change_proxy.sh

#!/usr/bin/env bash

show_help() {
cat << EOF
Usage: ${0##*/} [-hegpsa] PROXYURL

Change Proxy for app and env. If PROXYURL parameter is not passed, the proxy is unset for that app or env.

    -h      Display help
    -e      Change env proxy variables
    -g      Change git proxy
    -p      Change package manager proxy
    -s      Change system proxy
    -a      Change proxy for all
EOF
}

change_env_proxy() {
if [ -z "$1" ]; then
    # Unset Env Vars
    echo unset http_proxy
    echo unset https_proxy
    echo unset ftp_proxy
    echo unset rsync_proxy
    echo unset no_proxy
    echo '# Use: eval $(!!);'
else
    # Set Env Vars
    echo export http_proxy="$1"
    echo export https_proxy="$1"
    echo export ftp_proxy="$1"
    echo export rsync_proxy="$1"
    echo export no_proxy="localhost,127.0.0.1"
    echo '# Use: eval $(!!);'
fi
}

change_git_proxy() {
if [ -z "$1" ]; then
    # Unset Git Proxy
    git config --global --unset http.proxy
    git config --global --unset https.proxy
else
    # Set Git Proxy
    git config --global http.proxy $1
    git config --global https.proxy $1
fi
}

change_pkg_mgr_proxy() {
if [ -z "$1" ]; then
    sudo rm /etc/apt/apt.conf.d/01proxy
else
    cmd="Acquire::http::Proxy \"$1\";"
    echo $cmd | sudo tee --append /etc/apt/apt.conf.d/01proxy > /dev/null
fi
}

change_sys_proxy() {
# Expects argument in the form:
# http://user:pwd@host:port

if [ -z "$1" ]; then
    gsettings set org.gnome.system.proxy mode 'none'
    exit 0
fi

url=$1

# Split with @ as separator
arr=(${url//@/ })

addr=${arr[1]}
# addr="host:port"
tmp=(${addr//:/ })

host=${tmp[0]}
port=${tmp[1]}

gsettings set org.gnome.system.proxy mode 'manual'
gsettings set org.gnome.system.proxy.http host $host
gsettings set org.gnome.system.proxy.http port $port
gsettings set org.gnome.system.proxy.https host $host
gsettings set org.gnome.system.proxy.https port $port
gsettings set org.gnome.system.proxy.ftp host $host
gsettings set org.gnome.system.proxy.ftp port $port
gsettings set org.gnome.system.proxy.socks host $host
gsettings set org.gnome.system.proxy.socks port $port
}


# Default all cases to 1
env_proxy=1
git_proxy=1
pkg_mgr_proxy=1
sys_proxy=1
all_proxy=1


OPTIND=1
while getopts "hegpsa" opt; do
    case "$opt" in
        # Show help
        h)  show_help
            exit 0
            ;;
        # Env Proxy
        e)  env_proxy=0
            ;;
        # Git Proxy
        g)  git_proxy=0
            ;;
        # Package Manager Proxy
        p)  pkg_mgr_proxy=0
            ;;
        # System Proxy
        s)  sys_proxy=0
            ;;
        # All
        a)  all_proxy=0
            ;;
        '?')
            show_help >&2
            exit 1
            ;;
    esac
done
shift "$((OPTIND-1))"


proxy_url="$*"

if [ $all_proxy -eq 0 ]; then
    change_env_proxy $proxy_url
    change_git_proxy $proxy_url
    change_sys_proxy $proxy_url
    change_pkg_mgr_proxy $proxy_url
elif [ $env_proxy -eq 0 ]; then
    change_env_proxy $proxy_url
elif [ $git_proxy -eq 0 ]; then
    change_git_proxy $proxy_url
elif [ $pkg_mgr_proxy -eq 0 ]; then
    change_pkg_mgr_proxy $proxy_url
elif [ $sys_proxy -eq 0 ]; then
    change_sys_proxy $proxy_url
fi