set of CircleCI resource classes

list_classes.py

#!/usr/bin/env python3

import re
from pathlib import Path

import yaml


def all_resource_classes(thing):
    if isinstance(thing, list):
        return {c for e in thing for c in all_resource_classes(e)}
    elif isinstance(thing, dict):
        s = set()
        for k, v in thing.items():
            if k == 'resource_class':
                if isinstance(v, dict):
                    s.add(v['default'])
                else:
                    s.add(v)
            else:
                s |= all_resource_classes(v)
        return s
    else:
        return set()


if __name__ == '__main__':
    text = Path('.circleci/config.yml').read_text()
    thing = yaml.load(text, Loader=yaml.Loader)
    for c in all_resource_classes(thing):
        if not re.match(r'^<< .* >>$', c):
            print(c)