Proxy switchy script

proxy_switch.sh

#!/bin/sh

if [[ -z "$1" ]]; then
  echo "Usage: proxy_switch.sh en 1.1.1.1:8080.
               proxy_switch.sh dis"
  exit 2;
fi

if [[ "$1" == "en" ]]; then
  export http_proxy=http://$2
  export https_proxy=http://$2
  export HTTP_PROXY=http://$2
  export HTTPS_PROXY=http://$2
  git config --global http.proxy $2
  npm config set proxy http://$2
  npm config set https-proxy http://$2
elif [[ "$1" == "dis" ]]; then
  export http_proxy=
  export https_proxy=
  export HTTP_PROXY=
  export HTTPS_PROXY=
  git config --global http.proxy ""
  npm config delete proxy
  npm config delete https-proxy
fi

Unusually, in my case (I'm using zsh btw) setting the variables to empty doesn't work though, so we maybe need something else.