I'd like to install two four-foot tracks, one on each side of an exposed wooden support beam. I can't figure out where to put the junction box(es). I see track lighting on beams in photos, but I can't see where they put the box!

The lights I purchased have a standard track with the flat plate that goes over a recessed box. What if you can't recess the box? It's an industrial look- can I surface mount a metal junction box? If I do, how do I get the track up over the side of the box? If I put the box on the adjacent wall in the standard fashion, how do I get the track to make the right angle bend over to the box? Ugh. Do I have to put a big hole through the beam to inset a junction box to make this work?