Automate ABNF to python namespace patterns

[ahouseholder]

In #898, we added a new ABNF file src/ssvc/utils/ssvc_namespace_pattern.abnf
that was used to generate the namespace regex patterns in src/ssvc/utils/patterns.py. However, this conversion was a one-shot static event.

I'd like us to be able to dynamically read the .abnf file and have that populate the items in patterns.py automatically at run time. I believe this is possible using library methods from abnf-to-regex.

[bernhardreiter]

Added aas-core-works/abnf-to-regexp#44 to fix the repetition regex difference in upstream first.

[bernhardreiter]

Meanwhile https://github.com/aas-core-works/abnf-to-regexp/releases/tag/v1.2.0 has what we need, so I'll prepare a merge request.

[bernhardreiter]

I'd like us to be able to dynamically read the .abnf file and have that populate the items in patterns.py automatically at run time.

Do you prefer to read the .abnf file each time at runtime?
(As opposed to have a "make regenerate" step that creates the .py file.)

I believe this is possible using library methods from abnf-to-regex.

Looking at https://github.com/aas-core-works/abnf-to-regexp/blob/1fc56a6a93c0aa777f641828788595535dbbba94/abnf_to_regexp/main.py#L48 and deeper, it seems that abpf-to-regexp does not offer library functions that return the generated patterns. It generates strings. In order to get this into the code dynamically would mean to exec() them in python.

The parsing and exec() step in runtime will add an overhead to the startup time of ssvc.

Instead a classic Makefile rule could be used that creates a new abnf_pattern.py file each time the source .abnf file has been changed.

[bernhardreiter]

See #1065 for the Makefile based approach.

[bernhardreiter]

to get this into the code dynamically would mean to exec() them in python.

But it can be done. See #1067 for the runtime parsing approach.
Chose the one you prefer.