authorize a new google cloud project. save its default application credentials, so that it's easy to switch between projects

new_gcp_project.sh

#@IgnoreInspection BashAddShebang

GCLOUD_DIR="$HOME/.config/gcloud"
: ${PROJECT_NAME?"Need to set PROJECT_NAME"}

if curl metadata.google.internal -i &> /dev/null; then
    echo "Running on GCE instance.  Skipping $PROJECT_NAME setup"
else
    # https://stackoverflow.com/a/28938235/3893740
    GREEN='\033[0;32m'
    COLOR_OFF='\033[0m'

    if [[ ! -f $GCLOUD_DIR/configurations/config_$PROJECT_NAME ]]; then
        echo -e "$GREEN"
        echo "################################################################################"
        echo "Creating new gcloud configuration for the GCP Project $PROJECT_NAME."
        echo "################################################################################"
        echo ""
        echo -e "$COLOR_OFF"  # end color scheme
        gcloud config configurations create $PROJECT_NAME
        echo -e "$GREEN"  # set color to green
        echo ""
        echo "################################################################################"
        echo "Running gcloud init, please follow instructions from.  In the following steps:"
        echo "I    Choose \"[1] Re-initialize this configuration [$PROJECT_NAME] with new settings\""
        echo "II   Choose to use appropriate email address"
        echo "III  Choose \"[#] $PROJECT_NAME\""
        echo "IV   Choose \"y\" for setting a default region".
        echo "V    Browser opens.  Login using same gmail address"
        echo "################################################################################"
        echo ""
        echo -e "$COLOR_OFF"  # end color scheme

        gcloud init
        gcloud auth application-default login
        cp $GCLOUD_DIR/application_default_credentials.json \
           $GCLOUD_DIR/application_default_credentials.json.$PROJECT_NAME
        echo "Finished setup for project $PROJECT_NAME"
    fi

    current_project=$( gcloud config list --format 'value(core.project)' 2> /dev/null )
    if [ "$current_project" != "$PROJECT_NAME" ]; then
      echo "Your current project is $current_project, but your config is set to $PROJECT_NAME. Please run $ switch_gcp_project $PROJECT_NAME"
    fi
fi