NewValueOrPath returns a new ValueOrPath according to the arguments: - s is either the value itself or a path to a file containing the value (the value is then read as a string) - fileOnly indicates if s must be a path; set it to true for values which should be passed only in files, either for security purposes (k8s secret mounted as a volume), or when the file is needed by whichever library (e.g.

0 is a valid port, need another invalid value indicating "ignore me".

ValueOrPath is typically used to read Kubernetes secrets (https://kubernetes.io/docs/concepts/configuration/secret/), which can be provided to pods using either environment variables or mounted volumes.