Go-Smart Simulation Model Families
==================================

Families represent groups of workflows that are simulated in
approximately the same way, or at least by using the same tools. This is
slightly more specific than a workflow as, for example, the Docker
workflow has a separate family for each Docker image. It corresponds
more accurately to a single configuration system. This comprises a pair:
a subclass of ``gssa.family.Family`` that contains instructions for
interpreting `GSSA-XML <gssa-xml>`__ for this type of simulation and
writing any necessary tool-specific configuration files, and the
simulation tools themselves.

Two examples are `GSSF <https://go-smart.github.io/goosefoot/overview/>`__,
which is also a fully fledged workflow, and
`FEniCS <docker/fenics>`__, which depends on pre-meshing by the `GSSF
CGAL mesher component <https://go-smart.github.io/goosefoot-mesher-cgal/>`__.

To find families, the ``gssa.family`` module scans for files in the
directory of the ``gssa.families`` module.

**TODO**: extend this to user-configurable locations.

**Note**: family modules are run as part of the Python server - this
means they are privileged and should only be included from highly
*trusted* sources, as with other codes running as ``www-data``. They are
not sandboxed or intended to be user-supplied, but constitute a basic
plug-in framework. The longer-term intention is to migrate to a proper
plug-in framework, where community developed families may be added in,
running as an unprivileged user. Of course, this would still require a
higher level of trust than given to external user code, which only runs
sandboxed in Docker.