Knicks All-Star Julius Randle won’t be testing free agency in 2022.

A source confirmed he has agreed to a four-year, $117 million extension. Randle said earlier this season he wanted to retire as a Knick.

According to a source close to Randle, the power forward loves the passion of the New York fans. Also, Randle wanted to sign early to give the club as much flexibility as possible next summer.

Randle’s agency is Creative Artists Agency, which Knicks president Leon Rose used to run. And that’s no small matter in CAA making this long-term commitment happen without any drama.

This, too, will end any speculation the Knicks aren’t building around Randle, whom former president Steve Mills signed as a fallback in 2019 after missing out on Kevin Durant.

Randle could’ve made more on the open market and gained a maximum contract in the $200 million range if he duplicated this past season, when he played 71 of 72 games and led the Knicks to their first playoff berth in eight years.

The extension doesn’t help the Knicks in 2022, however. The Knicks could have gone over the cap in 2022 to re-sign him. The lower number, though, will give them relief in 2023 and 2024.

The Knicks likely won’t have cap space now in 2022 unless they unload contracts, and the club feels they’ve re-signed players to two-year guaranteed deals who are moveable in Nerlens Noel, Derrick Rose and Alec Burks.

The Knicks realize cap space isn’t the end all and be all in acquiring stars. Just ask Miami, which made a sign-and-trade to reel in top Knicks point guard target Kyle Lowry.

Entering last season, Randle was viewed as a trade chip. In November, Leon Rose drafted power forward Obi Toppin in the rescheduled lottery and made big offers to free-agent forward Christian Wood, Jerami Grant and “stretch 4’’ Danilo Gallinari.

After a vigorous pandemic-extended offseason of training in Dallas, Randle came back with a vengeance after a disappointing first year in New York.

Randle earned the NBA’s Most Improved Player Award but then flopped in the playoffs against Atlanta (shooting 29.8 percent from the field). A source recently told The Post he was seriously debating whether to take the unrestricted route or sign on.

Perhaps the Knicks’ signings of Kemba Walker — even if he’s aging and injury-plagued — and Evan Fournier swayed him. The two players will make it easier for Randle to operate on the offensive end after Atlanta bottled him up in the playoffs.

In playing a point forward role, Randle averaged 24.1 points, 10.2 rebounds and 6.0 assists in the regular season and shot a massively improved 41.1 percent from 3-point land. He still must prove he can recruit a superstar player to the roster next offseason. Lowry’s decision to go to Miami was to play with Jimmy Butler.

Randle is known as a family man, who married young and is expecting his second child, and isn’t known to be part of any player clique.

In a midseason essay for the Players’ Tribune, Randle wrote about his happiness in remaining in New York long term.

“More than any team I’ve ever been on, with this year’s Knicks, it feels like we have a collective purpose,” Randle wrote in the piece. “And I think that’s also one of the things that Thibs [Tom Thibodeau] has been great at bringing to the table.

“This idea of how we can have our goals as individuals, and then our goals as a team and if we have the right mindset, there’s no reason those goals can’t feed into each other. It just feels like something good is happening.”

Thibodeau raved all season about Randle’s leadership, calling him “the engine’’ and referenced how in shape he was right from the first OTA for the “Delete 8’’ back in September. Randle is spending the offseason in his hometown of Dallas.

Even former Knick and current franchise agitator Charles Oakley couldn’t help himself recently. “I think [Randle] is a better version of Zion Williamson,’’ Oakley said.