In the examples repository there is a skeleton template directory tree that can be used as a starting point for developing new models and processes. It contains these files:
skel/build.sbt
skel/src/main/scala/org/example/Example.scala
skel/src/main/resources/example.py
skel/src/main/resources/META-INF/services/uk.ac.ed.inf.mois.Model
skel/src/test/scala/org/example/ExampleTest.scala
skel/src/test/resources/example_test.py
The first one, build.sbt, contains instructions for the sbt build tool for how to compile the model. This is where any dependencies are listed as well as version information and so forth.
The actual source code for the model goes in the src/main sub
directory. In here is
Example.scala,
a scala source code file that implements the
model. The convention is to use a package name that is unique and
corresponds to a domain name that belongs to you. The source code goes
in a sub-directory that is this name, reversed. That is, for a package
called “foo.example.org” the files would go in
src/main/scala/org/example/foo.
The file in META-INF is important. It should contain the fully
qualified name(s) of your models, one per line. This file is how
the main Mois program, or sbt knows how to find your models to
run them.
Optionally, any other necessary files should be put in
src/main/resources. These can be any sort of file, but this is
mainly used for python scripting – the python source code goes
there.
The src/test sub-directory mirrors the main one and is where tests
for the model go. A minimal example is
ExampleTest.scala.
It is a very good idea to have a suite of tests that
verify that different parts of the model are working as expected. This
practice helps to find bugs and can help to make sure that when a change
is made that the change doesn’t also break other things that. The test
suite can also serve as useful supplementary documentation with
examples of how to use different parts of the model software.
The model can then be compiled with sbt compile and tested with sbt
test and run with sbt run in the usual way.