What is the canonical YAML naming style

Kubernetes using camelCase: https://kubernetes.io/docs/user-guide/jobs/

apiVersion, restartPolicy

CircleCI using snake_case: https://circleci.com/docs/1.0/configuration/

working_directory restore_cache, store_artifacts

Jenkins with dash-case: https://github.com/jenkinsci/yaml-project-plugin/blob/master/samples/google-cloud-storage/.jenkins.yaml

stapler-class

---

So it looks like projects and teams use their own conventions and there is no one definite standard.

Use the standard dictated by the surrounding software.

For example, in my current project the YAML file contains default values for Python attributes. Since the names used in YAML appear in the associated Python API, it is clear that on this particular project, the YAML names should obey the Python lower_case_with_underscores naming convention per PEP-8.

My next project might have a different prevailing naming convention, in which case I will use that in the associated YAML files.