Function WaitForTCPPort

utils/ssh.go:753–799

(ctx context.Context, host string, port int, overallTimeout time.Duration)

}

func WaitForTCPPort(ctx context.Context, host string, port int, overallTimeout time.Duration) error {
	address := net.JoinHostPort(host, strconv.Itoa(port))
	deadline := time.Now().Add(overallTimeout)
	backoff := 1 * time.Second
	maxBackoff := 10 * time.Second
	attempt := 0

	for {
		attempt++
		if err := ctx.Err(); err != nil {
			return fmt.Errorf("%w: TCP port check cancelled: %w", ErrSSHUnreachable, err)
		}
		if time.Now().After(deadline) {
			return fmt.Errorf("%w: TCP port %s not available after %v", ErrSSHUnreachable, address, overallTimeout)
		}

		remaining := time.Until(deadline)
		attemptTimeout := remaining
		if attemptTimeout > 5*time.Second {
			attemptTimeout = 5 * time.Second
		}
		if attemptTimeout <= 0 {
			return fmt.Errorf("%w: TCP port %s not available after %v", ErrSSHUnreachable, address, overallTimeout)
		}

		dialer := &net.Dialer{
			Timeout: attemptTimeout,
		}

		conn, err := dialer.DialContext(ctx, "tcp", address)
		if err == nil {
			conn.Close()
			return nil
		}

		// Only retry on connection-related errors
		if !shouldRetryDial(err) {
			return fmt.Errorf("%w: TCP port check failed: %w", ErrSSHUnreachable, err)
		}

		// Exponential backoff with cap
		if err := sleepWithContext(ctx, backoff); err != nil {
			return fmt.Errorf("%w: TCP port check cancelled: %w", ErrSSHUnreachable, err)
		}
		backoff = minDuration(backoff*2, maxBackoff)
	}
}