set_github_ssh_key.sh

#!/bin/sh

#get GitHub user name if it is not provided
if [ $# -lt 1 ]; then
	echo -n "Enter GitHub user name: "
	read _githubUsername 
else
	_githubUsername=$1
fi

#get GitHub password
echo -n "Enter GitHub password: "
read -s _githubPassword
echo

#get SSH password
echo -n "Enter SSH Key password: "
read -s _sshKeyPassword
echo

#get GitHub SSH title
echo "Enter GitHub SSH Title [hostname -s]: " 
read _githubSSHKeyTitle
_githubSSHKeyTitle=${_githubSSHKeyTitle:`hostname -s`}

#github settings
_githubAuthURL="https://api.github.com/authorizations"
_githubUserKeyURL="https://api.github.com/user/keys"

#ssh key settings
_sshKeyDir="$HOME/.ssh"
_sshKeyFile="$_sshKeyDir/id_rsa"
_sshKeyPubFile=$_sshKeyFile".pub"

#create ssh folder if it does not exist
if [ ! -e $_sshKeyDir ]; then
	mkdir -p $_sshKeyDir
fi

#run ssh-keygen if private key file does not exist
if [ ! -e $_sshKeyFile ]; then
	ssh-keygen -f $_sshKeyFile -N "$_sshKeyPassword"
fi

#generate a token
_token=`curl -u "${_githubUsername}:${_githubPassword}" -d "{\"scopes\":[\"user\"]}" $_githubAuthURL | grep "token" | cut -d"\"" -f4`

#post ssh public key
curl -H "Authorization: token $_token" $_githubUserKeyURL -d "{ \"title\":\"$_githubSSHKeyTitle\", \"key\":\"`cat $_sshKeyPubFile`\" }"

exit 0