Source code for calliope.core.attrdict

Copyright (C) 2013-2018 Calliope contributors listed in AUTHORS.
Licensed under the Apache 2.0 License (see LICENSE file).

Implements the AttrDict class (a subclass of regular dict)
used for managing model configuration.


import io
from pathlib import Path

import numpy as np
import ruamel.yaml as ruamel_yaml

from import relative_path
from calliope.core.util.logging import logger

class __Missing(object):
    def __nonzero__(self):
        return False

_MISSING = __Missing()

def _yaml_load(src):
    """Load YAML from a file object or path with useful parser errors"""
    if not isinstance(src, str):
            src_name =
        except AttributeError:
            src_name = '<yaml stringio>'
        # Force-load file streams as that allows the parser to print
        # much more context when it encounters an error
        src =
        src_name = '<yaml string>'
        result = ruamel_yaml.safe_load(src)
        if not isinstance(result, dict):
            raise ValueError('Could not parse {} as YAML'.format(src_name))
        return result
    except ruamel_yaml.YAMLError:
            'Parser error when reading YAML '
            'from {}.'.format(src_name)

[docs]class AttrDict(dict): """ A subclass of ``dict`` with key access by attributes:: d = AttrDict({'a': 1, 'b': 2}) d.a == 1 # True Includes a range of additional methods to read and write to YAML, and to deal with nested keys. """ __getattr__ = dict.__getitem__ __setattr__ = dict.__setitem__ def __init__(self, source_dict=None): super().__init__() if source_dict is not None: if isinstance(source_dict, dict): self.init_from_dict(source_dict) else: raise ValueError('Must pass a dict to AttrDict')
[docs] def copy(self): """Override copy method so that it returns an AttrDict""" return AttrDict(self.as_dict().copy())
[docs] def init_from_dict(self, d): """ Initialize a new AttrDict from the given dict. Handles any nested dicts by turning them into AttrDicts too:: d = AttrDict({'a': 1, 'b': {'x': 1, 'y': 2}}) d.b.x == 1 # True """ for k, v in d.items(): # First, keys must be strings, not ints if isinstance(k, int): k = str(k) # Now, assign to the key, handling nested AttrDicts properly if isinstance(v, dict): self.set_key(k, AttrDict(v)) elif isinstance(v, list): # Modifying the list in-place so that if it is a modified # list subclass, e.g. CommentedSeq, it is not killed for i in range(len(v)): if isinstance(v[i], dict): v[i] = AttrDict(v[i]) self.set_key(k, v) else: self.set_key(k, v)
@classmethod def _resolve_imports(cls, loaded, resolve_imports, base_path=None): if isinstance(resolve_imports, bool) and resolve_imports is True and 'import' in loaded: loaded_dict = loaded elif isinstance(resolve_imports, str) and resolve_imports + '.import' in loaded.keys_nested(): loaded_dict = loaded.get_key(resolve_imports) else: # Return right away if no importing to be done return loaded # If we end up here, we have something to import imports = loaded_dict.get_key('import') if not isinstance(imports, list): raise ValueError('`import` must be a list.') for k in imports: if base_path: path = relative_path(base_path, k) else: path = k imported = cls.from_yaml(path) # loaded is added to imported (i.e. it takes precedence) imported.union(loaded_dict) loaded_dict = imported # 'import' key itself is no longer needed loaded_dict.del_key('import') if isinstance(resolve_imports, str): loaded.set_key(resolve_imports, loaded_dict) else: loaded = loaded_dict return loaded
[docs] @classmethod def from_yaml(cls, f, resolve_imports=True): """ Returns an AttrDict initialized from the given path or file object ``f``, which must point to a YAML file. The path can be a string or a pathlib.Path. Parameters ---------- f : str or pathlib.Path resolve_imports : bool or str, optional If ``resolve_imports`` is True, top-level ``import:`` statements are resolved recursively. If ``resolve_imports is False, top-level ``import:`` statements are treated like any other key and not further processed. If ``resolve_imports`` is a string, such as ``foobar``, import statements underneath that key are resolved, i.e. ``foobar.import:``. When resolving import statements, anything defined locally overrides definitions in the imported file. """ if isinstance(f, str) or isinstance(f, Path): with open(f, 'r') as src: loaded = cls(_yaml_load(src)) else: loaded = cls(_yaml_load(f)) loaded = cls._resolve_imports(loaded, resolve_imports, base_path=f) return loaded
[docs] @classmethod def from_yaml_string(cls, string, resolve_imports=True): """ Returns an AttrDict initialized from the given string, which must be valid YAML. """ loaded = cls(_yaml_load(string)) loaded = cls._resolve_imports(loaded, resolve_imports) return loaded
[docs] def set_key(self, key, value): """ Set the given ``key`` to the given ``value``. Handles nested keys, e.g.:: d = AttrDict() d.set_key('', 1) == 1 # True """ if isinstance(value, dict) and not isinstance(value, AttrDict): value = AttrDict(value) if '.' in key: key, remainder = key.split('.', 1) try: self[key].set_key(remainder, value) except KeyError: self[key] = AttrDict() self[key].set_key(remainder, value) except AttributeError: if self[key] is None: # If the value is None, we replace it self[key] = AttrDict() self[key].set_key(remainder, value) # Else there is probably something there, and we don't just # want to overwrite so stop and warn the user else: raise KeyError('Cannot set nested key on non-dict key.') else: self[key] = value
[docs] def get_key(self, key, default=_MISSING): """ Looks up the given ``key``. Like set_key(), deals with nested keys. If default is anything but ``_MISSING``, the given default is returned if the key does not exist. """ if '.' in key: # Nested key of form "" key, remainder = key.split('.', 1) if default != _MISSING: try: value = self[key].get_key(remainder, default) except KeyError: # subdict exists, but doesn't contain key return default except AttributeError: # key points to non-dict thing, so no get_key attribute return default else: value = self[key].get_key(remainder) else: # Single, non-nested key of form "foo" if default != _MISSING: return self.get(key, default) else: return self[key] return value
[docs] def del_key(self, key): """Delete the given key. Properly deals with nested keys.""" if '.' in key: key, remainder = key.split('.', 1) try: del self[key][remainder] except KeyError: self[key].del_key(remainder) # If we removed the last subkey, delete the parent key too if len(self[key].keys()) == 0: del self[key] else: del self[key]
[docs] def as_dict(self, flat=False): """ Return the AttrDict as a pure dict (with nested dicts if necessary). """ if flat: return self.as_dict_flat() else: return self.as_dict_nested()
def as_dict_nested(self): d = {} for k, v in self.items(): if isinstance(v, AttrDict): d[k] = v.as_dict() elif isinstance(v, list): d[k] = [ i if not isinstance(i, AttrDict) else i.as_dict() for i in v] else: d[k] = v return d def as_dict_flat(self): d = {} keys = self.keys_nested() for k in keys: d[k] = self.get_key(k) return d
[docs] def to_yaml(self, path=None): """ Saves the AttrDict to the ``path`` as a YAML file, or returns a YAML string if ``path`` is None. """ result = self.copy() yaml_ = ruamel_yaml.YAML() yaml_.indent = 2 yaml_.block_seq_indent = 0 # Numpy objects should be converted to regular Python objects, # so that they are properly displayed in the resulting YAML output for k in result.keys_nested(): # Convert numpy numbers to regular python ones v = result.get_key(k) if isinstance(v, np.floating): result.set_key(k, float(v)) elif isinstance(v, np.integer): result.set_key(k, int(v)) # Lists are turned into seqs so that they are formatted nicely elif isinstance(v, list): result.set_key(k, yaml_.seq(v)) result = result.as_dict() if path is not None: with open(path, 'w') as f: yaml_.dump(result, f) else: stream = io.StringIO() yaml_.dump(result, stream) return stream.getvalue()
[docs] def keys_nested(self, subkeys_as='list'): """ Returns all keys in the AttrDict, sorted, including the keys of nested subdicts (which may be either regular dicts or AttrDicts). If ``subkeys_as='list'`` (default), then a list of all keys is returned, in the form ``['a', 'b.b1', 'b.b2']``. If ``subkeys_as='dict'``, a list containing keys and dicts of subkeys is returned, in the form ``['a', {'b': ['b1', 'b2']}]``. """ keys = [] for k, v in sorted(self.items()): # Check if dict instance (which AttrDict is too), # and for non-emptyness of the dict if isinstance(v, dict) and v: if subkeys_as == 'list': keys.extend([ k + '.' + kk for kk in v.keys_nested() ]) elif subkeys_as == 'dict': keys.append({k: v.keys_nested( subkeys_as=subkeys_as) }) else: keys.append(k) return keys
[docs] def union( self, other, allow_override=False, allow_replacement=False, allow_subdict_override_with_none=False): """ Merges the AttrDict in-place with the passed ``other`` AttrDict. Keys in ``other`` take precedence, and nested keys are properly handled. If ``allow_override`` is False, a KeyError is raised if other tries to redefine an already defined key. If ``allow_replacement``, allow "_REPLACE_" key to replace an entire sub-dict. If ``allow_subdict_override_with_none`` is False (default), a key of the form ``this.that: None`` in other will be ignored if subdicts exist in self like `` 1``, rather than wiping them. """ self_keys = self.keys_nested() other_keys = other.keys_nested() if allow_replacement: WIPE_KEY = '_REPLACE_' override_keys = [k for k in other_keys if WIPE_KEY not in k] wipe_keys = [k.split('.' + WIPE_KEY)[0] for k in other_keys if WIPE_KEY in k] else: override_keys = other_keys wipe_keys = [] for k in override_keys: if not allow_override and k in self_keys: raise KeyError('Key defined twice: {}'.format(k)) else: other_value = other.get_key(k) # If other value is None, and would overwrite an entire subdict, # we skip it if not (other_value is None and isinstance(self.get_key(k, None), AttrDict)): self.set_key(k, other_value) for k in wipe_keys: self.set_key(k, other.get_key(k + '.' + WIPE_KEY))