inviting ex's friend to dinner?

Ok so one of my friends has been hanging out with my ex's friends(from their group).I met the guy for like 10 minutes but them two chatted the most and he said how it was nice meeting me after all the things he has heard after the break up(everyone said something on both sides-my and his).So since my friend and him went and played pool,hung out another time and then went swimming together I thought that they could join me and this guy Cody(he already asked me out for next week and I said yes).I am not trying to start a war but if my friends likes the guy and vice versa that does not mean that idk it will cause drama or so I hope not.

Is this a bad idea?I last spoke with my ex on Sunday(easter) and we are supposed to be "friends" or whatever.Tomorrow here is the catch:the guy that I am going on a date with he is taking me to the bar where my ex and his friends will be there.I am not going in to stir more trouble but rather outside so the guy brings me my drink and we talk. I am not sure how things will work out but does anyone think that this will get messy?