Source code for ocrd_utils.introspect

"""
Utility functions to simplify access to data structures.
"""
import json
from functools import wraps
from pathlib import Path
from frozendict import frozendict
import atexit
from contextlib import ExitStack

# cannot use importlib.resources until we move to 3.9+ forimportlib.resources.files
import sys
if sys.version_info < (3, 10):
    import importlib_resources
else:
    import importlib.resources as importlib_resources

if sys.version_info < (3, 8):
    import importlib_metadata
else:
    import importlib.metadata as importlib_metadata

file_manager = ExitStack()
atexit.register(file_manager.close)

# Taken from https://github.com/OCR-D/core/pull/884


def freeze_args(func):
    """
    Transform mutable dictionary into immutable. Useful to be compatible with cache.
    Code taken from `this post <https://stackoverflow.com/a/53394430/1814420>`_
    """
    @wraps(func)
    def wrapped(*args, **kwargs):
        args = tuple([frozendict(arg) if isinstance(arg, dict) else arg for arg in args])
        kwargs = {k: frozendict(v) if isinstance(v, dict) else v for k, v in kwargs.items()}
        return func(*args, **kwargs)
    return wrapped





def membername(class_, val):
    """Convert a member variable/constant into a member name string."""
    return next((k for k, v in class_.__dict__.items() if v == val), str(val))




def set_json_key_value_overrides(obj, *kvpairs):
    for kv in kvpairs:
        k, v = kv
        try:
            obj[k] = json.loads(v)
        except json.decoder.JSONDecodeError:
            obj[k] = v
    return obj




def resource_filename(pkg : str, fname : str) -> Path:
    ref = importlib_resources.files(pkg) / fname
    return file_manager.enter_context(importlib_resources.as_file(ref))




def resource_string(pkg : str, fname : str) -> str:
    with open(resource_filename(pkg, fname), 'r', encoding='utf-8') as f:
        return f.read()




def dist_version(module : str) -> str:
    return importlib_metadata.version(module)