panic(err)
-	}
-
-	// TODO: Register a stream handler for our protocol!
-
-	for _, addr := range host.Addrs() {
-		fmt.Println("Listening on", addr)
-	}
-
-	targetAddr, err := multiaddr.NewMultiaddr("/ip4/127.0.0.1/tcp/63785/p2p/QmWjz6xb8v9K4KnYEwP5Yk75k5mMBCehzWFLCvvQpYxF3d")
-	if err != nil {
-		panic(err)
-	}
-
-	targetInfo, err := peer.AddrInfoFromP2pAddr(targetAddr)
-	if err != nil {
-		panic(err)
-	}
-
-	err = host.Connect(ctx, *targetInfo)
-	if err != nil {
-		panic(err)
-	}
-
-	fmt.Println("Connected to", targetInfo.ID)
-
-	// TODO: Implement a simple read loop to read user input and send messages
-	// to peers we are connected to that support our protocol.
-
-	host.Close()
-}

examples/ipfs-camp-2019/04-Protocol/protocol.go

@@ -1,45 +0,0 @@
-package main
-
-import (
-	"bufio"
-	"fmt"
-	"io"
-	"os"
-
-	"github.com/libp2p/go-libp2p-core/network"
-)
-
-const protocol = "/libp2p/chat/1.0.0"
-
-func chatHandler(s network.Stream) {
-	var (
-		err   error
-		chunk []byte
-		line  string
-	)
-	r := bufio.NewReader(s)
-	for {
-		prefix := true
-		for prefix {
-			chunk, prefix, err = r.ReadLine()
-			switch err {
-			case io.EOF:
-				return
-			default:
-				fmt.Fprintln(os.Stderr, err)
-			}
-			line += string(chunk)
-		}
-		fmt.Println(line)
-		line = ""
-	}
-}
-
-func send(msg string, s network.Stream) error {
-	w := bufio.NewWriter(s)
-	n, err := w.WriteString(msg)
-	if n != len(msg) {
-		return fmt.Errorf("expected to write %d bytes, wrote %d", len(msg), n)
-	}
-	return err
-}