What is the purpose of the 'hiera_array' function in Puppet?

The 'hiera_array' function in Puppet is designed to retrieve all available values from the Hiera data store as an array. This function is particularly useful when you want to gather multiple values that are associated with a specific key across different levels of the data hierarchy. It allows you to aggregate values and return them in an array format, which can be further processed or utilized within your Puppet manifests.

This functionality is especially beneficial in scenarios where you have defined the same key in multiple location files in Hiera, and you want to collect all those values for a resource or class. By using 'hiera_array', you ensure that you're retrieving a comprehensive set of data rather than just a single entry or a specific type of data structure.

The other options are not aligned with the purpose of 'hiera_array'. For instance, retrieving a single value would require the use of a different function that focuses on specific entries, while writing values to Hiera or converting data formats falls outside the scope of what 'hiera_array' is intended to do.