replace github.com/eosswedenorg-go/tcp_server with github.com/panjf2000/gnet

internal/server/server.go

@@ -1,64 +1,111 @@
 package server
 
 import (
+	"context"
+	"fmt"
 	"strings"
+	"time"
 
 	"github.com/eosswedenorg-go/haproxy/agentcheck"
-	"github.com/eosswedenorg-go/tcp_server"
 	"github.com/eosswedenorg/antelope-api-healthcheck/internal/api"
 	log "github.com/inconshreveable/log15"
+	"github.com/panjf2000/gnet/v2"
 )
 
-//  onTcpMessage callback function
-// ---------------------------------------------------------
+type Server struct {
+	gnet.BuiltinEventEngine
 
-func onTcpMessage(c *tcp_server.Client, args string) {
+	addr string
+	eng  gnet.Engine
+}
+
+func New(addr string) *Server {
+	return &Server{
+		addr: fmt.Sprintf("tcp://%s", addr),
+	}
+}
+
+//	OnBoot callback function
+//
+// ---------------------------------------------------------
+func (s *Server) OnBoot(eng gnet.Engine) gnet.Action {
+	s.eng = eng
+	log.Info("Server started", "addr", s.addr)
+	return gnet.None
+}
+
+//	OnShutdown callback function
+//
+// ---------------------------------------------------------
+func (s *Server) OnShutdown(eng gnet.Engine) {
+	log.Info("Server shutdown")
+}
+
+//	OnTick callback function
+//
+// ---------------------------------------------------------
+func (s *Server) OnTick() (time.Duration, gnet.Action) {
+	log.Info("Server info", "connections", s.eng.CountConnections())
+	return time.Second * 10, gnet.None
+}
+
+//	OnTraffic callback function
+//
+// ---------------------------------------------------------
+func (s *Server) OnTraffic(c gnet.Conn) gnet.Action {
 	logger := log.Root()
 
+	req, err := c.Next(-1)
+	if err != nil {
+		logger.Error("Read", "message", err)
+		return gnet.Close
+	}
+
 	// Check api.
 	// -------------------
-	healthCheckApi, err := ParseRequest(args)
+	healthCheckApi, err := ParseRequest(string(req))
 	if err != nil {
 		logger.Warn("Agent request error", "message", err)
 		resp := agentcheck.NewStatusMessageResponse(agentcheck.Fail, "")
 
-		_, err = c.WriteString(resp.String())
+		_, err = c.Write([]byte(resp.String()))
 		if err != nil {
-			logger.Error("WriteString", "message", err)
+			logger.Error("Write", "message", err)
 		}
 
-		c.Close()
-		return
+		return gnet.Close
 	}
 
-	status, msg := healthCheckApi.Call()
+	// gnet library does not like blocking calls.
+	// as we do a blocking http call here, we need to wrap it in a goroutine.
+	go func() {
+		status, msg := healthCheckApi.Call()
 
-	params := api.LogParams{}
-	params.Add("status", strings.TrimSpace(status.String()))
+		params := api.LogParams{}
+		params.Add("status", strings.TrimSpace(status.String()))
 
-	if msg != "OK" && len(msg) > 0 {
-		params.Add("error", msg)
-	}
+		if msg != "OK" && len(msg) > 0 {
+			params.Add("error", msg)
+		}
 
-	logger.Info("API Check", params.Combine(healthCheckApi.LogInfo())...)
-	// Report status to HAproxy
-	_, err = c.WriteString(status.String())
-	if err != nil {
-		logger.Error("WriteString", "message", err)
-	}
-	c.Close()
+		logger.Info("API Check", params.Combine(healthCheckApi.LogInfo())...)
+		// Report status to HAproxy
+		err = c.AsyncWrite([]byte(status.String()), nil)
+		if err != nil {
+			logger.Error("Write", "message", err)
+		}
+	}()
+
+	return gnet.None
 }
 
-//  Start
+func (s *Server) Close() error {
+	return s.eng.Stop(context.Background())
+}
+
+//	Run the server event loop.
+//
 // ---------------------------------------------------------
-
-func Start(addr string) (*tcp_server.Server, error) {
-	server := tcp_server.New(addr)
-	server.OnMessage(onTcpMessage)
-
-	err := server.Connect()
-	if err == nil {
-		err = server.Listen()
-	}
-	return server, err
+func (s *Server) Run() error {
+	return gnet.Run(s, s.addr, gnet.WithMulticore(true), gnet.WithTicker(true))
 }