Source code for numcodecs.json

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): buf = np.asarray(buf) items = 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]) 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