Both players look set to put pen to paper this week as the Rocks management start to assemble their squad ahead of the new Isthmian Premier Division campaign which kicks off in August.
And former Burnley striker Blake says the news is "massive" for the club. He added: "Amadou is a stabilising influence for us and has been brilliant since he arrived. He gives the team great confidence and what is also admirable is the fact that he is so demanding of his team-mates which means they work harder and are always ready to improve their standards.
"As for Harvey, everyone knows what we think of him here at this football club, not only as a player but as a man. He is a great character, has great qualities and always striving to improve and that bodes well for us.
"To sign these two is massive for us and just the start. It means we can have every faith that we can anticipate a good season when we eventually kick off once more.”
Tangara, from the Ivory Coast and formerly with Kingstonian, Cheshunt, Merstham and Dulwich Hamlet, has been a rock-steady custodian during his two-year spell with the club.
Versatile Whyte played for the club during two loan spells from Havant & Waterlooville before signing permanently in 2016. Since then he has gone on to become a fans' favourite and a natural leader.
Both players are seen as hugely influential both on and off the pitch and their commitment to the Nye Camp outfit is being viewed as a huge boost. The news comes after the Rocks snared technically-gifted defender Joe Hancott after he left League One Portsmouth.
Club bosses say the new deals are just the start of their recruitment as they prepare to ready their squad to go again following the disappointment of the second premature conclusion to the action through the pandemic.
General managing Simon Cook said: "Both Jack and Robbie are working hard behind the scenes talking to players and we are making great progress. Harvey and Amadou are big players for us and we're delighted they are about to sign new contracts. Hopefully it's the start of more good news in regards to retaining players and recruiting as well."