GetIntOrFatal returns value of environment variable that is expected to be an int, otherwise logs a Fatal error (and exits).

GetListOrFatal returns the key's value as a list or logs a Fatal error (and exits) The value is expected to be a csv NOTE: if the value is not csv, it is returned as is in a list with the original string as the only element in the list.

GetLogLevel returns the loglevet or panics.

GetOrFatal returns the key's value or logs a Fatal error (and exits).

GetRequired gets the value for the key, or an error if it is not set.

GetTruthyOrFatal returns true if key is set to a value that is truthy.

ReadIndirectOrFatal reads filename and uses it to read a value from the file.