Best way to test if a systemd service is running in bash script

systemctl is-active application.service
systemctl is-enabled application.service
systemctl is-active --quiet service

will exit with status zero if service is active, non-zero otherwise, making it ideal for scripts:

systemctl is-active --quiet service && echo Service is running

References
https://www.digitalocean.com/community/tutorials/how-to-use-systemctl-to-manage-systemd-services-and-units
https://unix.stackexchange.com/questions/396630/the-proper-way-to-test-if-a-service-is-running-in-a-script