# coding: utf-8
import json
import datetime
import numpy as np
from .generic_utils import str_strip
[docs]class PythonCharmersJSONEncoder(json.JSONEncoder):
""" Json encoder for Python data structures.
Supports the following objects and types by default (``json.JSONEncoder``):
+-------------------+---------------+
| Python | JSON |
+===================+===============+
| dict | object |
+-------------------+---------------+
| list, tuple | array |
+-------------------+---------------+
| str | string |
+-------------------+---------------+
| int, float | number |
+-------------------+---------------+
| True | true |
+-------------------+---------------+
| False | false |
+-------------------+---------------+
| None | null |
+-------------------+---------------+
"""
[docs] def default(self, obj):
""" Override this method to accommodate other types of data structures.
Currently, supports the following objects and types by overriding.
+-----------------------+---------------+
| Python | JSON |
+=======================+===============+
| np.integar | number(int) |
+-----------------------+---------------+
| np.float | number(float) |
+-----------------------+---------------+
| np.ndarray | array |
+-----------------------+---------------+
| np.random.RandomState | object |
+-----------------------+---------------+
| datetime.datetime | string |
+-----------------------+---------------+
"""
# Numpy object
if isinstance(obj, np.integer):
return int(obj)
elif isinstance(obj, np.floating):
return float(obj)
elif isinstance(obj, np.ndarray):
return obj.tolist()
elif isinstance(obj, np.random.RandomState):
dict_obj = dict(zip(
["MT19937", "unsigned_integer_keys", "pos", "has_gauss", "cached_gaussian"],
obj.get_state()
))
return dict_obj
# datetime object
elif isinstance(obj, datetime.datetime):
return obj.isoformat()
return super().default(obj)
[docs]def dumps_json(obj, ensure_ascii=False, indent=2, cls=PythonCharmersJSONEncoder, flatten_list=True, **kwargs):
"""dumps Json object to String.
Args:
obj (dict) : Serialize ``obj`` as a JSON formatted stream.
ensure_ascii (bool) : If ``ensure_ascii`` is false, then the strings written to ``fp`` can contain non-ASCII characters if they appear in strings contained in ``obj``.
indent (int) : If ``indent`` is a non-negative integer, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0 will only insert newlines. ``None`` is the most compact representation.
cls (json.JSONEncoder) : To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the ``.default()`` method to serialize additional types), specify it with the ``cls`` kwarg; otherwise ``PythonCharmersJSONEncoder`` is used.
flatten_list (bool) : Whether you want to flatten the list or not.
Example:
>>> import datetime
>>> from pycharmers.utils import dumps_json
>>> print(dumps_json(obj={
... "date": datetime.datetime.now(),
... "bool" : True,
... "dual_list": [[1,2,3],[4,5,6]]
>>> }))
{
"date": "2020-12-07T23:28:49.311962",
"bool": true,
"dual_list": [
[1, 2, 3],
[4, 5, 6]
]
}
"""
if flatten_list:
encoder = cls(ensure_ascii=ensure_ascii, indent=indent)
chunks=[]; num_brackets=0
for e in encoder.iterencode(obj, _one_shot=True):
if e[0]=="[": num_brackets+=1
elif e[0]=="]": num_brackets-=1
if num_brackets>1: e = str_strip(e)
chunks.append(e)
text = ''.join(chunks).replace("[ ", "[")
else:
text = json.dumps(obj=obj, ensure_ascii=ensure_ascii, indent=indent, cls=cls, **kwargs)
text = text.replace("NaN", "null")
return text
[docs]def save_json(obj, file, ensure_ascii=False, indent=2, cls=PythonCharmersJSONEncoder, flatten_list=True, **kwargs):
""" Save the json file with easy-to-use arguments
Args:
obj (dict) : Serialize ``obj`` as a JSON formatted stream.
file (str) : a text or byte string giving the path of the file to be opened.
ensure_ascii (bool) : If ``ensure_ascii`` is false, then the strings written to ``fp`` can contain non-ASCII characters if they appear in strings contained in ``obj``.
indent (int) : If ``indent`` is a non-negative integer, then JSON array elements and object members will be pretty-printed with that indent level. An indent level of 0 will only insert newlines. ``None`` is the most compact representation.
cls (json.JSONEncoder) : To use a custom ``JSONEncoder`` subclass (e.g. one that overrides the ``.default()`` method to serialize additional types), specify it with the ``cls`` kwarg; otherwise ``PythonCharmersJSONEncoder`` is used.
flatten_list (bool) : Whether you want to flatten the list or not.
Example:
>>> import datetime
>>> from pycharmers.utils import save_json
>>> save_json(obj={"date": datetime.datetime.now(), "bool" : True}, file="sample.json")
>>> with open("sample.json") as f:
>>> for line in f.readlines():
>>> print(line, end="")
{
"date": "2020-09-13T20:45:56.614838",
"bool": true
}
"""
text = dumps_json(
obj=obj,
ensure_ascii=ensure_ascii,
indent=indent,
cls=cls,
flatten_list=flatten_list,
**kwargs
)
with open(file=file, mode="w", encoding="utf-8") as fp:
fp.write(text)
