I had a dog attack while my son and I while we were walking our Basset Hound. You really need to report the incident to the police. While they can not do anything unless the dog breaks skin, the report needs to be made. In my case, the Colleyville PD and Animal Control paid a visit to the neighbor, informed him of the consequences of what would happen to him and his dog if the dog drew blood. He has not let his dog off a leash since. Sometimes a visit by a person in uniform is all they need to start acting like responsible pet owners.
Sadly, I'm now carrying pepper spray with me even if it's just walking my dog in my own neighborhood.