Add tailscale helpers (#1604)

pkg/tailscale/utils.go

@@ -0,0 +1,49 @@
+package tailscale
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+)
+
+const LoftTSNetDomain = "ts.loft"
+
+func GetHostname() (string, error) {
+	osHostname, err := os.Hostname()
+	if err != nil {
+		fmt.Printf("Failed to get hostname: %v\n", err)
+		return "", err
+	}
+	osHostname = strings.ToLower(strings.ReplaceAll(osHostname, ".", "-"))
+	return fmt.Sprintf("devpod.%v.client", osHostname), nil
+}
+
+func GetURL(host string, port int) string {
+	if port == 0 {
+		return fmt.Sprintf("%s.%s", host, LoftTSNetDomain)
+	}
+	return fmt.Sprintf("%s.%s:%d", host, LoftTSNetDomain, port)
+}
+
+func DirectTunnel(ctx context.Context, network TSNet, host string, port int, stdin io.Reader, stdout io.Writer) error {
+	address := fmt.Sprintf("%s.%s:%d", host, LoftTSNetDomain, port)
+	conn, err := network.Dial(ctx, "tcp", address)
+	if err != nil {
+		return fmt.Errorf("failed to connect to SSH server in proxy mode: %w", err)
+	}
+	defer conn.Close()
+
+	// Forward stdin, stdout, and stderr for proxy mode
+	go func() {
+		_, _ = io.Copy(conn, stdin)
+	}()
+	go func() {
+		_, _ = io.Copy(stdout, conn)
+	}()
+
+	// Block until the connection is closed
+	<-ctx.Done()
+	return nil
+}