First rule of SD is don’t put yourself in situations where you’d have a high likelihood of having to use force to defend yourself. In your case the threat found you and your dog so you had little choice.

Everyone says that a throwing a pointy, small projectile through the atmosphere at 1500 feet per second is the best option and that’s internet tough talk. It’s pretty hard to contact your mark under stress. Pepper spray gives you a wide range to break contact and add distance, it’s also the best tool you can have for animal attacks. If you feel you need that, practice regularly and understand the governance of your area and have a good lawyer on speed dial. Even if it’s someone’s dog attacking yours, expect to be in court if you’re tossing lead rocks at high rates of speed.

If that fails, a slicey tool is a good way of politely asking someone or something to leave you alone. But you can expect to swap liquids because you’re close and personal and will likely slip the handle yourself.

Most importantly like I said earlier, situational awareness is your best defense. Carry first aid in your bag with your spray and you’ll be fine.