Hiera provides an interesting function called
hiera_include, which allows users to include all the classes defined for a given key.
This, in practice, exploits the Hiera flexibility to provide classes to nodes as an External Node Classifier does.
It's enough to place the following line in our
site.pp file at
Define in our data sources a
classes key with an array of the classes to be included.
In a YAML-based backend, it would look like the following:
--- classes: - apache - mysql - php
This is exactly the same as having some declarations in our
site.pp as follows:
include apache include mysql include php
classes key (can have any name, but
classes is a standard de facto) contains ...