我有一个基本的字典如下:
sample = {}
sample['title'] = "String"
sample['somedate'] = somedatetimehere
当我尝试做jsonify(sample)时，我得到:
TypeError: datetime.datetime(2012, 8, 8, 21, 46, 24, 862000) is not JSON serializable
我该怎么做才能使我的字典样本克服上面的错误呢?
注意:虽然它可能不相关，字典是从mongodb的记录检索中生成的，当我打印出str(sample['somedate'])时，输出是2012-08-08 21:46:24.862000。
当前回答
将日期转换为字符串
sample['somedate'] = str( datetime.utcnow() )
其他回答
最简单的方法是将字典中datetime格式的部分更改为isoformat。这个值实际上是一个isoformat的字符串，json可以接受。
v_dict = version.dict()
v_dict['created_at'] = v_dict['created_at'].isoformat()
试着用一个例子来解析它:
#!/usr/bin/env python
import datetime
import json
import dateutil.parser # pip install python-dateutil
class JSONEncoder(json.JSONEncoder):
def default(self, obj):
if isinstance(obj, datetime.datetime):
return obj.isoformat()
return super(JSONEncoder, self).default(obj)
def test():
dts = [
datetime.datetime.now(),
datetime.datetime.now(datetime.timezone(-datetime.timedelta(hours=4))),
datetime.datetime.utcnow(),
datetime.datetime.now(datetime.timezone.utc),
]
for dt in dts:
dt_isoformat = json.loads(json.dumps(dt, cls=JSONEncoder))
dt_parsed = dateutil.parser.parse(dt_isoformat)
assert dt == dt_parsed
print(f'{dt}, {dt_isoformat}, {dt_parsed}')
# 2018-07-22 02:22:42.910637, 2018-07-22T02:22:42.910637, 2018-07-22 02:22:42.910637
# 2018-07-22 02:22:42.910643-04:00, 2018-07-22T02:22:42.910643-04:00, 2018-07-22 02:22:42.910643-04:00
# 2018-07-22 06:22:42.910645, 2018-07-22T06:22:42.910645, 2018-07-22 06:22:42.910645
# 2018-07-22 06:22:42.910646+00:00, 2018-07-22T06:22:42.910646+00:00, 2018-07-22 06:22:42.910646+00:00
if __name__ == '__main__':
test()
将日期转换为字符串
sample['somedate'] = str( datetime.utcnow() )
根据@jjmontes的回答，我使用了以下方法。 适用于flask和flask-rest用户
# get json string
jsonStr = json.dumps(my_dictionary, indent=1, sort_keys=True, default=str)
# then covert json string to json object
return json.loads(jsonStr)
在其他答案的基础上，一个简单的解决方案基于只转换datetime的特定序列化器。Datetime和Datetime。将对象日期指定为字符串。
from datetime import date, datetime
def json_serial(obj):
"""JSON serializer for objects not serializable by default json code"""
if isinstance(obj, (datetime, date)):
return obj.isoformat()
raise TypeError ("Type %s not serializable" % type(obj))
As seen, the code just checks to find out if object is of class datetime.datetime or datetime.date, and then uses .isoformat() to produce a serialized version of it, according to ISO 8601 format, YYYY-MM-DDTHH:MM:SS (which is easily decoded by JavaScript). If more complex serialized representations are sought, other code could be used instead of str() (see other answers to this question for examples). The code ends by raising an exception, to deal with the case it is called with a non-serializable type.
这个json_serial函数可以这样使用:
from datetime import datetime
from json import dumps
print dumps(datetime.now(), default=json_serial)
详细说明如何将默认参数设置为json。可以在json模块文档的基本用法章节中找到dump作品。
