Bash script to SSH into the Google Cloud shell instance in your Google account

cloud_shell.sh

#!/usr/bin/env bash
# CLI for Google Cloud shell.
#
# Requirements:
# - gcloud
# - grep with Perl regexp support
# - curl

get_json_key () {
	echo $2 | grep -Po '"'$1'": *"?\K.*?(?=[ ",}])'
	# Use the one below if jq is installed
	#echo $2 | jq -r $1
}

get_instance_info () {
	ACCESS_TOKEN=$(gcloud auth print-access-token)
	RESPONSE=$(curl -sS -H "Authorization: Bearer $ACCESS_TOKEN" https://cloudshell.googleapis.com/v1alpha1/users/me/environments/default)
	STATE=$(get_json_key state "$RESPONSE")

	echo "Cloud Shell instance is $STATE"

	if [ $STATE == "DISABLED" ]; then
		start_instance
	fi

	USERNAME=$(get_json_key sshUsername "$RESPONSE")
	PORT=$(get_json_key sshPort "$RESPONSE")
	HOST=$(get_json_key sshHost "$RESPONSE")
}

start_instance () {
	RESPONSE=$(curl -sS -H "Authorization: Bearer $ACCESS_TOKEN" -X POST https://cloudshell.googleapis.com/v1alpha1/users/me/environments/default:start)
	STATE=$(get_json_key state "$RESPONSE")

	printf "Starting Cloud Shell instance..."
	while [ $STATE != "RUNNING" ]
	do
		RESPONSE=$(curl -sS -H "Authorization: Bearer $ACCESS_TOKEN" https://cloudshell.googleapis.com/v1alpha1/users/me/environments/default)
		STATE=$(get_json_key state "$RESPONSE")
		sleep 0.1s
	done
	printf "[Done]"
}

case $1 in
  login)
    gcloud auth login
    ;;

  ssh)
    get_instance_info
	shift
	SSH_OPTIONS=$@
	CMD="ssh -4 -p $PORT -i '~\.ssh\google_compute_engine' -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $SSH_OPTIONS $USERNAME@$HOST"
	echo $CMD
	eval $CMD
	;;

  info)
    get_instance_info
	echo "STATE: $STATE"
	echo "USERNAME: $USERNAME"
	echo "HOST: $HOST"
	echo "PORT: $PORT"
	;;
  *)
    echo -e "Usage:\n $0 {login|ssh|info} [optional args]"
    ;;
esac

How to use it

1. Authenticate
   ./cloud_shell.sh login

2. SSH into the Google Cloud Shell machine (you must have an authorized private SSH key in ~\.ssh\google_compute_engine)
   ./cloud_shell.sh ssh

Dependencies

• gcloud to start authentication
• curl for HTTP requests
• grep with Perl regular expressions support for naive JSON parsing