Auto-keyword class generator system

What it is

The PyDyna auto-keyword class generator system generates python classes for dyna keywords based on specifications in kwd.json, manifest.json, and additional-cards.json It is implemented in codegen/generate.py and has a command line interface.

To use

It is recommended to use a virtual environment

• Install dependencies: pip install .[codegen]

• To run the code generation system for all classes: python codegen/generate.py -o /path/to/keyword_classes

• To run the code generation system for a single keyword, e.g. SECTION_SHELL: python codegen/generate.py -k SECTION_SHELL

• To remove all the generated code: python codegen/generate.py -c

How it works

The class generator uses Jinja templates to generate three distinct things:

• Python classes
• Import machinery
• keyword to type mapping

The python classes are what users of PyDyna interact with directly. The import machinery produces auto_keywords.py, which contains a list of import statements that import classes from the Python files where they are defined. The keyword to type mapping produces a dictionary mapping the keyword name with the python class that defines it.

The primary specification for keywords is found in kwd.json. It contains basic definitions for most keywords, including their cards and fields (which are defined by offset, name, default value, option, width, and helpstring). kwd.json must not be modified by hand, it is produced by machine in a process that is external to PyDyna.

While this specification is expansive, providing definitions for thousands of keywords, not all information pertaining to a keyword can be found there. In addition, there are some errors in that specification. Due to this, manifest.json and additional-cards.json contain that information that either supplements or corrects the information in kwd.json.

Corrections include: - fixing the order of cards ("reorder-card") - skipping an unnecessary card ("skip-card") - changing the name of a subkeyword ("override-subkeyword") - changing the definition of a field ("override-field") - replacing a card ("replace-card") - inserting a card ("insert-card") - changing the name of a python property ("rename-property")

Supplements include: - adding aliases - see Appendix A - Aliasing - cards that repeat, handled as a two dimensional table ("table-card") - A field represented as a one-dimensional array that repeat across cards ("series-card") - A set of adjacent cards with their own specification. These may repeat ("card-set") - A card that is only active under a condition ("conditional-card") - A set of adjacent cards that repeat, handled as a two dimensional table ("table-card-group") - Adding option cards ("add-option") - A field shared across multiple cards with only one meaning ("shared-field")

Appendix A

Aliasing

In some cases, two keywords are defined in exactly the same way and have the same meaning. This is called an alias. Examples of this are MAT_058 and MAT_LAMINATED_COMPOSITE_FABRIC. In such cases, the class generator will generate two classes, but one of the classes will alias the behavior of the other, the only difference being the name of the keyword. In the case of MAT_058 and its alias, both keywords are defined in kwd.json, so one of them will be ignored by the code generator. It is possible for only one of the two keywords to be defined in kwd.json, such as is the case for SET_NODE and SET_NODE_LIST. In that case, the class generator will produce the same effect, except that it does not need to ignore anything in kwd.json.