utils.py

# encoding: utf-8
"""

"""
__author__ = "Richard Smith"
__date__ = "13 Sep 2021"
__copyright__ = "Copyright 2018 United Kingdom Research and Innovation"
__license__ = "BSD - see LICENSE file in top-level package directory"
__contact__ = "richard.d.smith@stfc.ac.uk"

# Taken from https://github.com/cedadev/stac-generator/blob/master/stac_generator/core/utils.py


# Python imports
import collections


def dict_merge(*args, add_keys=True) -> dict:
    assert len(args) >= 2, "dict_merge requires at least two dicts to merge"

    # Make a copy of the root dict
    rtn_dct = args[0].copy()

    merge_dicts = args[1:]

    for merge_dct in merge_dicts:

        if add_keys is False:
            merge_dct = {
                key: merge_dct[key] for key in set(rtn_dct).intersection(set(merge_dct))
            }

        for k, v in merge_dct.items():

            # This is a new key. Add as is.
            if not rtn_dct.get(k):
                rtn_dct[k] = v

            # This is an existing key with mismatched types
            elif k in rtn_dct and type(v) != type(rtn_dct[k]):
                raise TypeError(
                    f"Overlapping keys exist with different types: original is {type(rtn_dct[k])}, new value is {type(v)}"
                )

            # Recursive merge the next level
            elif isinstance(rtn_dct[k], dict) and isinstance(
                merge_dct[k], collections.abc.Mapping
            ):
                rtn_dct[k] = dict_merge(rtn_dct[k], merge_dct[k], add_keys=add_keys)

            # If the item is a list, append items avoiding duplictes
            elif isinstance(v, list):
                for list_value in v:
                    if list_value not in rtn_dct[k]:
                        rtn_dct[k].append(list_value)
            else:
                rtn_dct[k] = v

    return rtn_dct