def __init__(self,
store=LocalBinaryStore(path_format=''),
incoming_val_trans_for_key=imdict(dflt_incoming_val_trans_for_key),
outgoing_val_trans_for_key=imdict(dflt_outgoing_val_trans_for_key),
dflt_incoming_val_trans=identity_method,
func_key=lambda k: os.path.splitext(k)[1]):
self.store = store
self.incoming_val_trans_for_key = incoming_val_trans_for_key
self.outgoing_val_trans_for_key = outgoing_val_trans_for_key
self.dflt_incoming_val_trans = dflt_incoming_val_trans
self.func_key = func_key
def set_obj(k, v, store=LocalBinaryStore(path_format=''),
outgoing_val_trans_for_key=imdict(dflt_outgoing_val_trans_for_key),
func_key=lambda k: os.path.splitext(k)[1]):
"""A quick way to get an object, with default... everything (but the key, you know, a clue of what you want)"""
trans_func = outgoing_val_trans_for_key.get(func_key(k), dflt_outgoing_val_trans_for_key)
store[k] = trans_func(v)
def get_obj(k, store=LocalBinaryStore(path_format=''),
incoming_val_trans_for_key=imdict(dflt_incoming_val_trans_for_key),
dflt_incoming_val_trans=identity_method,
func_key=lambda k: os.path.splitext(k)[1]):
"""A quick way to get an object, with default... everything (but the key, you know, a clue of what you want)"""
trans_func = (incoming_val_trans_for_key or {}).get(func_key(k), dflt_incoming_val_trans)
return trans_func(store[k])
class MiscReaderMixin:
"""Mixin to transform incoming vals according to the key their under.
Warning: If used as a subclass, this mixin should (in general) be placed before the store
>>> # make a reader that will wrap a dict
>>> class MiscReader(MiscReaderMixin, dict):
... def __init__(self, d,
... incoming_val_trans_for_key=None,
... dflt_incoming_val_trans=None,
... func_key=None):
... dict.__init__(self, d)
... MiscReaderMixin.__init__(self, incoming_val_trans_for_key, dflt_incoming_val_trans, func_key)
...
>>>
>>> incoming_val_trans_for_key = dict(
... MiscReaderMixin._incoming_val_trans_for_key, # take the existing defaults...
... **{'.bin': lambda v: [ord(x) for x in v.decode()], # ... override how to handle the .bin extension
... '.reverse_this': lambda v: v[::-1] # add a new extension (and how to handle it)
... })
>>>
>>> import pickle
>>> d = {
... 'a.bin': b'abc123',
... 'a.reverse_this': b'abc123',
... 'a.csv': b'event,year\\n Magna Carta,1215\\n Guido,1956',
... 'a.txt': b'this is not a text',
... 'a.pkl': pickle.dumps(['text', [str, map], {'a list': [1, 2, 3]}]),
... 'a.json': '{"str": "field", "int": 42, "float": 3.14, "array": [1, 2], "nested": {"a": 1, "b": 2}}',
... }
>>>
>>> s = MiscReader(d=d, incoming_val_trans_for_key=incoming_val_trans_for_key)
>>> list(s)
['a.bin', 'a.reverse_this', 'a.csv', 'a.txt', 'a.pkl', 'a.json']
>>> s['a.bin']
[97, 98, 99, 49, 50, 51]
>>> s['a.reverse_this']
b'321cba'
>>> s['a.csv']
[['event', 'year'], [' Magna Carta', '1215'], [' Guido', '1956']]
>>> s['a.pkl']
['text', [<class 'str'>, <class 'map'>], {'a list': [1, 2, 3]}]
>>> s['a.json']
{'str': 'field', 'int': 42, 'float': 3.14, 'array': [1, 2], 'nested': {'a': 1, 'b': 2}}
"""
_func_key = lambda self, k: os.path.splitext(k)[1]
_dflt_incoming_val_trans = staticmethod(identity_method)
_incoming_val_trans_for_key = imdict(dflt_incoming_val_trans_for_key)
def __init__(self, incoming_val_trans_for_key=None,
dflt_incoming_val_trans=None,
func_key=None):
if incoming_val_trans_for_key is not None:
self._incoming_val_trans_for_key = incoming_val_trans_for_key
if dflt_incoming_val_trans is not None:
self._dflt_incoming_val_trans = dflt_incoming_val_trans
if func_key is not None:
self._func_key = func_key
def __getitem__(self, k):
func_key = self._func_key(k)
trans_func = self._incoming_val_trans_for_key.get(func_key, self._dflt_incoming_val_trans)
return trans_func(super().__getitem__(k))