I ride a recumbent trike which makes me specially vulnerable, being so close to the ground and awkward to get up off, given the necessity of first setting the brakes and then heaving myself up and then lifting a long, awkward, heavy machine off the ground to put it between me and the dog. Also, they don't make jerseys for recumbent riders so I don't have any front pockets in which to carry pepper spray and my water bottle is not accessible from where I sit, since the front bottle holder has a GPS in it. I would have to hang a pouch around my neck to carry either spray or a gun. Yesterday, for the first time, a dog came at me. I stopped and yelled "no" and "get outta here" a couple of times, and that did the trick. But I recognize that if an abused pit bull came after me, that would be a life threatening situation. Fortunately, on my usual ride, the aforementioned was the only dog incident I've experienced. However, years ago when I rode a DF a dog came after me. I yelled to its owner who was sitting on his porch to get his dog and instead he urged the dog on. I stopped and walked the bike until I was far enough away and then I went to the state police to report him. Apparently, he and his relatives were known bad guys, but I was cautioned that he would learn my name if I brought charges. I decided it wasn't worth having my house burned down, so I never rode that route again.
My next door neighbor had a pack of unfenced dogs. Cyclists sped by downhill before the dogs could get started going after them and others avoided walking their dogs on that road. I decided to have it out, so I bought an electric cattle prod and walked my dog past the house. The dogs came out and surrounded me and my dog and my dog wrapped the leash around my legs and things were getting hairy when the owner came out and got them away. At that point I notified the local animal control officer and he said I'd need photographic proof that her dogs were off her property and not leashed. I managed to get that photo at another time and they were due in court with a large fine. I offered a deal. If they would put up a fence, I'd drop the charges. One day before the court appearance she and a bunch of her redneck friends built a fenced enclosure and that was the end of that.