Follow the standard PSR-15

[PierrickVoulet]

Is your feature request related to a problem? Please describe.

This library defines and uses several middlewares without following the PSR-15 standard.

Describe the solution you'd like

Make it compliant to the standard PSR-15.

[hkdevandla]

Alice, lets assess on this in Q1 2022 to understand and what needs to be done to make the libraries compliant with PSR-15.