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@mbarkhau
Last active Feb 8, 2017
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pretty_json.py
# -*- coding: utf-8 -*-
"""Prettify JSON
Usage:
pjson --help
pjson --test
cat my.json | pjson
"""
from __future__ import division
from __future__ import print_function
from __future__ import absolute_import
from __future__ import unicode_literals
import sys
import json
import datetime as dt
import functools as ft
# TODO (mb 2016-09-14): preserve ordering of keys
PY2 = sys.version_info.major < 3
if PY2:
INT_TYPES = (int, long) # noqa
NUM_TYPES = (int, long, float) # noqa
BASIC_TYPES = (unicode, bytes, int, long, float, type(None)) # noqa
str = unicode # noqa
else:
INT_TYPES = (int,)
NUM_TYPES = (int, float)
BASIC_TYPES = (str, bytes, int, float, type(None))
str = str
def _get_alignment_fmt(values, val_strings, is_key=False):
fmt = "{}"
if all(isinstance(v, INT_TYPES) for v in values):
# align to the right
fmt = "{{:>{}}}".format(max(map(len, val_strings)))
use_raw_vals = True
elif all(isinstance(v, float) for v in values):
# align by decimal
fmt = "{{:{}.{}f}}".format(
max(map(len, val_strings)),
max((len(v.split(".")[-1]) for v in val_strings)),
)
if is_key:
fmt = '"{}"'.format(fmt)
use_raw_vals = True
elif all(isinstance(v, (str, bytes)) for v in values):
# align to the left
fmt = "{{:<{}}}".format(max(map(len, val_strings)))
use_raw_vals = False
else:
use_raw_vals = False
return fmt, use_raw_vals
def dumps(
data,
indent=4,
sort_keys=True,
max_elem_len=60,
align=True,
_depth=1,
sorted_key=None,
encoding='utf-8'):
_dumps = ft.partial(
dumps,
indent=indent,
sort_keys=sort_keys,
max_elem_len=max_elem_len,
align=align,
_depth=_depth + 1,
sorted_key=sorted_key,
encoding=encoding
)
if isinstance(data, bytes):
data = data.decode(encoding)
pad = indent * " "
if isinstance(data, (tuple, list)):
# decode all bytes values
data = [(v.decode(encoding) if isinstance(v, bytes) else v) for v in data]
sub_elems = [_dumps(v) for v in data]
total_len = 2 + len(sub_elems) * 2 + sum(map(len, sub_elems))
has_container_types = any(isinstance(v, (tuple, list, dict)) for v in data)
if total_len <= max_elem_len and not has_container_types:
joiner = ", "
prefix = "["
suffix = "]"
else:
joiner = ",\n" + _depth * pad
prefix = "[\n" + _depth * pad
suffix = "\n" + (_depth - 1) * pad + "]"
elif isinstance(data, dict):
# decode all bytes keys and values
dict_type = type(data)
try:
dec_data = dict_type()
except:
dec_data = data.copy()
dec_data.clear()
for k, v in data.items():
dec_key = k.decode(encoding) if isinstance(k, bytes) else k
dec_val = v.decode(encoding) if isinstance(v, bytes) else v
dec_data[dec_key] = dec_val
sub_items = {json.dumps(k): json.dumps(v) for k, v in data.items()}
keys_len = sum(map(len, sub_items.keys()))
vals_len = sum(map(len, sub_items.values()))
total_len = 2 + len(sub_items) * 4 + keys_len + vals_len
k_fmt = v_fmt = "{}"
use_raw_keys = False
use_raw_vals = False
if align and all(isinstance(k, BASIC_TYPES) for k in data.keys()):
k_fmt, use_raw_keys = _get_alignment_fmt(data.keys(), sub_items.keys(), is_key=True)
if total_len <= max_elem_len or len(sub_items) < 2:
joiner = ", "
prefix = "{"
suffix = "}"
if sort_keys:
keys = sorted(data.keys(), key=sorted_key)
else:
keys = list(data.keys())
sub_item_output = [
(json.dumps(k), _dumps(data[k], _depth=_depth))
for k in keys
]
else:
if align:
if all(isinstance(v, NUM_TYPES) for v in data.values()):
v_fmt, use_raw_vals = _get_alignment_fmt(data.values(), sub_items.values())
else:
k_fmt = v_fmt = "{}"
joiner = ",\n" + _depth * pad
prefix = "{\n" + _depth * pad
suffix = "\n" + (_depth - 1) * pad + "}"
if sort_keys:
keys = sorted(data, key=sorted_key)
else:
keys = data.keys()
sub_item_output = [
(
(k if use_raw_keys else json.dumps(k)),
(data[k] if use_raw_vals else _dumps(data[k])),
)
for k in keys
]
kv_fmt = k_fmt + ": " + v_fmt
sub_elems = [kv_fmt.format(*k_v) for k_v in sub_item_output]
elif isinstance(data, (dt.datetime, dt.date)):
return '"' + data.isoformat() + '"'
elif isinstance(data, BASIC_TYPES):
return json.dumps(data)
else:
raise TypeError("'{}' is not a searializable type.".format(type(data)))
return prefix + joiner.join(sub_elems) + suffix
loads = json.loads
def main(args):
if '--help' in args:
print(__doc__)
return 0
kwargs = dict(
kv.lstrip("-").replace("-", "_").split("=")
for kv in args if "=" in kv
)
for k, v in list(kwargs.items()):
if v.isdigit():
kwargs[k] = int(v)
in_data_raw = sys.stdin.read()
if in_data_raw:
in_data = loads(in_data_raw)
print(dumps(in_data, **kwargs))
return 0
if __name__ == '__main__':
sys.exit(main(sys.argv[1:]))
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