This is done through a new ``tech-dep`` attribute in the
definition of the relation (done in the ``provide`` part of
the ``metadata.yml`` of a charm).
This replaces the ``reverse-tech-dep`` as it no allows 3 values.
The default one is ``True`` which simply allow the creation of
a ``link`` in the ``docker-compose`` file.
The value ``False`` will prevent creation of any ``link``, and the
``reversed`` value will reverse the ``link`` created.
Valentin Lab
7c77658ff8