ceremonyclient/go-libp2p/examples/multipro/ping.go
2023-08-20 23:07:43 -05:00

162 lines
4.1 KiB
Go

package main
import (
"fmt"
"io"
"log"
"sync"
"github.com/libp2p/go-libp2p/core/host"
"github.com/libp2p/go-libp2p/core/network"
proto "github.com/gogo/protobuf/proto"
uuid "github.com/google/uuid"
p2p "github.com/libp2p/go-libp2p/examples/multipro/pb"
)
// pattern: /protocol-name/request-or-response-message/version
const pingRequest = "/ping/pingreq/0.0.1"
const pingResponse = "/ping/pingresp/0.0.1"
// PingProtocol type
type PingProtocol struct {
node *Node // local host
mu sync.Mutex
requests map[string]*p2p.PingRequest // used to access request data from response handlers. Protected by mu
done chan bool // only for demo purposes to stop main from terminating
}
func NewPingProtocol(node *Node, done chan bool) *PingProtocol {
p := &PingProtocol{node: node, requests: make(map[string]*p2p.PingRequest), done: done}
node.SetStreamHandler(pingRequest, p.onPingRequest)
node.SetStreamHandler(pingResponse, p.onPingResponse)
return p
}
// remote peer requests handler
func (p *PingProtocol) onPingRequest(s network.Stream) {
// get request data
data := &p2p.PingRequest{}
buf, err := io.ReadAll(s)
if err != nil {
s.Reset()
log.Println(err)
return
}
s.Close()
// unmarshal it
err = proto.Unmarshal(buf, data)
if err != nil {
log.Println(err)
return
}
log.Printf("%s: Received ping request from %s. Message: %s", s.Conn().LocalPeer(), s.Conn().RemotePeer(), data.Message)
valid := p.node.authenticateMessage(data, data.MessageData)
if !valid {
log.Println("Failed to authenticate message")
return
}
// generate response message
log.Printf("%s: Sending ping response to %s. Message id: %s...", s.Conn().LocalPeer(), s.Conn().RemotePeer(), data.MessageData.Id)
resp := &p2p.PingResponse{MessageData: p.node.NewMessageData(data.MessageData.Id, false),
Message: fmt.Sprintf("Ping response from %s", p.node.ID())}
// sign the data
signature, err := p.node.signProtoMessage(resp)
if err != nil {
log.Println("failed to sign response")
return
}
// add the signature to the message
resp.MessageData.Sign = signature
// send the response
ok := p.node.sendProtoMessage(s.Conn().RemotePeer(), pingResponse, resp)
if ok {
log.Printf("%s: Ping response to %s sent.", s.Conn().LocalPeer().String(), s.Conn().RemotePeer().String())
}
p.done <- true
}
// remote ping response handler
func (p *PingProtocol) onPingResponse(s network.Stream) {
data := &p2p.PingResponse{}
buf, err := io.ReadAll(s)
if err != nil {
s.Reset()
log.Println(err)
return
}
s.Close()
// unmarshal it
err = proto.Unmarshal(buf, data)
if err != nil {
log.Println(err)
return
}
valid := p.node.authenticateMessage(data, data.MessageData)
if !valid {
log.Println("Failed to authenticate message")
return
}
// locate request data and remove it if found
p.mu.Lock()
_, ok := p.requests[data.MessageData.Id]
if ok {
// remove request from map as we have processed it here
delete(p.requests, data.MessageData.Id)
} else {
log.Println("Failed to locate request data boject for response")
p.mu.Unlock()
return
}
p.mu.Unlock()
log.Printf("%s: Received ping response from %s. Message id:%s. Message: %s.", s.Conn().LocalPeer(), s.Conn().RemotePeer(), data.MessageData.Id, data.Message)
p.done <- true
}
func (p *PingProtocol) Ping(host host.Host) bool {
log.Printf("%s: Sending ping to: %s....", p.node.ID(), host.ID())
// create message data
req := &p2p.PingRequest{MessageData: p.node.NewMessageData(uuid.New().String(), false),
Message: fmt.Sprintf("Ping from %s", p.node.ID())}
// sign the data
signature, err := p.node.signProtoMessage(req)
if err != nil {
log.Println("failed to sign pb data")
return false
}
// add the signature to the message
req.MessageData.Sign = signature
// store ref request so response handler has access to it
p.mu.Lock()
p.requests[req.MessageData.Id] = req
p.mu.Unlock()
ok := p.node.sendProtoMessage(host.ID(), pingRequest, req)
if !ok {
return false
}
log.Printf("%s: Ping to: %s was sent. Message Id: %s, Message: %s", p.node.ID(), host.ID(), req.MessageData.Id, req.Message)
return true
}