add netbird embed experiment

experiment/netbird-load/main.go

@@ -0,0 +1,134 @@
+// netbird-load launches N userspace NetBird nodes and has each one periodically
+// TCP-dial a peer to measure connect latency through the wireguard overlay.
+//
+// Usage:
+//
+//	NB_SETUP_KEY=nb-... go run . -count 10 -interval 5s -target 100.x.y.z:22
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"math/rand/v2"
+	"os"
+	"os/signal"
+	"path/filepath"
+	"sync"
+	"syscall"
+	"time"
+
+	"github.com/netbirdio/netbird/client/embed"
+)
+
+func main() {
+	setupKey := flag.String("setupkey", os.Getenv("NB_SETUP_KEY"),
+		"NetBird reusable setup key (or set NB_SETUP_KEY).")
+	mgmt := flag.String("mgmt", os.Getenv("NB_MGMT_URL"),
+		"NetBird management URL (empty = embed default, i.e. NetBird Cloud).")
+	count := flag.Int("count", 10, "Number of embedded netbird nodes to launch.")
+	interval := flag.Duration("interval", 5*time.Second, "Interval between actions per node.")
+	hostnamePrefix := flag.String("hostname-prefix", "uncloud", "Hostname prefix for netbird nodes.")
+	stateRoot := flag.String("state-dir", "./state", "Directory to keep netbird state (empty = a fresh temp dir).")
+	target := flag.String("target", "", "TCP host:port to dial each tick (required).")
+	flag.Parse()
+
+	if *setupKey == "" {
+		log.Fatal("missing NetBird setup key: pass -setupkey or set NB_SETUP_KEY.")
+	}
+	if *target == "" {
+		log.Fatal("missing -target: provide a TCP host:port reachable through the netbird network.")
+	}
+
+	root := *stateRoot
+	if root == "" {
+		var err error
+		root, err = os.MkdirTemp("", "netbird-load-*")
+		if err != nil {
+			log.Fatalf("mktemp: %v", err)
+		}
+		defer os.RemoveAll(root)
+	} else if err := os.MkdirAll(root, 0o700); err != nil {
+		log.Fatalf("mkdir state dir: %v", err)
+	}
+
+	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
+	defer stop()
+
+	var wg sync.WaitGroup
+	for i := 0; i < *count; i++ {
+		wg.Add(1)
+		go func(id int) {
+			defer wg.Done()
+			runNode(ctx, id, *setupKey, *mgmt, *hostnamePrefix, root, *target, *interval)
+		}(i)
+	}
+	wg.Wait()
+}
+
+func runNode(ctx context.Context, id int, setupKey, mgmt, prefix, stateRoot, target string, interval time.Duration) {
+	logPrefix := fmt.Sprintf("[node-%02d] ", id)
+	logger := log.New(os.Stderr, logPrefix, log.LstdFlags|log.Lmsgprefix)
+
+	nodeDir := filepath.Join(stateRoot, fmt.Sprintf("node-%02d", id))
+	deviceName := fmt.Sprintf("%s-%02d", prefix, id)
+
+	client, err := embed.New(embed.Options{
+		DeviceName:    deviceName,
+		SetupKey:      setupKey,
+		ManagementURL: mgmt,
+		StatePath:     nodeDir,
+		ConfigPath:    filepath.Join(nodeDir, "config"),
+		// Silence per-node netbird chatter. Swap to os.Stderr to debug.
+		LogOutput: io.Discard,
+		//NoUserspace: true,
+	})
+	if err != nil {
+		logger.Printf("netbird new: %v", err)
+		return
+	}
+	defer func() {
+		stopCtx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+		_ = client.Stop(stopCtx)
+	}()
+
+	upCtx, cancel := context.WithTimeout(ctx, 60*time.Second)
+	defer cancel()
+	if err := client.Start(upCtx); err != nil {
+		logger.Printf("netbird start: %v", err)
+		return
+	}
+	logger.Printf("up as %s", deviceName)
+
+	// Stagger ticks so all nodes don't fire in lockstep.
+	time.Sleep(time.Duration(rand.Int64N(int64(interval))))
+
+	tick := time.NewTicker(interval)
+	defer tick.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-tick.C:
+			doDial(ctx, client, target, logger)
+		}
+	}
+}
+
+func doDial(ctx context.Context, c *embed.Client, target string, logger *log.Logger) {
+	dctx, cancel := context.WithTimeout(ctx, 5*time.Second)
+	defer cancel()
+
+	start := time.Now()
+	conn, err := c.Dial(dctx, "tcp", target)
+	if err != nil {
+		logger.Printf("dial %s: %v", target, err)
+		return
+	}
+	latency := time.Since(start)
+	_ = conn.Close()
+	logger.Printf("dial %s ok in %.1fms", target, float64(latency.Microseconds())/1000)
+}