Full-back Johnson, who has been an unused substitute recently after several weeks out with a knee injury, played 90 minutes in a behind-closed-doors practice match this week.
Cobblers boss Aidy Boothroyd told the media: "John is fit but he's still got some work to do behind the scenes.
"We want to get as many games in for him as we can but he might even be able to build up his match fitness by playing in the first team.
"I wouldn't say that we've missed him because Ben Tozer has been absolutely outstanding, but having Jonno back gives me different options."
Recent signing Roy O'Donovan made his debut as a half-time substitute during the 3-1 defeat at Rotherham last Saturday and the striker could be in line to make his home bow.
O'Donovan, like Johnson, played in the behind-closed-doors game at Stoke on Tuesday afternoon to build up his fitness.
Meanwhile, Boothroyd is keen to sign versatile defender Lee Collins, who has been training with the club, but a deal is unlikely to materialise before the weekend.
- Sports & Recreation
- Aidy Boothroyd