mcutils/storage.py

268 lines
8.8 KiB
Python

""" npy/npz/hdf5 file based storage;
this modules adds the possibility to dump and load objects in files and
a more convenient was of accessing the data via the .attributedict thanks
to the DataStorage class """
import numpy as np
import os
import h5py
import collections
import logging
log = logging.getLogger(__name__)
def unwrapArray(a,recursive=True,readH5pyDataset=True):
""" This function takes an object (like a dictionary) and recursively
unwraps it solving issues like:
* the fact that many objects are packaged as 0d array
This funciton has also some specific hack for handling h5py limits:
* handle the None python object
* numpy unicode ...
"""
# is h5py dataset convert to array
if isinstance(a,h5py.Dataset) and readH5pyDataset: a = a[...]
if isinstance(a,h5py.Dataset) and a.shape == (): a = a[...]
if isinstance(a,h5py.Group) and "IS_LIST_OF_ARRAYS" in a.attrs:
items = list(a.keys())
items.sort()
a = np.asarray( [a[item][...] for item in items] )
if isinstance(a,np.ndarray) and a.ndim == 0 : a = a.item()
if isinstance(a,np.ndarray) and a.dtype.char == "S": a = a.astype(str)
if recursive:
if "items" in dir(a): # dict, h5py groups, npz file
a = dict(a); # convert to dict, otherwise can't asssign values
for key,value in a.items(): a[key] = unwrapArray(value)
elif isinstance(a,(list,tuple)):
a = [unwrapArray(element) for element in a]
else:
pass
if isinstance(a,dict): a = DataStorage(a)
# restore None that cannot be saved in h5py
if isinstance(a,str) and a == "NONE_PYTHON_OBJECT": a = None
# h5py can't save numpy unicode
if isinstance(a,np.ndarray) and a.dtype.char == "S": a = a.astype(str)
return a
def dictToH5Group(d,group):
""" helper function that transform (recursive) a dictionary into an
hdf group by creating subgroups """
for key,value in d.items():
if isinstance(value,dict):
group.create_group(key)
dictToH5Group(value,group[key])
else:
# h5py can't handle numpy unicode arrays
if isinstance(value,np.ndarray) and value.dtype.char == "U":
value = np.asarray([vv.encode('ascii') for vv in value])
group[key] = value
# check if it is list of array
elif isinstance(value,np.ndarray) and value.ndim == 1 and isinstance(value[0],np.ndarray):
group.create_group(key)
group[key].attrs["IS_LIST_OF_ARRAYS"] = True
for index,array in enumerate(value): group["%s/index%05d"%(key,index)] = array
# h5py can't save None
elif value is None:
group[key] = "NONE_PYTHON_OBJECT"
else:
try:
group[key] = value
except TypeError:
log.error("Can't save %s"%(key))
def dictToH5(h5,d):
""" Save a dictionary into an hdf5 file
TODO: add capability of saving list of array
h5py is not capable of handling dictionaries natively"""
h5 = h5py.File(h5,mode="w")
# group = h5.create_group("/")
dictToH5Group(d,h5["/"])
h5.close()
def h5ToDict(h5,readH5pyDataset=True):
""" Read a hdf5 file into a dictionary """
with h5py.File(h5,"r") as h:
ret = unwrapArray(h,recursive=True,readH5pyDataset=readH5pyDataset)
return ret
def npzToDict(npzFile):
with np.load(npzFile) as npz: d = dict(npz)
d = unwrapArray(d,recursive=True)
return d
def npyToDict(npyFile):
d = unwrapArray( np.load(npyFile).item() ,recursive=True)
return d
def dictToNpz(npzFile,d): np.savez(npzFile,**d)
def dictToNpy(npyFile,d): np.save(npyFile,d)
def objToDict(o,recursive=True):
""" convert a DictWrap to a dictionary (useful for saving); it should work for other objects too
TODO: this function does not catch a list of DataStorage instances like
objToDict( ( DataStorage(), DataStorage() ) )
is not converted !!
"""
if "items" not in dir(o): return o
d = dict()
for k,v in o.items():
try:
d[k] = objToDict( v )
except Exception as e:
log.info("In objToDict, could not convert key %s to dict, error was"%\
(k,e))
d[k] = v
return d
def read(fname):
extension = os.path.splitext(fname)[1]
log.info("Reading storage file %s"%fname)
if extension == ".npz":
return DataStorage(npzToDict(fname))
elif extension == ".npy":
return DataStorage(npyToDict(fname))
elif extension == ".h5":
return DataStorage(h5ToDict(fname))
else:
raise ValueError("Extension must be h5, npy or npz, it was %s"%extension)
def save(fname,d):
# make sure the object is dict (recursively) this allows reading it
# without the DataStorage module
d = objToDict(d,recursive=True)
d['filename'] = fname
extension = os.path.splitext(fname)[1]
log.info("Saving storage file %s"%fname)
try:
if extension == ".npz":
return dictToNpz(fname,d)
elif extension == ".h5":
return dictToH5(fname,d)
elif extension == ".npy":
return dictToNpy(fname,d)
else:
raise ValueError("Extension must be h5, npy or npz, it was %s"%extension)
except Exception as e:
log.exception("Could not save %s"%fname)
class DataStorage(dict):
""" Storage for dict like object.
recursive : bool
recursively convert dict-like objects to DataStorage
It can save data to file (format npy,npz or h5)
To initialize it:
data = DataStorage( a=(1,2,3),b="add",filename='store.npz' )
# recursively by default
# data.a will be a DataStorage instance
data = DataStorage( a=dict( b = 1)) );
# data.a will be a dictionary
data = DataStorage( a=dict( b = 1),recursive=False )
# reads from file if it exists
data = DataStorage( 'mysaveddata.npz' ) ;
DOES NOT READ FROM FILE (even if it exists)!!
data = DataStorage( filename = 'mysaveddata.npz' );
create empty storage (with default filename)
data = DataStorage()
"""
def __init__(self,*args,filename='data_storage.npz',recursive=True,**kwargs):
# self.filename = kwargs.pop('filename',"data_storage.npz")
self.filename = filename
self._recursive = recursive
# interpret kwargs as dict if there are
if len(kwargs) != 0:
fileOrDict = dict(kwargs)
elif len(kwargs)==0 and len(args)>0:
fileOrDict = args[0]
else:
fileOrDict = dict()
d = dict(); # data dictionary
if isinstance(fileOrDict,dict):
d = fileOrDict
elif isinstance(fileOrDict,str):
if os.path.isfile(fileOrDict):
d = read(fileOrDict)
else:
self.filename=fileOrDict
d = dict()
else:
raise ValueError("Invalid DataStorage definition")
if recursive:
for k in d.keys():
if not isinstance(d[k],DataStorage) and isinstance(d[k],dict):
d[k] = DataStorage(d[k])
# allow accessing with .data, .delays, etc.
for k,v in d.items(): setattr(self,k,v)
# allow accessing as proper dict
self.update( **dict(d) )
def __setitem__(self, key, value):
#print("__setitem__")
setattr(self,key,value)
super().__setitem__(key, value)
def __setattr__(self, key, value):
""" allows to add fields with data.test=4 """
# check if attr exists is essential (or it fails when defining an instance)
if hasattr(self,"_recursive") and self._recursive and \
isinstance(value,(dict,collections.OrderedDict)): value = DataStorage(value)
super().__setitem__(key, value)
super().__setattr__(key,value)
def __delitem__(self, key):
delattr(self,key)
super().__delitem__(key)
def __str__(self):
keys = list(self.keys())
keys.sort()
return "DataStorage obj containing: %s" % ",".join(keys)
def __repr__(self):
keys = list(self.keys())
keys.sort()
if len(keys) == 0: return "Empty DataStorage"
nchars = max(map(len,keys))
fmt = "%%%ds %%s" % (nchars)
s = ["DataStorage obj containing (sorted): ",]
for k in keys:
if k[0] == "_": continue
obj = self[k]
if isinstance(obj,(list,tuple,np.ndarray)) and all( [isinstance(v,np.ndarray) for v in obj]) and obj.ndim == 1:
value_str = "list of arrays, shapes " + ",".join([str(v.shape) for v in obj[:5]]) + " ..."
elif isinstance(obj,np.ndarray):
value_str = "array, size %s, type %s"% ("x".join(map(str,obj.shape)),obj.dtype)
elif isinstance(obj,DataStorage):
value_str = str(obj)[:50]
elif isinstance(obj,(str,DataStorage)):
value_str = obj[:50]
elif self[k] is None:
value_str = "None"
else:
value_str = str(self[k])
if len(str(obj))>50: value_str += " ..."
s.append( fmt % (k,value_str) )
return "\n".join(s)
def keys(self):
keys = list(super().keys())
keys = [k for k in keys if k != 'filename' ]
keys = [k for k in keys if k[0] != '_' ]
return keys
def save(self,fname=None):
if fname is None: fname = self.filename
assert fname is not None
save(fname,self)