The Spaniard is understood to have snubbed larger wages at West Bromwich Albion in order to sign a pre-contract agreement in south Wales, with his free transfer from Real Betis set to be formally ratified on July 1.
Canas told the Daily Mail: "The Premier League is the place where everyone wants to be now, and Swansea City is very attractive in the league due to the way they play, the manager they have and the friendly club that it is. I could not let this opportunity go to be honest.
"The manager was a quite important point. I had several options abroad and the fact that the manager knows you obviously helps when making the decision. His style of play is quite attractive and I do not think I will have any difficulties to fit in quickly.
"We had some options but Swansea was on top of them from the beginning - they showed strong interest and that was important to me."