Implement basic ws server and client

ws-client/go.mod

@@ -0,0 +1,5 @@
+module main
+
+go 1.22.4
+
+require github.com/gorilla/websocket v1.5.3

ws-client/go.sum

@@ -0,0 +1,2 @@
+github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
+github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=

ws-client/main.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"log"
+	"time"
+
+	"github.com/gorilla/websocket"
+)
+
+type WSConnection struct {
+	url     string
+	conn    *websocket.Conn
+	errChan chan error
+}
+
+func (ws *WSConnection) readMessage() {
+	log.Printf("Reading messages")
+	for {
+		_, message, err := ws.conn.ReadMessage()
+		if err != nil {
+			ws.errChan <- err
+			return
+		}
+		log.Printf("Received: %s", message)
+	}
+}
+
+func (ws *WSConnection) writeMessage(message string) {
+	err := ws.conn.WriteMessage(websocket.TextMessage, []byte(message))
+	if err != nil {
+		log.Printf("Error during message writing: %v", err)
+		ws.errChan <- err
+		return
+	}
+}
+
+func (ws *WSConnection) handleError() {
+	for {
+		err := <-ws.errChan
+		log.Println("Error during message reading:", err)
+
+		time.Sleep(5 * time.Second)
+		ws.open()
+	}
+}
+
+func (ws *WSConnection) open() {
+	log.Printf("Connecting to %s", ws.url)
+	conn, _, err := websocket.DefaultDialer.Dial(ws.url, nil)
+	if err != nil {
+		log.Println("Error during connection:", err)
+		ws.errChan <- err
+		return
+	}
+	log.Printf("Connected")
+	ws.conn = conn
+	ws.errChan = make(chan error)
+	go ws.readMessage()
+	go ws.handleError()
+}
+
+func main() {
+	log.SetFlags(log.Lmicroseconds)
+
+	wsConn := WSConnection{
+		url: "ws://localhost:8080/ws",
+	}
+	wsConn.open()
+
+	ticker := time.NewTicker(time.Second)
+	defer ticker.Stop()
+
+	for timestamp := range ticker.C {
+		wsConn.writeMessage(timestamp.String())
+	}
+}

ws-server/main.go

@@ -2,10 +2,48 @@ package main
 
 import (
 	"fmt"
+	"log"
+	"net/http"
 
 	"github.com/gorilla/websocket"
 )
 
+var upgrader = websocket.Upgrader{}
+
+// upgrader.CheckOrigin = func(r *http.Request) bool { return true }
+
+func wsHandler(responseWriter http.ResponseWriter, request *http.Request) {
+	conn, err := upgrader.Upgrade(responseWriter, request, nil)
+	if err != nil {
+		fmt.Println("Error during connection upgrade:", err)
+		return
+	}
+	defer conn.Close()
+
+	for {
+		messageType, packet, err := conn.ReadMessage()
+
+		if err != nil {
+			fmt.Println("Error during message reading:", err)
+			break
+		}
+		log.Printf("Received: %v %s", messageType, packet)
+
+		// err = conn.WriteMessage(messageType, packet)
+		// if err != nil {
+		// 	fmt.Println("Error during message writing:", err)
+		// 	break
+		// }
+	}
+}
+
 func main() {
-	fmt.Println("Hello, World!")
+	log.SetFlags(log.Lmicroseconds)
-}
+
+	http.HandleFunc("/ws", wsHandler)
+	log.Println("Server starting on :8080")
+	err := http.ListenAndServe(":8080", nil)
+	if err != nil {
+		log.Println("Error starting server:", err)
+	}
+}