read from env var Q3RCON_STALE_SESSION_TIMEOUT

add a trace level log when a session gets deleted.

cmd/q3rcon-proxy/main.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"slices"
 	"strings"
+	"time"
 
 	log "github.com/sirupsen/logrus"
 
@@ -30,20 +31,28 @@ func main() {
 		host = "0.0.0.0"
 	}
 
+	staleTimeout, err := getEnvInt("Q3RCON_STALE_SESSION_TIMEOUT")
+	if err != nil {
+		log.Fatalf("unable to parse Q3RCON_STALE_SESSION_TIMEOUT: %s", err.Error())
+	}
+
 	for _, proxy := range strings.Split(proxies, ";") {
-		go start(host, proxy)
+		go start(host, proxy, staleTimeout)
 	}
 
 	<-make(chan int)
 }
 
-func start(host, proxy string) {
+func start(host, proxy string, staleTimeout int) {
 	port, target := func() (string, string) {
 		x := strings.Split(proxy, ":")
 		return x[0], x[1]
 	}()
 
-	c, err := udpproxy.New(fmt.Sprintf("%s:%s", host, port), fmt.Sprintf("127.0.0.1:%s", target))
+	c, err := udpproxy.New(
+		fmt.Sprintf("%s:%s", host, port),
+		fmt.Sprintf("127.0.0.1:%s", target),
+		udpproxy.WithStaleTimeout(time.Duration(staleTimeout)*time.Minute))
 	if err != nil {
 		log.Fatal(err)
 	}

pkg/udpproxy/udpproxy.go

@@ -8,6 +8,21 @@ import (
 	log "github.com/sirupsen/logrus"
 )
 
+// Option is a functional option type that allows us to configure the Client.
+type Option func(*Client)
+
+// WithStaleTimeout is a functional option to set the stale session timeout
+func WithStaleTimeout(timeout time.Duration) Option {
+	return func(c *Client) {
+		if timeout < time.Minute {
+			log.Warnf("cannot set stale session timeout to less than 1 minute.. defaulting to 5 minutes")
+			return
+		}
+
+		c.timeout = timeout
+	}
+}
+
 type Client struct {
 	laddr *net.UDPAddr
 	raddr *net.UDPAddr
@@ -16,9 +31,11 @@ type Client struct {
 
 	mutex    sync.RWMutex
 	sessions map[string]*session
+
+	timeout time.Duration
 }
 
-func New(port, target string) (*Client, error) {
+func New(port, target string, options ...Option) (*Client, error) {
 	laddr, err := net.ResolveUDPAddr("udp", port)
 	if err != nil {
 		return nil, err
@@ -29,12 +46,19 @@ func New(port, target string) (*Client, error) {
 		return nil, err
 	}
 
-	return &Client{
+	c := &Client{
 		laddr:    laddr,
 		raddr:    raddr,
 		mutex:    sync.RWMutex{},
 		sessions: map[string]*session{},
-	}, nil
+		timeout:  5 * time.Minute,
+	}
+
+	for _, o := range options {
+		o(c)
+	}
+
+	return c, nil
 }
 
 func (c *Client) ListenAndServe() error {
@@ -76,8 +100,9 @@ func (c *Client) pruneSessions() {
 	for range ticker.C {
 		for _, session := range c.sessions {
 			c.mutex.RLock()
-			if time.Since(session.updateTime) > time.Minute*5 {
+			if time.Since(session.updateTime) > c.timeout {
 				delete(c.sessions, session.caddr.String())
+				log.Tracef("session for %s deleted", session.caddr)
 			}
 			c.mutex.RUnlock()
 		}