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Diffstat (limited to 'utils/programming_utils.py')
| -rw-r--r-- | utils/programming_utils.py | 105 |
1 files changed, 0 insertions, 105 deletions
diff --git a/utils/programming_utils.py b/utils/programming_utils.py deleted file mode 100644 index a0a8fde..0000000 --- a/utils/programming_utils.py +++ /dev/null @@ -1,105 +0,0 @@ -# ------------------------------------------------------------------------- -# Copyright (c) 2015-2017 AT&T Intellectual Property -# -# Licensed under the Apache License, Version 2.0 (the "License"); -# you may not use this file except in compliance with the License. -# You may obtain a copy of the License at -# -# http://www.apache.org/licenses/LICENSE-2.0 -# -# Unless required by applicable law or agreed to in writing, software -# distributed under the License is distributed on an "AS IS" BASIS, -# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -# See the License for the specific language governing permissions and -# limitations under the License. -# -# ------------------------------------------------------------------------- -# - -import collections -import itertools - - -class DotDict(dict): - """A dot-dict mixin to be able to access a dictionary via dot notation - source: https://stackoverflow.com/questions/2352181/how-to-use-a-dot-to-access-members-of-dictionary - """ - __getattr__ = dict.get - __setattr__ = dict.__setitem__ - __delattr__ = dict.__delitem__ - - -class MetaSingleton(type): - """Singleton class (2nd Chapter) from Learning Python Design Patterns - 2nd ed. - Chetan Giridhar, Packt Publ. 2016""" - _instances = {} - - def __call__(cls, *args, **kwargs): - if cls not in cls._instances: - cls._instances[cls] = super(MetaSingleton, cls).__call__(*args, **kwargs) - return cls._instances[cls] - - -def namedtuple_with_defaults(typename, field_names, default_values=()): - """A namedtuple with default values -- Stack overflow recipe from Mark Lodato - http://stackoverflow.com/questions/11351032/named-tuple-and-optional-keyword-arguments - :param typename: Name for the class (same as for namedtuple) - :param field_names: Field names (same as for namedtuple) - :param default_values: Can be specified as a dictionary or as a list - :return: New namedtuple object - """ - T = collections.namedtuple(typename, field_names) - T.__new__.__defaults__ = (None,) * len(T._fields) - if isinstance(default_values, collections.Mapping): - prototype = T(**default_values) - else: - prototype = T(*default_values) - T.__new__.__defaults__ = tuple(prototype) - return T - - -def dot_notation(dict_like, dot_spec): - """Return the value corresponding to the dot_spec from a dict_like object - :param dict_like: dictionary, JSON, etc. - :param dot_spec: a dot notation (e.g. a1.b1.c1.d1 => a1["b1"]["c1"]["d1"]) - :return: the value referenced by the dot_spec - """ - attrs = dot_spec.split(".") # we split the path - parent = dict_like.get(attrs[0]) - children = ".".join(attrs[1:]) - if not (parent and children): # if no children or no parent, bail out - return parent - if isinstance(parent, list): # here, we apply remaining path spec to all children - return [dot_notation(j, children) for j in parent] - elif isinstance(parent, dict): - return dot_notation(parent, children) - else: - return None - - -def list_flatten(l): - """ - Flatten a complex nested list of nested lists into a flat list (DFS). - For example, [ [1, 2], [[[2,3,4], [2,3,4]], [3,4,5, 'hello']]] - will produce [1, 2, 2, 3, 4, 2, 3, 4, 3, 4, 5, 'hello'] - """ - return list(itertools.chain(*[list_flatten(j) if isinstance(j, list) else [j] for j in l])) - - -def inverted_dict(keys: list, key_val_dict: dict) -> dict: - """ - Get val -> [keys] mapping for the given keys using key_val_dict - :param keys: the keys we are interested in (a list) - :param key_val_dict: the key -> val mapping - :return: inverted dictionary of val -> [keys] (for the subset dict of given keys) - """ - res = {} - all_tuples = ((k, key_val_dict[k] if k in key_val_dict else 'no-parent-' + k) for k in keys) - for k, v in all_tuples: - if v in res: - res[v].append(k) - else: - res[v] = [k] - # making sure to remove duplicate keys - res = dict((v, list(set(k_list))) for v, k_list in res.items()) - return res |