feat(server): add websocket.

cmd/main.go

@@ -0,0 +1,11 @@
+package main
+
+import "github.com/dezh-tech/immortal/server"
+
+func main() {
+	s := server.NewServer()
+	err := s.Start()
+	if err != nil {
+		panic(err)
+	}
+}

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/mailru/easyjson v0.7.7
 	github.com/stretchr/testify v1.9.0
 	github.com/tidwall/gjson v1.17.3
+	golang.org/x/net v0.29.0
 )
 
 require (

go.sum

@@ -22,6 +22,8 @@ github.com/tidwall/match v1.1.1 h1:+Ho715JplO36QYgwN9PGYNhgZvoUSc9X2c80KVTi+GA=
 github.com/tidwall/match v1.1.1/go.mod h1:eRSPERbgtNPcGhD8UCthc6PmLEQXEWd3PRB5JTxsfmM=
 github.com/tidwall/pretty v1.2.0 h1:RWIZEg2iJ8/g6fDDYzMpobmaoGh5OLl4AXtGUGPcqCs=
 github.com/tidwall/pretty v1.2.0/go.mod h1:ITEVvHYasfjBbM0u2Pg8T2nJnzm8xPwvNhhsoaGGjNU=
+golang.org/x/net v0.29.0 h1:5ORfpBpCs4HzDYoodCDBbwHzdR5UrLBZ3sOnUJmFoHo=
+golang.org/x/net v0.29.0/go.mod h1:gLkgy8jTGERgjzMic6DS9+SP0ajcu6Xu3Orq/SpETg0=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

server/server.go

@@ -0,0 +1,63 @@
+package server
+
+import (
+	"errors"
+	"io"
+	"log"
+	"net/http"
+
+	// TODO::: replace with https://github.com/coder/websocket.
+	"github.com/dezh-tech/immortal/types/envelope"
+	"golang.org/x/net/websocket"
+)
+
+type Server struct {
+	conns map[*websocket.Conn]bool
+}
+
+func NewServer() *Server {
+	return &Server{
+		conns: make(map[*websocket.Conn]bool),
+	}
+}
+
+func (s *Server) Start() error {
+	http.Handle("/ws", websocket.Handler(s.handleWS))
+	err := http.ListenAndServe(":3000", nil) //nolint
+
+	return err
+}
+
+func (s *Server) handleWS(ws *websocket.Conn) {
+	// TODO::: replace with logger.
+	log.Printf("new connection: %s\n", ws.RemoteAddr())
+
+	// TODO::: make it concurrent safe.
+	s.conns[ws] = true
+
+	s.readLoop(ws)
+}
+
+func (s *Server) readLoop(ws *websocket.Conn) {
+	buf := make([]byte, 1024)
+	for {
+		n, err := ws.Read(buf)
+		if err != nil {
+			if errors.Is(err, io.EOF) {
+				break
+			}
+
+			// TODO::: replace with logger.
+			log.Printf("error in connection handling: %s\n", err)
+
+			// TODO::: drop connection?
+			continue
+		}
+
+		msg := buf[:n]
+		env := envelope.ParseMessage(msg)
+
+		// TODO::: replace with logger.
+		log.Printf("received envelope: %s\n", env.String())
+	}
+}

types/event/event.go

@@ -95,3 +95,12 @@ func (e *Event) IsValid() bool {
 	// TODO::: replace with libsecp256k1 (C++ version).
 	return sig.Verify(hash[:], pubkey)
 }
+
+func (e *Event) String() string {
+	ee, err := e.Encode()
+	if err != nil {
+		return ""
+	}
+
+	return string(ee)
+}

types/utils.go

@@ -24,7 +24,7 @@ func ContainsKind(target Kind, arr []Kind) bool {
 	return false
 }
 
-// Escaping strings for JSON encoding according to RFC8259.
+// EscapeString for JSON encoding according to RFC8259.
 // Also encloses result in quotation marks "".
 func EscapeString(dst []byte, s string) []byte {
 	dst = append(dst, '"')