npm install not workjing behind proxy

C++
npm config set strict-ssl false

# Set npm to use http instead of https
npm config set registry "http://registry.npmjs.org/"

# install your package with below syntax, can leave out the
# username:password section if your proxy does not require
# you to authenticate. The "http://" part is very important
npm --proxy http://username:[email protected]:80 install packagename
Source

Also in C++: