Scotland international Swinson has been out of action with a hand injury since November, Johnson suffered a broken jaw in the game against Montpellier in December and Cummings has been out since the beginning of the year.
Glasgow Warriors Head Coach Dave Rennie said: "Although we were disappointed to only get a draw against the Dragons we played the game in the right areas of the field and showed good attacking intent.
"The Cheetahs are a good side across the park and we know we're going to have to be more clinical with our possession this Friday to get the result.
"Sam, Scott and Tim are all influentual players for us so to have them back is a huge boost."
Not available due to injury: Brian Alainu'uese (knee), Fraser Brown (head), Alex Dunbar (thigh), Zander Fagerson (foot), Callum Gibbins (achilles), Rory Hughes (shoulder), Pat MacArthur (shoulder), Leonardo Sarto (shoulder) and George Turner (knee).
Not available due to international commitments: Jamie Bhatti (Scotland), Jonny Gray (Scotland), Stuart Hogg (Scotland), Peter Horne (Scotland), Huw Jones (Scotland) Ali Price (Scotland), Finn Russell (Scotland), Tommy Seymour (Scotland) and Ryan Wilson (Scotland).