import json as _json
import textwrap
import numpy as np
from .abc import Codec
from .compat import ensure_text
[docs]class JSON(Codec):
"""Codec to encode data as JSON. Useful for encoding an array of Python objects.
.. versionchanged:: 0.6
The encoding format has been changed to include the array shape in the encoded
data, which ensures that all object arrays can be correctly encoded and decoded.
Examples
--------
>>> import numcodecs
>>> import numpy as np
>>> x = np.array(['foo', 'bar', 'baz'], dtype='object')
>>> codec = numcodecs.JSON()
>>> codec.decode(codec.encode(x))
array(['foo', 'bar', 'baz'], dtype=object)
See Also
--------
numcodecs.pickles.Pickle, numcodecs.msgpacks.MsgPack
"""
codec_id = 'json2'
def __init__(self, encoding='utf-8', skipkeys=False, ensure_ascii=True,
check_circular=True, allow_nan=True, sort_keys=True, indent=None,
separators=None, strict=True):
self._text_encoding = encoding
if separators is None:
# ensure separators are explicitly specified, and consistent behaviour across
# Python versions, and most compact representation if indent is None
if indent is None:
separators = ',', ':'
else:
separators = ', ', ': '
separators = tuple(separators)
self._encoder_config = dict(skipkeys=skipkeys, ensure_ascii=ensure_ascii,
check_circular=check_circular, allow_nan=allow_nan,
indent=indent, separators=separators,
sort_keys=sort_keys)
self._encoder = _json.JSONEncoder(**self._encoder_config)
self._decoder_config = dict(strict=strict)
self._decoder = _json.JSONDecoder(**self._decoder_config)
[docs] def encode(self, buf):
try:
buf = np.asarray(buf)
except ValueError:
buf = np.asarray(buf, dtype=object)
items = np.atleast_1d(buf).tolist()
items.append(buf.dtype.str)
items.append(buf.shape)
return self._encoder.encode(items).encode(self._text_encoding)
[docs] def decode(self, buf, out=None):
items = self._decoder.decode(ensure_text(buf, self._text_encoding))
dec = np.empty(items[-1], dtype=items[-2])
if not items[-1]:
dec[...] = items[0]
else:
dec[:] = items[:-2]
if out is not None:
np.copyto(out, dec)
return out
else:
return dec
[docs] def get_config(self):
config = dict(id=self.codec_id, encoding=self._text_encoding)
config.update(self._encoder_config)
config.update(self._decoder_config)
return config
def __repr__(self):
params = ['encoding=%r' % self._text_encoding]
for k, v in sorted(self._encoder_config.items()):
params.append('{}={!r}'.format(k, v))
for k, v in sorted(self._decoder_config.items()):
params.append('{}={!r}'.format(k, v))
classname = type(self).__name__
r = '{}({})'.format(classname, ', '.join(params))
r = textwrap.fill(r, width=80, break_long_words=False, subsequent_indent=' ')
return r