Add SSH public key

add_public_key.sh

#!/bin/bash
# Usage: 
# First, source this script:
# $ source add_public_key.sh
# Then, use the function add user:
# $ add_public_key john 'ssh-rsa very-long-hash'


add_public_key()
{
    local username="$1"
    local ssh_key="$2"
    local ssh_dir=$(eval echo ~$username/.ssh)
    local auth_key_file="$ssh_dir/authorized_keys"
    mkdir "$ssh_dir"
    echo "$ssh_key" > "$auth_key_file"
    chown -R "$username:$username" "$ssh_dir"
    chmod 700 "$ssh_dir"
    chmod 600 "$auth_key_file"
}