标签归档：json

json和simplejson Python模块之间有什么区别？

2021年7月27日 Python实用宝典

问题：json和simplejson Python模块之间有什么区别？

我已经看到许多项目使用simplejson模块而不是json标准库中的模块。另外，有许多不同的simplejson模块。为什么要使用这些替代方法而不是标准库中的替代方法？

I have seen many projects using simplejson module instead of json module from the Standard Library. Also, there are many different simplejson modules. Why would use these alternatives, instead of the one in the Standard Library?

回答 0

json 是 simplejson，已添加到stdlib中。但是自从json2.6中添加以来，它simplejson具有在更多Python版本（2.4+）上工作的优势。

simplejson的更新频率也比Python高，因此，如果您需要（或想要）最新版本simplejson，则尽可能使用它自己。

我认为，一种好的做法是将其中一个作为后备。

try:
    import simplejson as json
except ImportError:
    import json

json is simplejson, added to the stdlib. But since json was added in 2.6, simplejson has the advantage of working on more Python versions (2.4+).

simplejson is also updated more frequently than Python, so if you need (or want) the latest version, it’s best to use simplejson itself, if possible.

A good practice, in my opinion, is to use one or the other as a fallback.

try:
    import simplejson as json
except ImportError:
    import json

回答 1

我必须不同意其他答案：内置json库（在Python 2.7中）不一定比慢simplejson。它也没有这个烦人的unicode错误。

这是一个简单的基准：

import json
import simplejson
from timeit import repeat

NUMBER = 100000
REPEAT = 10

def compare_json_and_simplejson(data):
    """Compare json and simplejson - dumps and loads"""
    compare_json_and_simplejson.data = data
    compare_json_and_simplejson.dump = json.dumps(data)
    assert json.dumps(data) == simplejson.dumps(data)
    result = min(repeat("json.dumps(compare_json_and_simplejson.data)", "from __main__ import json, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "      json dumps {} seconds".format(result)
    result = min(repeat("simplejson.dumps(compare_json_and_simplejson.data)", "from __main__ import simplejson, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "simplejson dumps {} seconds".format(result)
    assert json.loads(compare_json_and_simplejson.dump) == data
    result = min(repeat("json.loads(compare_json_and_simplejson.dump)", "from __main__ import json, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "      json loads {} seconds".format(result)
    result = min(repeat("simplejson.loads(compare_json_and_simplejson.dump)", "from __main__ import simplejson, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "simplejson loads {} seconds".format(result)


print "Complex real world data:" 
COMPLEX_DATA = {'status': 1, 'timestamp': 1362323499.23, 'site_code': 'testing123', 'remote_address': '212.179.220.18', 'input_text': u'ny monday for less than \u20aa123', 'locale_value': 'UK', 'eva_version': 'v1.0.3286', 'message': 'Successful Parse', 'muuid1': '11e2-8414-a5e9e0fd-95a6-12313913cc26', 'api_reply': {"api_reply": {"Money": {"Currency": "ILS", "Amount": "123", "Restriction": "Less"}, "ProcessedText": "ny monday for less than \\u20aa123", "Locations": [{"Index": 0, "Derived From": "Default", "Home": "Default", "Departure": {"Date": "2013-03-04"}, "Next": 10}, {"Arrival": {"Date": "2013-03-04", "Calculated": True}, "Index": 10, "All Airports Code": "NYC", "Airports": "EWR,JFK,LGA,PHL", "Name": "New York City, New York, United States (GID=5128581)", "Latitude": 40.71427, "Country": "US", "Type": "City", "Geoid": 5128581, "Longitude": -74.00597}]}}}
compare_json_and_simplejson(COMPLEX_DATA)
print "\nSimple data:"
SIMPLE_DATA = [1, 2, 3, "asasd", {'a':'b'}]
compare_json_and_simplejson(SIMPLE_DATA)

以及在我的系统（Python 2.7.4，Linux 64位）上的结果：

复杂的现实世界数据：
json转储1.56666707993秒
simplejson转储2.25638604164秒
json加载2.71256899834秒
simplejson加载1.29233884811秒

简单数据：
json转储0.370109081268秒
simplejson转储0.574181079865秒
json加载0.422876119614秒
simplejson加载0.270955085754秒

对于转储，json比快simplejson。对于加载，simplejson速度更快。

由于我当前正在构建Web服务，dumps()因此更为重要-并且始终首选使用标准库。

另外，cjson在过去的4年中没有更新，因此我不会去碰它。

I have to disagree with the other answers: the built in json library (in Python 2.7) is not necessarily slower than simplejson. It also doesn’t have this annoying unicode bug.

Here is a simple benchmark:

import json
import simplejson
from timeit import repeat

NUMBER = 100000
REPEAT = 10

def compare_json_and_simplejson(data):
    """Compare json and simplejson - dumps and loads"""
    compare_json_and_simplejson.data = data
    compare_json_and_simplejson.dump = json.dumps(data)
    assert json.dumps(data) == simplejson.dumps(data)
    result = min(repeat("json.dumps(compare_json_and_simplejson.data)", "from __main__ import json, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "      json dumps {} seconds".format(result)
    result = min(repeat("simplejson.dumps(compare_json_and_simplejson.data)", "from __main__ import simplejson, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "simplejson dumps {} seconds".format(result)
    assert json.loads(compare_json_and_simplejson.dump) == data
    result = min(repeat("json.loads(compare_json_and_simplejson.dump)", "from __main__ import json, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "      json loads {} seconds".format(result)
    result = min(repeat("simplejson.loads(compare_json_and_simplejson.dump)", "from __main__ import simplejson, compare_json_and_simplejson", 
                 repeat = REPEAT, number = NUMBER))
    print "simplejson loads {} seconds".format(result)


print "Complex real world data:" 
COMPLEX_DATA = {'status': 1, 'timestamp': 1362323499.23, 'site_code': 'testing123', 'remote_address': '212.179.220.18', 'input_text': u'ny monday for less than \u20aa123', 'locale_value': 'UK', 'eva_version': 'v1.0.3286', 'message': 'Successful Parse', 'muuid1': '11e2-8414-a5e9e0fd-95a6-12313913cc26', 'api_reply': {"api_reply": {"Money": {"Currency": "ILS", "Amount": "123", "Restriction": "Less"}, "ProcessedText": "ny monday for less than \\u20aa123", "Locations": [{"Index": 0, "Derived From": "Default", "Home": "Default", "Departure": {"Date": "2013-03-04"}, "Next": 10}, {"Arrival": {"Date": "2013-03-04", "Calculated": True}, "Index": 10, "All Airports Code": "NYC", "Airports": "EWR,JFK,LGA,PHL", "Name": "New York City, New York, United States (GID=5128581)", "Latitude": 40.71427, "Country": "US", "Type": "City", "Geoid": 5128581, "Longitude": -74.00597}]}}}
compare_json_and_simplejson(COMPLEX_DATA)
print "\nSimple data:"
SIMPLE_DATA = [1, 2, 3, "asasd", {'a':'b'}]
compare_json_and_simplejson(SIMPLE_DATA)

And the results on my system (Python 2.7.4, Linux 64-bit):

Complex real world data:
json dumps 1.56666707993 seconds
simplejson dumps 2.25638604164 seconds
json loads 2.71256899834 seconds
simplejson loads 1.29233884811 seconds

Simple data:
json dumps 0.370109081268 seconds
simplejson dumps 0.574181079865 seconds
json loads 0.422876119614 seconds
simplejson loads 0.270955085754 seconds

For dumping, json is faster than simplejson. For loading, simplejson is faster.

Since I am currently building a web service, dumps() is more important—and using a standard library is always preferred.

Also, cjson was not updated in the past 4 years, so I wouldn’t touch it.

回答 2

所有这些答案都不太有用，因为它们对时间敏感。

对我自己进行一些研究后，我发现simplejson，如果将其更新为最新版本，确实比内置速度更快。

pip/easy_install我想在ubuntu 12.04上安装2.3.2，但是在发现最新simplejson版本实际上是3.3.0之后，我更新了它并重新进行了时间测试。

simplejson比json负载下的内置速度快3倍
simplejson比json转储时的内置速度快30％

免责声明：

上面的语句在python-2.7.3和simplejson 3.3.0中（使用c speedups），并且要确保我的回答也不是时间敏感的，您应该运行自己的测试以进行检查，因为版本之间的差异很大；没有时间敏感的简单答案。

如何判断是否在simplejson中启用了C加速：

import simplejson
# If this is True, then c speedups are enabled.
print bool(getattr(simplejson, '_speedups', False))

更新：我最近遇到了一个名为ujson的库，它比simplejson某些基本测试的执行速度快约3倍。

All of these answers aren’t very helpful because they are time sensitive.

After doing some research of my own I found that simplejson is indeed faster than the builtin, if you keep it updated to the latest version.

pip/easy_install wanted to install 2.3.2 on ubuntu 12.04, but after finding out the latest simplejson version is actually 3.3.0, so I updated it and reran the time tests.

simplejson is about 3x faster than the builtin json at loads
simplejson is about 30% faster than the builtin json at dumps

Disclaimer:

The above statements are in python-2.7.3 and simplejson 3.3.0 (with c speedups) And to make sure my answer also isn’t time sensitive, you should run your own tests to check since it varies so much between versions; there’s no easy answer that isn’t time sensitive.

How to tell if C speedups are enabled in simplejson:

import simplejson
# If this is True, then c speedups are enabled.
print bool(getattr(simplejson, '_speedups', False))

UPDATE: I recently came across a library called ujson that is performing ~3x faster than simplejson with some basic tests.

回答 3

我一直在对json，simplejson和cjson进行基准测试。

cjson最快
simplejson与cjson差不多
json比simplejson慢10倍

http://pastie.org/1507411：

$ python test_serialization_speed.py 
--------------------
   Encoding Tests
--------------------
Encoding: 100000 x {'m': 'asdsasdqwqw', 't': 3}
[      json] 1.12385 seconds for 100000 runs. avg: 0.011239ms
[simplejson] 0.44356 seconds for 100000 runs. avg: 0.004436ms
[     cjson] 0.09593 seconds for 100000 runs. avg: 0.000959ms

Encoding: 10000 x {'m': [['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19]], 't': 3}
[      json] 7.76628 seconds for 10000 runs. avg: 0.776628ms
[simplejson] 0.51179 seconds for 10000 runs. avg: 0.051179ms
[     cjson] 0.44362 seconds for 10000 runs. avg: 0.044362ms

--------------------
   Decoding Tests
--------------------
Decoding: 100000 x {"m": "asdsasdqwqw", "t": 3}
[      json] 3.32861 seconds for 100000 runs. avg: 0.033286ms
[simplejson] 0.37164 seconds for 100000 runs. avg: 0.003716ms
[     cjson] 0.03893 seconds for 100000 runs. avg: 0.000389ms

Decoding: 10000 x {"m": [["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19]], "t": 3}
[      json] 37.26270 seconds for 10000 runs. avg: 3.726270ms
[simplejson] 0.56643 seconds for 10000 runs. avg: 0.056643ms
[     cjson] 0.33007 seconds for 10000 runs. avg: 0.033007ms

I’ve been benchmarking json, simplejson and cjson.

cjson is fastest
simplejson is almost on par with cjson
json is about 10x slower than simplejson

http://pastie.org/1507411:

$ python test_serialization_speed.py 
--------------------
   Encoding Tests
--------------------
Encoding: 100000 x {'m': 'asdsasdqwqw', 't': 3}
[      json] 1.12385 seconds for 100000 runs. avg: 0.011239ms
[simplejson] 0.44356 seconds for 100000 runs. avg: 0.004436ms
[     cjson] 0.09593 seconds for 100000 runs. avg: 0.000959ms

Encoding: 10000 x {'m': [['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19], ['0', 1, '2', 3, '4', 5, '6', 7, '8', 9, '10', 11, '12', 13, '14', 15, '16', 17, '18', 19]], 't': 3}
[      json] 7.76628 seconds for 10000 runs. avg: 0.776628ms
[simplejson] 0.51179 seconds for 10000 runs. avg: 0.051179ms
[     cjson] 0.44362 seconds for 10000 runs. avg: 0.044362ms

--------------------
   Decoding Tests
--------------------
Decoding: 100000 x {"m": "asdsasdqwqw", "t": 3}
[      json] 3.32861 seconds for 100000 runs. avg: 0.033286ms
[simplejson] 0.37164 seconds for 100000 runs. avg: 0.003716ms
[     cjson] 0.03893 seconds for 100000 runs. avg: 0.000389ms

Decoding: 10000 x {"m": [["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19], ["0", 1, "2", 3, "4", 5, "6", 7, "8", 9, "10", 11, "12", 13, "14", 15, "16", 17, "18", 19]], "t": 3}
[      json] 37.26270 seconds for 10000 runs. avg: 3.726270ms
[simplejson] 0.56643 seconds for 10000 runs. avg: 0.056643ms
[     cjson] 0.33007 seconds for 10000 runs. avg: 0.033007ms

回答 4

一些值在simplejson和json之间序列化的方式有所不同。

值得注意的是，的实例由collections.namedtuple序列化为数组，json但由序列化为对象simplejson。您可以通过传递namedtuple_as_object=False给来覆盖此行为simplejson.dump，但是默认情况下行为不匹配。

>>> import collections, simplejson, json
>>> TupleClass = collections.namedtuple("TupleClass", ("a", "b"))
>>> value = TupleClass(1, 2)
>>> json.dumps(value)
'[1, 2]'
>>> simplejson.dumps(value)
'{"a": 1, "b": 2}'
>>> simplejson.dumps(value, namedtuple_as_object=False)
'[1, 2]'

Some values are serialized differently between simplejson and json.

Notably, instances of collections.namedtuple are serialized as arrays by json but as objects by simplejson. You can override this behaviour by passing namedtuple_as_object=False to simplejson.dump, but by default the behaviours do not match.

>>> import collections, simplejson, json
>>> TupleClass = collections.namedtuple("TupleClass", ("a", "b"))
>>> value = TupleClass(1, 2)
>>> json.dumps(value)
'[1, 2]'
>>> simplejson.dumps(value)
'{"a": 1, "b": 2}'
>>> simplejson.dumps(value, namedtuple_as_object=False)
'[1, 2]'

回答 5

我发现与Python 2.7和simplejson 3.3.1的API不兼容之处在于输出是生成str对象还是unicode对象。例如

>>> from json import JSONDecoder
>>> jd = JSONDecoder()
>>> jd.decode("""{ "a":"b" }""")
{u'a': u'b'}

与

>>> from simplejson import JSONDecoder
>>> jd = JSONDecoder()
>>> jd.decode("""{ "a":"b" }""")
{'a': 'b'}

如果首选项是使用simplejson，则可以通过将参数字符串强制为unicode来解决此问题，如下所示：

>>> from simplejson import JSONDecoder
>>> jd = JSONDecoder()
>>> jd.decode(unicode("""{ "a":"b" }""", "utf-8"))
{u'a': u'b'}

强制确实需要知道原始字符集，例如：

>>> jd.decode(unicode("""{ "a": "ξηθννββωφρες" }"""))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xce in position 8: ordinal not in range(128)

这是无法解决的问题40

An API incompatibility I found, with Python 2.7 vs simplejson 3.3.1 is in whether output produces str or unicode objects. e.g.

>>> from json import JSONDecoder
>>> jd = JSONDecoder()
>>> jd.decode("""{ "a":"b" }""")
{u'a': u'b'}

>>> from simplejson import JSONDecoder
>>> jd = JSONDecoder()
>>> jd.decode("""{ "a":"b" }""")
{'a': 'b'}

If the preference is to use simplejson, then this can be addressed by coercing the argument string to unicode, as in:

>>> from simplejson import JSONDecoder
>>> jd = JSONDecoder()
>>> jd.decode(unicode("""{ "a":"b" }""", "utf-8"))
{u'a': u'b'}

The coercion does require knowing the original charset, for example:

>>> jd.decode(unicode("""{ "a": "ξηθννββωφρες" }"""))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xce in position 8: ordinal not in range(128)

This is the won’t fix issue 40

回答 6

项目使用simplejson的另一个原因是内置的json最初不包括其C加速，因此性能差异非常明显。

Another reason projects use simplejson is that the builtin json did not originally include its C speedups, so the performance difference was noticeable.

回答 7

内置json模块已包含在Python 2.6中。任何支持Python <2.6以下版本的项目都必须具有后备功能。在许多情况下，这种后备状态为simplejson。

The builtin json module got included in Python 2.6. Any projects that support versions of Python < 2.6 need to have a fallback. In many cases, that fallback is simplejson.

回答 8

这是Python json库的（现在已经过时）比较：

比较Python的JSON模块（存档链接）

无论比较结果如何，如果您使用的是Python 2.6，都应使用标准库json。并且..不然也可以使用simplejson。

Here’s (a now outdated) comparison of Python json libraries:

Comparing JSON modules for Python (archive link)

Regardless of the results in this comparison you should use the standard library json if you are on Python 2.6. And.. might as well just use simplejson otherwise.

回答 9

simplejson模块仅比json快1.5倍（在我的计算机上，使用simplejson 2.1.1和Python 2.7 x86）。

如果需要，可以尝试进行基准测试：http : //abral.altervista.org/jsonpickle-bench.zip 在我的PC上，simplejson比cPickle更快。我也想知道您的基准！

就像Coady所说的，simplejson和json之间的区别可能是simplejson包含_speedups.c。那么，为什么python开发人员不使用simplejson？

simplejson module is simply 1,5 times faster than json (On my computer, with simplejson 2.1.1 and Python 2.7 x86).

If you want, you can try the benchmark: http://abral.altervista.org/jsonpickle-bench.zip On my PC simplejson is faster than cPickle. I would like to know also your benchmarks!

Probably, as said Coady, the difference between simplejson and json is that simplejson includes _speedups.c. So, why don’t python developers use simplejson?

回答 10

在python3，如果你的字符串b'bytes'，与json你有.decode()内容，然后才能加载它。 simplejson照顾好这个，所以你可以做simplejson.loads(byte_string)。

In python3, if you a string of b'bytes', with json you have to .decode() the content before you can load it. simplejson takes care of this so you can just do simplejson.loads(byte_string).

回答 11

json 似乎比 simplejson最新版本的加载和转储

测试版本：

的Python：3.6.8
json：2.0.9
simplejson：3.16.0

结果：

>>> def test(obj, call, data, times):
...   s = datetime.now()
...   print("calling: ", call, " in ", obj, " ", times, " times") 
...   for _ in range(times):
...     r = getattr(obj, call)(data)
...   e = datetime.now()
...   print("total time: ", str(e-s))
...   return r

>>> test(json, "dumps", data, 10000)
calling:  dumps  in  <module 'json' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\json\\__init__.py'>   10000  times
total time:  0:00:00.054857

>>> test(simplejson, "dumps", data, 10000)
calling:  dumps  in  <module 'simplejson' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\site-packages\\simplejson\\__init__.py'>   10000  times
total time:  0:00:00.419895
'{"1": 100, "2": "acs", "3.5": 3.5567, "d": [1, "23"], "e": {"a": "A"}}'

>>> test(json, "loads", strdata, 1000)
calling:  loads  in  <module 'json' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\json\\__init__.py'>   1000  times
total time:  0:00:00.004985
{'1': 100, '2': 'acs', '3.5': 3.5567, 'd': [1, '23'], 'e': {'a': 'A'}}

>>> test(simplejson, "loads", strdata, 1000)
calling:  loads  in  <module 'simplejson' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\site-packages\\simplejson\\__init__.py'>   1000  times
total time:  0:00:00.040890
{'1': 100, '2': 'acs', '3.5': 3.5567, 'd': [1, '23'], 'e': {'a': 'A'}}

对于版本：

的Python：3.7.4
json：2.0.9
simplejson：3.17.0

json在转储操作期间比simplejson快，但在加载操作期间两者保持相同的速度

json seems faster than simplejson in both cases of loads and dumps in latest version

Tested versions:

python: 3.6.8
json: 2.0.9
simplejson: 3.16.0

Results:

>>> def test(obj, call, data, times):
...   s = datetime.now()
...   print("calling: ", call, " in ", obj, " ", times, " times") 
...   for _ in range(times):
...     r = getattr(obj, call)(data)
...   e = datetime.now()
...   print("total time: ", str(e-s))
...   return r

>>> test(json, "dumps", data, 10000)
calling:  dumps  in  <module 'json' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\json\\__init__.py'>   10000  times
total time:  0:00:00.054857

>>> test(simplejson, "dumps", data, 10000)
calling:  dumps  in  <module 'simplejson' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\site-packages\\simplejson\\__init__.py'>   10000  times
total time:  0:00:00.419895
'{"1": 100, "2": "acs", "3.5": 3.5567, "d": [1, "23"], "e": {"a": "A"}}'

>>> test(json, "loads", strdata, 1000)
calling:  loads  in  <module 'json' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\json\\__init__.py'>   1000  times
total time:  0:00:00.004985
{'1': 100, '2': 'acs', '3.5': 3.5567, 'd': [1, '23'], 'e': {'a': 'A'}}

>>> test(simplejson, "loads", strdata, 1000)
calling:  loads  in  <module 'simplejson' from 'C:\\Users\\jophine.antony\\AppData\\Local\\Programs\\Python\\Python36-32\\lib\\site-packages\\simplejson\\__init__.py'>   1000  times
total time:  0:00:00.040890
{'1': 100, '2': 'acs', '3.5': 3.5567, 'd': [1, '23'], 'e': {'a': 'A'}}

For versions:

python: 3.7.4
json: 2.0.9
simplejson: 3.17.0

json was faster than simplejson during dumps operation but both maintained the same speed during loads operations

回答 12

我在寻找要为Python 2.6安装simplejson时遇到了这个问题。我需要使用json.load（）的’object_pairs_hook’来将json文件加载为OrderedDict。熟悉最新版本的Python时，我没有意识到Python 2.6的json模块不包含’object_pairs_hook’，因此我为此目的必须安装simplejson。从个人经验来看，这就是为什么我使用simplejson而不是标准json模块的原因。

I came across this question as I was looking to install simplejson for Python 2.6. I needed to use the ‘object_pairs_hook’ of json.load() in order to load a json file as an OrderedDict. Being familiar with more recent versions of Python I didn’t realize that the json module for Python 2.6 doesn’t include the ‘object_pairs_hook’ so I had to install simplejson for this purpose. From personal experience this is why i use simplejson as opposed to the standard json module.

知识问答

将字典转换为JSON

2021年7月27日 Python实用宝典

问题：将字典转换为JSON

r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
file.write(str(r['rating']))

我无法访问JSON中的数据。我究竟做错了什么？

TypeError: string indices must be integers, not str

r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
file.write(str(r['rating']))

I am not able to access my data in the JSON. What am I doing wrong?

TypeError: string indices must be integers, not str

回答 0

json.dumps()将字典转换为str对象，而不是json(dict)对象！因此，您必须使用方法将其加载str到dictjson.loads()

请参阅json.dumps()作为保存方法和json.loads()检索方法。

这是代码示例，可以帮助您进一步了解它：

import json

r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
loaded_r = json.loads(r)
loaded_r['rating'] #Output 3.5
type(r) #Output str
type(loaded_r) #Output dict

json.dumps() converts a dictionary to str object, not a json(dict) object! So you have to load your str into a dict to use it by using json.loads() method

See json.dumps() as a save method and json.loads() as a retrieve method.

This is the code sample which might help you understand it more:

import json

r = {'is_claimed': 'True', 'rating': 3.5}
r = json.dumps(r)
loaded_r = json.loads(r)
loaded_r['rating'] #Output 3.5
type(r) #Output str
type(loaded_r) #Output dict

回答 1

json.dumps()返回python字典的JSON字符串表示形式。查看文件

您不能这样做，r['rating']因为r是字符串，不再是dict

也许你的意思是

r = {'is_claimed': 'True', 'rating': 3.5}
json = json.dumps(r) # note i gave it a different name
file.write(str(r['rating']))

json.dumps() returns the JSON string representation of the python dict. See the docs

You can’t do r['rating'] because r is a string, not a dict anymore

Perhaps you meant something like

r = {'is_claimed': 'True', 'rating': 3.5}
json = json.dumps(r) # note i gave it a different name
file.write(str(r['rating']))

回答 2

无需通过使用将其转换为字符串 json.dumps()

r = {'is_claimed': 'True', 'rating': 3.5}
file.write(r['is_claimed'])
file.write(str(r['rating']))

您可以直接从dict对象获取值。

No need to convert it in a string by using json.dumps()

r = {'is_claimed': 'True', 'rating': 3.5}
file.write(r['is_claimed'])
file.write(str(r['rating']))

You can get the values directly from the dict object.

回答 3

将r定义为字典应该可以解决这个问题：

>>> r: dict = {'is_claimed': 'True', 'rating': 3.5}
>>> print(r['rating'])
3.5
>>> type(r)
<class 'dict'>

Defining r as a dictionary should do the trick:

>>> r: dict = {'is_claimed': 'True', 'rating': 3.5}
>>> print(r['rating'])
3.5
>>> type(r)
<class 'dict'>

知识问答

如何在Flask中获取POST JSON？

2021年7月27日 Python实用宝典

问题：如何在Flask中获取POST JSON？

我正在尝试使用Flask构建一个简单的API，现在我想在其中读取一些POSTed JSON。我使用Postman Chrome扩展程序执行POST，而我发布的JSON就是{"text":"lalala"}。我尝试使用以下方法读取JSON：

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content
    return uuid

在浏览器上，它可以正确返回我放入GET中的UUID，但是在控制台上，它只是打印出来None（我希望它可以在其中打印出来{"text":"lalala"}。有人知道我如何从Flask方法中获取发布的JSON吗？

I’m trying to build a simple API using Flask, in which I now want to read some POSTed JSON. I do the POST with the Postman Chrome extension, and the JSON I POST is simply {"text":"lalala"}. I try to read the JSON using the following method:

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content
    return uuid

On the browser it correctly returns the UUID I put in the GET, but on the console, it just prints out None (where I expect it to print out the {"text":"lalala"}. Does anybody know how I can get the posted JSON from within the Flask method?

回答 0

首先，该.json属性是一个委托给request.get_json()method的属性，该属性记录了为什么None在此处看到。

您需要将请求内容类型设置为，application/json以使.json属性和.get_json()方法（不带参数）起作用，None否则两者都会产生这种情况。请参阅Flask Request文档：

如果mimetype表示JSON（包含application / json，请参见is_json()），则它将包含已解析的JSON数据，否则为None。

您可以request.get_json()通过向其传递force=True关键字参数来告知跳过内容类型要求。

请注意，如果此时引发异常（可能导致400 Bad Request响应），则您的JSON 数据无效。它在某种程度上畸形；您可能需要使用JSON验证程序进行检查。

First of all, the .json attribute is a property that delegates to the request.get_json() method, which documents why you see None here.

You need to set the request content type to application/json for the .json property and .get_json() method (with no arguments) to work as either will produce None otherwise. See the Flask Request documentation:

This will contain the parsed JSON data if the mimetype indicates JSON (application/json, see is_json()), otherwise it will be None.

You can tell request.get_json() to skip the content type requirement by passing it the force=True keyword argument.

Note that if an exception is raised at this point (possibly resulting in a 400 Bad Request response), your JSON data is invalid. It is in some way malformed; you may want to check it with a JSON validator.

回答 1

作为参考，以下是有关如何从Python客户端发送json的完整代码：

import requests
res = requests.post('http://localhost:5000/api/add_message/1234', json={"mytext":"lalala"})
if res.ok:
    print res.json()

“ json =“输入将自动设置内容类型，如下所述：使用Python请求发布JSON

以上客户端将使用此服务器端代码：

from flask import Flask, request, jsonify
app = Flask(__name__)

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content['mytext']
    return jsonify({"uuid":uuid})

if __name__ == '__main__':
    app.run(host= '0.0.0.0',debug=True)

For reference, here’s complete code for how to send json from a Python client:

import requests
res = requests.post('http://localhost:5000/api/add_message/1234', json={"mytext":"lalala"})
if res.ok:
    print res.json()

The “json=” input will automatically set the content-type, as discussed here: Post JSON using Python Requests

And the above client will work with this server-side code:

from flask import Flask, request, jsonify
app = Flask(__name__)

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content['mytext']
    return jsonify({"uuid":uuid})

if __name__ == '__main__':
    app.run(host= '0.0.0.0',debug=True)

回答 2

这就是我要做的方法，应该是

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.get_json(silent=True)
    # print(content) # Do your processing
    return uuid

随着silent=True集，该get_json功能将尝试检索JSON的身体的时候默默的失败。默认情况下，此设置为False。如果您始终希望使用json正文（而不是可选），请将其保留为silent=False。

设置force=True将忽略request.headers.get('Content-Type') == 'application/json'烧瓶对您的检查。默认情况下，它也设置为False。

请参见烧瓶文档。

我强烈建议您离开force=False并让客户端发送Content-Type标头以使其更加明确。

希望这可以帮助！

This is the way I would do it and it should be

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.get_json(silent=True)
    # print(content) # Do your processing
    return uuid

With silent=True set, the get_json function will fail silently when trying to retrieve the json body. By default this is set to False. If you are always expecting a json body (not optionally), leave it as silent=False.

Setting force=True will ignore the request.headers.get('Content-Type') == 'application/json' check that flask does for you. By default this is also set to False.

See flask documentation.

I would strongly recommend leaving force=False and make the client send the Content-Type header to make it more explicit.

Hope this helps!

回答 3

假设您已发布具有application/json内容类型的有效JSON ，request.json将具有已解析的JSON数据。

from flask import Flask, request, jsonify

app = Flask(__name__)


@app.route('/echo', methods=['POST'])
def hello():
   return jsonify(request.json)

Assuming you’ve posted valid JSON with the application/json content type, request.json will have the parsed JSON data.

from flask import Flask, request, jsonify

app = Flask(__name__)


@app.route('/echo', methods=['POST'])
def hello():
   return jsonify(request.json)

回答 4

对于所有问题都是来自ajax调用的人，这里有一个完整的示例：

Ajax调用：这里的关键是使用a dict然后JSON.stringify

    var dict = {username : "username" , password:"password"};

    $.ajax({
        type: "POST", 
        url: "http://127.0.0.1:5000/", //localhost Flask
        data : JSON.stringify(dict),
        contentType: "application/json",
    });

在服务器端：

from flask import Flask
from flask import request
import json

app = Flask(__name__)

@app.route("/",  methods = ['POST'])
def hello():
    print(request.get_json())
    return json.dumps({'success':True}), 200, {'ContentType':'application/json'} 

if __name__ == "__main__":
    app.run()

For all those whose issue was from the ajax call, here is a full example :

Ajax call : the key here is to use a dict and then JSON.stringify

    var dict = {username : "username" , password:"password"};

    $.ajax({
        type: "POST", 
        url: "http://127.0.0.1:5000/", //localhost Flask
        data : JSON.stringify(dict),
        contentType: "application/json",
    });

And on server side :

from flask import Flask
from flask import request
import json

app = Flask(__name__)

@app.route("/",  methods = ['POST'])
def hello():
    print(request.get_json())
    return json.dumps({'success':True}), 200, {'ContentType':'application/json'} 

if __name__ == "__main__":
    app.run()

回答 5

给出另一种方法。

from flask import Flask, jsonify, request
app = Flask(__name__)

@app.route('/service', methods=['POST'])
def service():
    data = json.loads(request.data)
    text = data.get("text",None)
    if text is None:
        return jsonify({"message":"text not found"})
    else:
        return jsonify(data)

if __name__ == '__main__':
    app.run(host= '0.0.0.0',debug=True)

To give another approach.

from flask import Flask, jsonify, request
app = Flask(__name__)

@app.route('/service', methods=['POST'])
def service():
    data = json.loads(request.data)
    text = data.get("text",None)
    if text is None:
        return jsonify({"message":"text not found"})
    else:
        return jsonify(data)

if __name__ == '__main__':
    app.run(host= '0.0.0.0',debug=True)

回答 6

假设您发布了有效的JSON，

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content['uuid']
    # Return data as JSON
    return jsonify(content)

Assuming that you have posted valid JSON,

@app.route('/api/add_message/<uuid>', methods=['GET', 'POST'])
def add_message(uuid):
    content = request.json
    print content['uuid']
    # Return data as JSON
    return jsonify(content)

回答 7

尝试使用力参数…

request.get_json(force = True)

Try to use force parameter…

request.get_json(force = True)

知识问答

使用Python请求发布JSON

2021年7月25日 Python实用宝典

问题：使用Python请求发布JSON

我需要将JSON从客户端发布到服务器。我正在使用Python 2.7.1和simplejson。客户端正在使用请求。服务器是CherryPy。我可以从服务器获取硬编码的JSON（代码未显示），但是当我尝试将JSON POST到服务器时，会收到“ 400 Bad Request”。

这是我的客户代码：

data = {'sender':   'Alice',
    'receiver': 'Bob',
    'message':  'We did it!'}
data_json = simplejson.dumps(data)
payload = {'json_payload': data_json}
r = requests.post("http://localhost:8080", data=payload)

这是服务器代码。

class Root(object):

    def __init__(self, content):
        self.content = content
        print self.content  # this works

    exposed = True

    def GET(self):
        cherrypy.response.headers['Content-Type'] = 'application/json'
        return simplejson.dumps(self.content)

    def POST(self):
        self.content = simplejson.loads(cherrypy.request.body.read())

有任何想法吗？

I need to POST a JSON from a client to a server. I’m using Python 2.7.1 and simplejson. The client is using Requests. The server is CherryPy. I can GET a hard-coded JSON from the server (code not shown), but when I try to POST a JSON to the server, I get “400 Bad Request”.

Here is my client code:

data = {'sender':   'Alice',
    'receiver': 'Bob',
    'message':  'We did it!'}
data_json = simplejson.dumps(data)
payload = {'json_payload': data_json}
r = requests.post("http://localhost:8080", data=payload)

Here is the server code.

class Root(object):

    def __init__(self, content):
        self.content = content
        print self.content  # this works

    exposed = True

    def GET(self):
        cherrypy.response.headers['Content-Type'] = 'application/json'
        return simplejson.dumps(self.content)

    def POST(self):
        self.content = simplejson.loads(cherrypy.request.body.read())

Any ideas?

回答 0

从Requests 2.4.2及更高版本开始，您可以在调用中使用’json’参数，从而使其更简单。

>>> import requests
>>> r = requests.post('http://httpbin.org/post', json={"key": "value"})
>>> r.status_code
200
>>> r.json()
{'args': {},
 'data': '{"key": "value"}',
 'files': {},
 'form': {},
 'headers': {'Accept': '*/*',
             'Accept-Encoding': 'gzip, deflate',
             'Connection': 'close',
             'Content-Length': '16',
             'Content-Type': 'application/json',
             'Host': 'httpbin.org',
             'User-Agent': 'python-requests/2.4.3 CPython/3.4.0',
             'X-Request-Id': 'xx-xx-xx'},
 'json': {'key': 'value'},
 'origin': 'x.x.x.x',
 'url': 'http://httpbin.org/post'}

编辑：此功能已添加到官方文档中。您可以在这里查看：请求文档

As of Requests version 2.4.2 and onwards, you can alternatively use ‘json’ parameter in the call which makes it simpler.

>>> import requests
>>> r = requests.post('http://httpbin.org/post', json={"key": "value"})
>>> r.status_code
200
>>> r.json()
{'args': {},
 'data': '{"key": "value"}',
 'files': {},
 'form': {},
 'headers': {'Accept': '*/*',
             'Accept-Encoding': 'gzip, deflate',
             'Connection': 'close',
             'Content-Length': '16',
             'Content-Type': 'application/json',
             'Host': 'httpbin.org',
             'User-Agent': 'python-requests/2.4.3 CPython/3.4.0',
             'X-Request-Id': 'xx-xx-xx'},
 'json': {'key': 'value'},
 'origin': 'x.x.x.x',
 'url': 'http://httpbin.org/post'}

EDIT: This feature has been added to the official documentation. You can view it here: Requests documentation

回答 1

原来我缺少标题信息。以下作品：

url = "http://localhost:8080"
data = {'sender': 'Alice', 'receiver': 'Bob', 'message': 'We did it!'}
headers = {'Content-type': 'application/json', 'Accept': 'text/plain'}
r = requests.post(url, data=json.dumps(data), headers=headers)

It turns out I was missing the header information. The following works:

url = "http://localhost:8080"
data = {'sender': 'Alice', 'receiver': 'Bob', 'message': 'We did it!'}
headers = {'Content-type': 'application/json', 'Accept': 'text/plain'}
r = requests.post(url, data=json.dumps(data), headers=headers)

回答 2

从请求2.4.2（https://pypi.python.org/pypi/requests）开始，支持“ json”参数。无需指定“ Content-Type”。因此，较短的版本：

requests.post('http://httpbin.org/post', json={'test': 'cheers'})

From requests 2.4.2 (https://pypi.python.org/pypi/requests), the “json” parameter is supported. No need to specify “Content-Type”. So the shorter version:

requests.post('http://httpbin.org/post', json={'test': 'cheers'})

回答 3

更好的方法是：

url = "http://xxx.xxxx.xx"

datas = {"cardno":"6248889874650987","systemIdentify":"s08","sourceChannel": 12}

headers = {'Content-type': 'application/json'}

rsp = requests.post(url, json=datas, headers=headers)

The better way is：

url = "http://xxx.xxxx.xx"

datas = {"cardno":"6248889874650987","systemIdentify":"s08","sourceChannel": 12}

headers = {'Content-type': 'application/json'}

rsp = requests.post(url, json=datas, headers=headers)

回答 4

与python 3.5+完美搭配

客户：

import requests
data = {'sender':   'Alice',
    'receiver': 'Bob',
    'message':  'We did it!'}
r = requests.post("http://localhost:8080", json={'json_payload': data})

服务器：

class Root(object):

    def __init__(self, content):
        self.content = content
        print self.content  # this works

    exposed = True

    def GET(self):
        cherrypy.response.headers['Content-Type'] = 'application/json'
        return simplejson.dumps(self.content)

    @cherrypy.tools.json_in()
    @cherrypy.tools.json_out()
    def POST(self):
        self.content = cherrypy.request.json
        return {'status': 'success', 'message': 'updated'}

Works perfectly with python 3.5+

client:

import requests
data = {'sender':   'Alice',
    'receiver': 'Bob',
    'message':  'We did it!'}
r = requests.post("http://localhost:8080", json={'json_payload': data})

server:

class Root(object):

    def __init__(self, content):
        self.content = content
        print self.content  # this works

    exposed = True

    def GET(self):
        cherrypy.response.headers['Content-Type'] = 'application/json'
        return simplejson.dumps(self.content)

    @cherrypy.tools.json_in()
    @cherrypy.tools.json_out()
    def POST(self):
        self.content = cherrypy.request.json
        return {'status': 'success', 'message': 'updated'}

回答 5

应该使用（data / json / files）之间的哪个参数，它实际上取决于名为ContentType的请求标头（通常通过浏览器的开发人员工具进行检查），

当Content-Type为application / x-www-form-urlencoded时，代码应为：

requests.post(url, data=jsonObj)

当Content-Type为application / json时，您的代码应为以下之一：

requests.post(url, json=jsonObj)

requests.post(url, data=jsonstr, headers={"Content-Type":"application/json"})

当Content-Type为multipart / form-data时，它用于上传文件，因此您的代码应为：

requests.post(url, files=xxxx)

Which parameter between (data / json / files) should be used,it’s actually depends on a request header named ContentType(usually check this through developer tools of your browser),

when the Content-Type is application/x-www-form-urlencoded, code should be:

requests.post(url, data=jsonObj)

when the Content-Type is application/json, your code is supposed to be one of below:

requests.post(url, json=jsonObj)

requests.post(url, data=jsonstr, headers={"Content-Type":"application/json"})

when the Content-Type is multipart/form-data, it’s used to upload files, so your code should be:

requests.post(url, files=xxxx)

知识问答

将utf-8文本保存在json.dumps中为UTF8，而不是\ u转义序列

2021年7月25日 Python实用宝典

问题：将utf-8文本保存在json.dumps中为UTF8，而不是\ u转义序列

样例代码：

>>> import json
>>> json_string = json.dumps("ברי צקלה")
>>> print json_string
"\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4"

问题：这不是人类可读的。我的（智能）用户想要使用JSON转储来验证甚至编辑文本文件（我宁愿不使用XML）。

有没有一种方法可以将对象序列化为UTF-8 JSON字符串（而不是 \uXXXX）？

sample code:

>>> import json
>>> json_string = json.dumps("ברי צקלה")
>>> print json_string
"\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4"

The problem: it’s not human readable. My (smart) users want to verify or even edit text files with JSON dumps (and I’d rather not use XML).

Is there a way to serialize objects into UTF-8 JSON strings (instead of \uXXXX)?

回答 0

使用ensure_ascii=False切换至json.dumps()，然后手动将值编码为UTF-8：

>>> json_string = json.dumps("ברי צקלה", ensure_ascii=False).encode('utf8')
>>> json_string
b'"\xd7\x91\xd7\xa8\xd7\x99 \xd7\xa6\xd7\xa7\xd7\x9c\xd7\x94"'
>>> print(json_string.decode())
"ברי צקלה"

如果要写入文件，只需使用json.dump()并将其留给文件对象进行编码：

with open('filename', 'w', encoding='utf8') as json_file:
    json.dump("ברי צקלה", json_file, ensure_ascii=False)

Python 2警告

对于Python 2，还有更多注意事项需要考虑。如果要将其写入文件，则可以使用io.open()代替open()来生成一个文件对象，该对象在编写时为您编码Unicode值，然后使用json.dump()代替来写入该文件：

with io.open('filename', 'w', encoding='utf8') as json_file:
    json.dump(u"ברי צקלה", json_file, ensure_ascii=False)

做笔记，有一对在错误json模块，其中ensure_ascii=False标志可以产生一个混合的unicode和str对象。那么，Python 2的解决方法是：

with io.open('filename', 'w', encoding='utf8') as json_file:
    data = json.dumps(u"ברי צקלה", ensure_ascii=False)
    # unicode(data) auto-decodes data to unicode if str
    json_file.write(unicode(data))

在Python 2中，当使用str编码为UTF-8的字节字符串（类型）时，请确保还设置encoding关键字：

>>> d={ 1: "ברי צקלה", 2: u"ברי צקלה" }
>>> d
{1: '\xd7\x91\xd7\xa8\xd7\x99 \xd7\xa6\xd7\xa7\xd7\x9c\xd7\x94', 2: u'\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4'}

>>> s=json.dumps(d, ensure_ascii=False, encoding='utf8')
>>> s
u'{"1": "\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4", "2": "\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4"}'
>>> json.loads(s)['1']
u'\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4'
>>> json.loads(s)['2']
u'\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4'
>>> print json.loads(s)['1']
ברי צקלה
>>> print json.loads(s)['2']
ברי צקלה

Use the ensure_ascii=False switch to json.dumps(), then encode the value to UTF-8 manually:

>>> json_string = json.dumps("ברי צקלה", ensure_ascii=False).encode('utf8')
>>> json_string
b'"\xd7\x91\xd7\xa8\xd7\x99 \xd7\xa6\xd7\xa7\xd7\x9c\xd7\x94"'
>>> print(json_string.decode())
"ברי צקלה"

If you are writing to a file, just use json.dump() and leave it to the file object to encode:

with open('filename', 'w', encoding='utf8') as json_file:
    json.dump("ברי צקלה", json_file, ensure_ascii=False)

Caveats for Python 2

For Python 2, there are some more caveats to take into account. If you are writing this to a file, you can use io.open() instead of open() to produce a file object that encodes Unicode values for you as you write, then use json.dump() instead to write to that file:

with io.open('filename', 'w', encoding='utf8') as json_file:
    json.dump(u"ברי צקלה", json_file, ensure_ascii=False)

Do note that there is a bug in the json module where the ensure_ascii=False flag can produce a mix of unicode and str objects. The workaround for Python 2 then is:

with io.open('filename', 'w', encoding='utf8') as json_file:
    data = json.dumps(u"ברי צקלה", ensure_ascii=False)
    # unicode(data) auto-decodes data to unicode if str
    json_file.write(unicode(data))

In Python 2, when using byte strings (type str), encoded to UTF-8, make sure to also set the encoding keyword:

>>> d={ 1: "ברי צקלה", 2: u"ברי צקלה" }
>>> d
{1: '\xd7\x91\xd7\xa8\xd7\x99 \xd7\xa6\xd7\xa7\xd7\x9c\xd7\x94', 2: u'\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4'}

>>> s=json.dumps(d, ensure_ascii=False, encoding='utf8')
>>> s
u'{"1": "\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4", "2": "\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4"}'
>>> json.loads(s)['1']
u'\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4'
>>> json.loads(s)['2']
u'\u05d1\u05e8\u05d9 \u05e6\u05e7\u05dc\u05d4'
>>> print json.loads(s)['1']
ברי צקלה
>>> print json.loads(s)['2']
ברי צקלה

回答 1

写入文件

import codecs
import json

with codecs.open('your_file.txt', 'w', encoding='utf-8') as f:
    json.dump({"message":"xin chào việt nam"}, f, ensure_ascii=False)

打印到标准输出

import json
print(json.dumps({"message":"xin chào việt nam"}, ensure_ascii=False))

To write to a file

import codecs
import json

with codecs.open('your_file.txt', 'w', encoding='utf-8') as f:
    json.dump({"message":"xin chào việt nam"}, f, ensure_ascii=False)

To print to stdout

import json
print(json.dumps({"message":"xin chào việt nam"}, ensure_ascii=False))

回答 2

更新：这是错误的答案，但是了解为什么它仍然是有用的。看评论。

怎么unicode-escape样

>>> d = {1: "ברי צקלה", 2: u"ברי צקלה"}
>>> json_str = json.dumps(d).decode('unicode-escape').encode('utf8')
>>> print json_str
{"1": "ברי צקלה", "2": "ברי צקלה"}

UPDATE: This is wrong answer, but it’s still useful to understand why it’s wrong. See comments.

How about unicode-escape?

>>> d = {1: "ברי צקלה", 2: u"ברי צקלה"}
>>> json_str = json.dumps(d).decode('unicode-escape').encode('utf8')
>>> print json_str
{"1": "ברי צקלה", "2": "ברי צקלה"}

回答 3

Peters的python 2解决方法在边缘情况下失败：

d = {u'keyword': u'bad credit  \xe7redit cards'}
with io.open('filename', 'w', encoding='utf8') as json_file:
    data = json.dumps(d, ensure_ascii=False).decode('utf8')
    try:
        json_file.write(data)
    except TypeError:
        # Decode data to Unicode first
        json_file.write(data.decode('utf8'))

UnicodeEncodeError: 'ascii' codec can't encode character u'\xe7' in position 25: ordinal not in range(128)

它在第3行的.decode（’utf8’）部分崩溃。我通过避免该步骤以及ascii的特殊大小写，使程序更加简单，从而解决了该问题：

with io.open('filename', 'w', encoding='utf8') as json_file:
  data = json.dumps(d, ensure_ascii=False, encoding='utf8')
  json_file.write(unicode(data))

cat filename
{"keyword": "bad credit  çredit cards"}

Peters’ python 2 workaround fails on an edge case:

d = {u'keyword': u'bad credit  \xe7redit cards'}
with io.open('filename', 'w', encoding='utf8') as json_file:
    data = json.dumps(d, ensure_ascii=False).decode('utf8')
    try:
        json_file.write(data)
    except TypeError:
        # Decode data to Unicode first
        json_file.write(data.decode('utf8'))

UnicodeEncodeError: 'ascii' codec can't encode character u'\xe7' in position 25: ordinal not in range(128)

It was crashing on the .decode(‘utf8’) part of line 3. I fixed the problem by making the program much simpler by avoiding that step as well as the special casing of ascii:

with io.open('filename', 'w', encoding='utf8') as json_file:
  data = json.dumps(d, ensure_ascii=False, encoding='utf8')
  json_file.write(unicode(data))

cat filename
{"keyword": "bad credit  çredit cards"}

回答 4

从Python 3.7开始，以下代码可以正常运行：

from json import dumps
result = {"symbol": "ƒ"}
json_string = dumps(result, sort_keys=True, indent=2, ensure_ascii=False)
print(json_string)

输出：

{"symbol": "ƒ"}

As of Python 3.7 the following code works fine:

from json import dumps
result = {"symbol": "ƒ"}
json_string = dumps(result, sort_keys=True, indent=2, ensure_ascii=False)
print(json_string)

Output:

{"symbol": "ƒ"}

回答 5

以下是我和google的var阅读答案。

# coding:utf-8
r"""
@update: 2017-01-09 14:44:39
@explain: str, unicode, bytes in python2to3
    #python2 UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 7: ordinal not in range(128)
    #1.reload
    #importlib,sys
    #importlib.reload(sys)
    #sys.setdefaultencoding('utf-8') #python3 don't have this attribute.
    #not suggest even in python2 #see:http://stackoverflow.com/questions/3828723/why-should-we-not-use-sys-setdefaultencodingutf-8-in-a-py-script
    #2.overwrite /usr/lib/python2.7/sitecustomize.py or (sitecustomize.py and PYTHONPATH=".:$PYTHONPATH" python)
    #too complex
    #3.control by your own (best)
    #==> all string must be unicode like python3 (u'xx'|b'xx'.encode('utf-8')) (unicode 's disappeared in python3)
    #see: http://blog.ernest.me/post/python-setdefaultencoding-unicode-bytes

    #how to Saving utf-8 texts in json.dumps as UTF8, not as \u escape sequence
    #http://stackoverflow.com/questions/18337407/saving-utf-8-texts-in-json-dumps-as-utf8-not-as-u-escape-sequence
"""

from __future__ import print_function
import json

a = {"b": u"中文"}  # add u for python2 compatibility
print('%r' % a)
print('%r' % json.dumps(a))
print('%r' % (json.dumps(a).encode('utf8')))
a = {"b": u"中文"}
print('%r' % json.dumps(a, ensure_ascii=False))
print('%r' % (json.dumps(a, ensure_ascii=False).encode('utf8')))
# print(a.encode('utf8')) #AttributeError: 'dict' object has no attribute 'encode'
print('')

# python2:bytes=str; python3:bytes
b = a['b'].encode('utf-8')
print('%r' % b)
print('%r' % b.decode("utf-8"))
print('')

# python2:unicode; python3:str=unicode
c = b.decode('utf-8')
print('%r' % c)
print('%r' % c.encode('utf-8'))
"""
#python2
{'b': u'\u4e2d\u6587'}
'{"b": "\\u4e2d\\u6587"}'
'{"b": "\\u4e2d\\u6587"}'
u'{"b": "\u4e2d\u6587"}'
'{"b": "\xe4\xb8\xad\xe6\x96\x87"}'

'\xe4\xb8\xad\xe6\x96\x87'
u'\u4e2d\u6587'

u'\u4e2d\u6587'
'\xe4\xb8\xad\xe6\x96\x87'

#python3
{'b': '中文'}
'{"b": "\\u4e2d\\u6587"}'
b'{"b": "\\u4e2d\\u6587"}'
'{"b": "中文"}'
b'{"b": "\xe4\xb8\xad\xe6\x96\x87"}'

b'\xe4\xb8\xad\xe6\x96\x87'
'中文'

'中文'
b'\xe4\xb8\xad\xe6\x96\x87'
"""

The following is my understanding var reading answer above and google.

# coding:utf-8
r"""
@update: 2017-01-09 14:44:39
@explain: str, unicode, bytes in python2to3
    #python2 UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position 7: ordinal not in range(128)
    #1.reload
    #importlib,sys
    #importlib.reload(sys)
    #sys.setdefaultencoding('utf-8') #python3 don't have this attribute.
    #not suggest even in python2 #see:http://stackoverflow.com/questions/3828723/why-should-we-not-use-sys-setdefaultencodingutf-8-in-a-py-script
    #2.overwrite /usr/lib/python2.7/sitecustomize.py or (sitecustomize.py and PYTHONPATH=".:$PYTHONPATH" python)
    #too complex
    #3.control by your own (best)
    #==> all string must be unicode like python3 (u'xx'|b'xx'.encode('utf-8')) (unicode 's disappeared in python3)
    #see: http://blog.ernest.me/post/python-setdefaultencoding-unicode-bytes

    #how to Saving utf-8 texts in json.dumps as UTF8, not as \u escape sequence
    #http://stackoverflow.com/questions/18337407/saving-utf-8-texts-in-json-dumps-as-utf8-not-as-u-escape-sequence
"""

from __future__ import print_function
import json

a = {"b": u"中文"}  # add u for python2 compatibility
print('%r' % a)
print('%r' % json.dumps(a))
print('%r' % (json.dumps(a).encode('utf8')))
a = {"b": u"中文"}
print('%r' % json.dumps(a, ensure_ascii=False))
print('%r' % (json.dumps(a, ensure_ascii=False).encode('utf8')))
# print(a.encode('utf8')) #AttributeError: 'dict' object has no attribute 'encode'
print('')

# python2:bytes=str; python3:bytes
b = a['b'].encode('utf-8')
print('%r' % b)
print('%r' % b.decode("utf-8"))
print('')

# python2:unicode; python3:str=unicode
c = b.decode('utf-8')
print('%r' % c)
print('%r' % c.encode('utf-8'))
"""
#python2
{'b': u'\u4e2d\u6587'}
'{"b": "\\u4e2d\\u6587"}'
'{"b": "\\u4e2d\\u6587"}'
u'{"b": "\u4e2d\u6587"}'
'{"b": "\xe4\xb8\xad\xe6\x96\x87"}'

'\xe4\xb8\xad\xe6\x96\x87'
u'\u4e2d\u6587'

u'\u4e2d\u6587'
'\xe4\xb8\xad\xe6\x96\x87'

#python3
{'b': '中文'}
'{"b": "\\u4e2d\\u6587"}'
b'{"b": "\\u4e2d\\u6587"}'
'{"b": "中文"}'
b'{"b": "\xe4\xb8\xad\xe6\x96\x87"}'

b'\xe4\xb8\xad\xe6\x96\x87'
'中文'

'中文'
b'\xe4\xb8\xad\xe6\x96\x87'
"""

回答 6

这是我使用json.dump（）的解决方案：

def jsonWrite(p, pyobj, ensure_ascii=False, encoding=SYSTEM_ENCODING, **kwargs):
    with codecs.open(p, 'wb', 'utf_8') as fileobj:
        json.dump(pyobj, fileobj, ensure_ascii=ensure_ascii,encoding=encoding, **kwargs)

其中SYSTEM_ENCODING设置为：

locale.setlocale(locale.LC_ALL, '')
SYSTEM_ENCODING = locale.getlocale()[1]

Here’s my solution using json.dump():

def jsonWrite(p, pyobj, ensure_ascii=False, encoding=SYSTEM_ENCODING, **kwargs):
    with codecs.open(p, 'wb', 'utf_8') as fileobj:
        json.dump(pyobj, fileobj, ensure_ascii=ensure_ascii,encoding=encoding, **kwargs)

where SYSTEM_ENCODING is set to:

locale.setlocale(locale.LC_ALL, '')
SYSTEM_ENCODING = locale.getlocale()[1]

回答 7

尽可能使用编解码器，

with codecs.open('file_path', 'a+', 'utf-8') as fp:
    fp.write(json.dumps(res, ensure_ascii=False))

Use codecs if possible,

with codecs.open('file_path', 'a+', 'utf-8') as fp:
    fp.write(json.dumps(res, ensure_ascii=False))

回答 8

感谢您在这里的原始答案。使用python 3的以下代码行：

print(json.dumps(result_dict,ensure_ascii=False))

还可以如果不是必须的，请考虑尝试在代码中不要写太多文本。

这对于python控制台可能已经足够了。但是，要使服务器满意，您可能需要按照此处的说明设置语言环境（如果它在apache2上） http://blog.dscpl.com.au/2014/09/setting-lang-and-lcall-when-using .html

基本上在ubuntu上安装he_IL或任何语言环境，检查是否未安装

locale -a

将其安装在XX是您的语言的位置

sudo apt-get install language-pack-XX

例如：

sudo apt-get install language-pack-he

将以下文本添加到/ etc / apache2 / envvrs

export LANG='he_IL.UTF-8'
export LC_ALL='he_IL.UTF-8'

比您希望不要从apache上得到python错误：

打印（js）UnicodeEncodeError：’ascii’编解码器无法在位置41-45处编码字符：序数不在范围内（128）

另外，在apache中，尝试将utf设置为默认编码，如下所示：
如何将Apache的默认编码更改为UTF-8？

尽早执行，因为apache错误可能很难调试，并且您可能会错误地认为它来自python，在这种情况下可能并非如此

Thanks for the original answer here. With python 3 the following line of code:

print(json.dumps(result_dict,ensure_ascii=False))

was ok. Consider trying not writing too much text in the code if it’s not imperative.

This might be good enough for the python console. However, to satisfy a server you might need to set the locale as explained here (if it is on apache2) http://blog.dscpl.com.au/2014/09/setting-lang-and-lcall-when-using.html

basically install he_IL or whatever language locale on ubuntu check it is not installed

locale -a

install it where XX is your language

sudo apt-get install language-pack-XX

For example:

sudo apt-get install language-pack-he

add the following text to /etc/apache2/envvrs

export LANG='he_IL.UTF-8'
export LC_ALL='he_IL.UTF-8'

Than you would hopefully not get python errors on from apache like:

print (js) UnicodeEncodeError: ‘ascii’ codec can’t encode characters in position 41-45: ordinal not in range(128)

Also in apache try to make utf the default encoding as explained here:
How to change the default encoding to UTF-8 for Apache?

Do it early because apache errors can be pain to debug and you can mistakenly think it’s from python which possibly isn’t the case in that situation

回答 9

如果要从文件和文件内容阿拉伯文本加载JSON字符串。然后这将起作用。

假设文件如下：arabic.json

{ 
"key1" : "لمستخدمين",
"key2" : "إضافة مستخدم"
}

从arabic.json文件获取阿拉伯语内容

with open(arabic.json, encoding='utf-8') as f:
   # deserialises it
   json_data = json.load(f)
   f.close()


# json formatted string
json_data2 = json.dumps(json_data, ensure_ascii = False)

要在Django模板中使用JSON数据，请执行以下步骤：

# If have to get the JSON index in Django Template file, then simply decode the encoded string.

json.JSONDecoder().decode(json_data2)

完成了！现在我们可以将结果作为带有阿拉伯值的JSON索引来获取。

If you are loading JSON string from a file & file contents arabic texts. Then this will work.

Assume File like: arabic.json

{ 
"key1" : "لمستخدمين",
"key2" : "إضافة مستخدم"
}

Get the arabic contents from the arabic.json file

with open(arabic.json, encoding='utf-8') as f:
   # deserialises it
   json_data = json.load(f)
   f.close()


# json formatted string
json_data2 = json.dumps(json_data, ensure_ascii = False)

To use JSON Data in Django Template follow below steps:

# If have to get the JSON index in Django Template file, then simply decode the encoded string.

json.JSONDecoder().decode(json_data2)

done! Now we can get the results as JSON index with arabic value.

回答 10

使用unicode-escape解决问题

>>>import json
>>>json_string = json.dumps("ברי צקלה")
>>>json_string.encode('ascii').decode('unicode-escape')
'"ברי צקלה"'

说明

>>>s = '漢  χαν  хан'
>>>print('unicode: ' + s.encode('unicode-escape').decode('utf-8'))
unicode: \u6f22  \u03c7\u03b1\u03bd  \u0445\u0430\u043d

>>>u = s.encode('unicode-escape').decode('utf-8')
>>>print('original: ' + u.encode("utf-8").decode('unicode-escape'))
original: 漢  χαν  хан

原始资源：https : //blog.csdn.net/chuatony/article/details/72628868

use unicode-escape to solve problem

>>>import json
>>>json_string = json.dumps("ברי צקלה")
>>>json_string.encode('ascii').decode('unicode-escape')
'"ברי צקלה"'

explain

>>>s = '漢  χαν  хан'
>>>print('unicode: ' + s.encode('unicode-escape').decode('utf-8'))
unicode: \u6f22  \u03c7\u03b1\u03bd  \u0445\u0430\u043d

>>>u = s.encode('unicode-escape').decode('utf-8')
>>>print('original: ' + u.encode("utf-8").decode('unicode-escape'))
original: 漢  χαν  хан

original resource：https://blog.csdn.net/chuatony/article/details/72628868

回答 11

正如Martijn指出的那样，在json.dumps中使用suresure_ascii = False是解决此问题的正确方向。但是，这可能会引发异常：

UnicodeDecodeError: 'ascii' codec can't decode byte 0xe7 in position 1: ordinal not in range(128)

您需要在site.py或sitecustomize.py中进行其他设置，才能正确设置sys.getdefaultencoding（）。site.py在lib / python2.7 /下，sitecustomize.py在lib / python2.7 / site-packages下。

如果要使用site.py，请在def setencoding（）下：将第一个if 0：更改为if 1 :，以便python使用操作系统的语言环境。

如果您喜欢使用sitecustomize.py，那么如果尚未创建，则可能不存在。只需将这些行：

import sys
reload(sys)
sys.setdefaultencoding('utf-8')

然后，您可以以utf-8格式进行中文json输出，例如：

name = {"last_name": u"王"}
json.dumps(name, ensure_ascii=False)

您将获得一个utf-8编码的字符串，而不是\ u转义的json字符串。

验证默认编码：

print sys.getdefaultencoding()

您应该获得“ utf-8”或“ UTF-8”来验证site.py或sitecustomize.py设置。

请注意，您无法在交互式python控制台上执行sys.setdefaultencoding（“ utf-8”）。

Using ensure_ascii=False in json.dumps is the right direction to solve this problem, as pointed out by Martijn. However, this may raise an exception:

UnicodeDecodeError: 'ascii' codec can't decode byte 0xe7 in position 1: ordinal not in range(128)

You need extra settings in either site.py or sitecustomize.py to set your sys.getdefaultencoding() correct. site.py is under lib/python2.7/ and sitecustomize.py is under lib/python2.7/site-packages.

If you want to use site.py, under def setencoding(): change the first if 0: to if 1: so that python will use your operation system’s locale.

If you prefer to use sitecustomize.py, which may not exist if you haven’t created it. simply put these lines:

import sys
reload(sys)
sys.setdefaultencoding('utf-8')

Then you can do some Chinese json output in utf-8 format, such as:

name = {"last_name": u"王"}
json.dumps(name, ensure_ascii=False)

You will get an utf-8 encoded string, rather than \u escaped json string.

To verify your default encoding:

print sys.getdefaultencoding()

You should get “utf-8” or “UTF-8” to verify your site.py or sitecustomize.py settings.

Please note that you could not do sys.setdefaultencoding(“utf-8”) at interactive python console.

知识问答

从Flask视图返回JSON响应

2021年7月25日 Python实用宝典

问题：从Flask视图返回JSON响应

我有一个函数，可使用Pandas分析CSV文件并生成带有摘要信息的字典。我想从Flask视图返回结果作为响应。如何返回JSON响应？

@app.route("/summary")
def summary():
    d = make_summary()
    # send it back as json

I have a function that analyzes a CSV file with Pandas and produces a dict with summary information. I want to return the results as a response from a Flask view. How do I return a JSON response?

@app.route("/summary")
def summary():
    d = make_summary()
    # send it back as json

回答 0

将摘要数据传递给该jsonify函数，该函数返回JSON响应。

from flask import jsonify

@app.route('/summary')
def summary():
    d = make_summary()
    return jsonify(d)

从Flask 0.11开始，您可以将任何JSON可序列化的类型（不仅是dict）传递为顶级对象。

Pass the summary data to the jsonify function, which returns a JSON response.

from flask import jsonify

@app.route('/summary')
def summary():
    d = make_summary()
    return jsonify(d)

As of Flask 0.11, you can pass any JSON-serializable type, not just dict, as the top level object.

回答 1

jsonify序列化您传递给JSON的数据。如果您想自己序列化数据，请jsonify使用status=200和构建响应以执行操作mimetype='application/json'。

from flask import json

@app.route('/summary')
def summary():
    data = make_summary()
    response = app.response_class(
        response=json.dumps(data),
        status=200,
        mimetype='application/json'
    )
    return response

jsonify serializes the data you pass it to JSON. If you want to serialize the data yourself, do what jsonify does by building a response with status=200 and mimetype='application/json'.

from flask import json

@app.route('/summary')
def summary():
    data = make_summary()
    response = app.response_class(
        response=json.dumps(data),
        status=200,
        mimetype='application/json'
    )
    return response

回答 2

将关键字参数传递给flask.jsonify，它们将作为JSON对象输出。

@app.route('/_get_current_user')
def get_current_user():
    return jsonify(
        username=g.user.username,
        email=g.user.email,
        id=g.user.id
    )

{
    "username": "admin",
    "email": "admin@localhost",
    "id": 42
}

如果您已有字典，则可以将其直接传递为jsonify(d)。

Pass keyword arguments to flask.jsonify and they will be output as a JSON object.

@app.route('/_get_current_user')
def get_current_user():
    return jsonify(
        username=g.user.username,
        email=g.user.email,
        id=g.user.id
    )

{
    "username": "admin",
    "email": "admin@localhost",
    "id": 42
}

If you already have a dict, you can pass it directly as jsonify(d).

回答 3

如果jsonify由于某种原因不想使用，则可以手动执行。调用flask.json.dumps以创建JSON数据，然后返回application/json内容类型的响应。

from flask import json

@app.route('/summary')
def summary():
    data = make_summary()
    response = app.response_class(
        response=json.dumps(data),
        mimetype='application/json'
    )
    return response

flask.json与内置json模块不同。simplejson如果可用，它将使用速度更快的模块，并与Flask应用进行各种集成。

If you don’t want to use jsonify for some reason, you can do what it does manually. Call flask.json.dumps to create JSON data, then return a response with the application/json content type.

from flask import json

@app.route('/summary')
def summary():
    data = make_summary()
    response = app.response_class(
        response=json.dumps(data),
        mimetype='application/json'
    )
    return response

flask.json is distinct from the built-in json module. It will use the faster simplejson module if available, and enables various integrations with your Flask app.

回答 4

如果您要分析用户上传的文件，则Flask 快速入门会显示如何从用户那里获取文件并进行访问。从中获取文件request.files并将其传递给摘要函数。

from flask import request, jsonify
from werkzeug import secure_filename

@app.route('/summary', methods=['GET', 'POST'])
def summary():
    if request.method == 'POST':
        csv = request.files['data']
        return jsonify(
            summary=make_summary(csv),
            csv_name=secure_filename(csv.filename)
        )

    return render_template('submit_data.html')

将'data'键替换为request.filesHTML表单中输入的文件名。

If you want to analyze a file uploaded by the user, the Flask quickstart shows how to get files from users and access them. Get the file from request.files and pass it to the summary function.

from flask import request, jsonify
from werkzeug import secure_filename

@app.route('/summary', methods=['GET', 'POST'])
def summary():
    if request.method == 'POST':
        csv = request.files['data']
        return jsonify(
            summary=make_summary(csv),
            csv_name=secure_filename(csv.filename)
        )

    return render_template('submit_data.html')

Replace the 'data' key for request.files with the name of the file input in your HTML form.

回答 5

要返回JSON响应并设置状态代码，您可以使用make_response：

from flask import jsonify, make_response

@app.route('/summary')
def summary():
    d = make_summary()
    return make_response(jsonify(d), 200)

Flask问题跟踪器中此注释的启发。

To return a JSON response and set a status code you can use make_response:

from flask import jsonify, make_response

@app.route('/summary')
def summary():
    d = make_summary()
    return make_response(jsonify(d), 200)

Inspiration taken from this comment in the Flask issue tracker.

回答 6

从版本1.1.0 Flask开始，如果视图返回dict，它将被转换为JSON response。

@app.route("/users", methods=['GET'])
def get_user():
    return {
        "user": "John Doe",
    }

As of version 1.1.0 Flask, if a view returns a dict it will be turned into a JSON response.

@app.route("/users", methods=['GET'])
def get_user():
    return {
        "user": "John Doe",
    }

回答 7

我使用装饰器返回的结果jsonfiy。我认为当视图具有多个返回值时，它更具可读性。这不支持返回类似的元组content, status，但是我将使用返回app.errorhandler来处理错误状态。

import functools
from flask import jsonify

def return_json(f):
    @functools.wraps(f)
    def inner(**kwargs):
        return jsonify(f(**kwargs))

    return inner

@app.route('/test/<arg>')
@return_json
def test(arg):
    if arg == 'list':
        return [1, 2, 3]
    elif arg == 'dict':
        return {'a': 1, 'b': 2}
    elif arg == 'bool':
        return True
    return 'none of them'

I use a decorator to return the result of jsonfiy. I think it is more readable when a view has multiple returns. This does not support returning a tuple like content, status, but I handle returning error statuses with app.errorhandler instead.

import functools
from flask import jsonify

def return_json(f):
    @functools.wraps(f)
    def inner(**kwargs):
        return jsonify(f(**kwargs))

    return inner

@app.route('/test/<arg>')
@return_json
def test(arg):
    if arg == 'list':
        return [1, 2, 3]
    elif arg == 'dict':
        return {'a': 1, 'b': 2}
    elif arg == 'bool':
        return True
    return 'none of them'

回答 8

在Flask 0.11之前，jsonfiy不允许直接返回数组。而是将列表作为关键字参数传递。

@app.route('/get_records')
def get_records():
    results = [
        {
          "rec_create_date": "12 Jun 2016",
          "rec_dietary_info": "nothing",
          "rec_dob": "01 Apr 1988",
          "rec_first_name": "New",
          "rec_last_name": "Guy",
        },
        {
          "rec_create_date": "1 Apr 2016",
          "rec_dietary_info": "Nut allergy",
          "rec_dob": "01 Feb 1988",
          "rec_first_name": "Old",
          "rec_last_name": "Guy",
        },
    ]
    return jsonify(results=list)

Prior to Flask 0.11, jsonfiy would not allow returning an array directly. Instead, pass the list as a keyword argument.

@app.route('/get_records')
def get_records():
    results = [
        {
          "rec_create_date": "12 Jun 2016",
          "rec_dietary_info": "nothing",
          "rec_dob": "01 Apr 1988",
          "rec_first_name": "New",
          "rec_last_name": "Guy",
        },
        {
          "rec_create_date": "1 Apr 2016",
          "rec_dietary_info": "Nut allergy",
          "rec_dob": "01 Feb 1988",
          "rec_first_name": "Old",
          "rec_last_name": "Guy",
        },
    ]
    return jsonify(results=list)

回答 9

在Flask 1.1中，如果返回字典，它将自动转换为JSON。因此，如果make_summary()返回字典，您可以

from flask import Flask

app = Flask(__name__)

@app.route('/summary')
def summary():
    d = make_summary()
    return d

要求包含状态码的SO已作为与此副本的副本被关闭。因此，要回答该问题，您可以通过返回形式的元组来包含状态代码(dict, int)。将dict转换为JSON，int将HTTP状态代码。没有任何输入，状态是默认的200。因此在上面的示例中，代码将是200。在下面的示例中，其代码更改为201。

from flask import Flask

app = Flask(__name__)

@app.route('/summary')
def summary():
    d = make_summary()
    return d, 201  # 200 is the default

您可以使用以下方法检查状态码

curl --request GET "http://127.0.0.1:5000/summary" -w "\ncode: %{http_code}\n\n"

In Flask 1.1, if you return a dictionary and it will automatically be converted into JSON. So if make_summary() returns a dictionary, you can

from flask import Flask

app = Flask(__name__)

@app.route('/summary')
def summary():
    d = make_summary()
    return d

The SO that asks about including the status code was closed as a duplicate to this one. So to also answer that question, you can include the status code by returning a tuple of the form (dict, int). The dict is converted to JSON and the int will be the HTTP Status Code. Without any input, the Status is the default 200. So in the above example the code would be 200. In the example below it is changed to 201.

from flask import Flask

app = Flask(__name__)

@app.route('/summary')
def summary():
    d = make_summary()
    return d, 201  # 200 is the default

You can check the status code using

curl --request GET "http://127.0.0.1:5000/summary" -w "\ncode: %{http_code}\n\n"

回答 10

如果是字典，则flask可以直接将其返回（版本1.0.2）

def summary():
    d = make_summary()
    return d, 200

if its a dict, flask can return it directly (Version 1.0.2)

def summary():
    d = make_summary()
    return d, 200

回答 11

“”“ 使用Flask基于类的视图 ”“”

from flask import Flask, request, jsonify

from flask.views import MethodView

app = Flask(**__name__**)

app.add_url_rule('/summary/', view_func=Summary.as_view('summary'))

class Summary(MethodView):

    def __init__(self):
        self.response = dict()

    def get(self):
        self.response['summary'] = make_summary()  # make_summary is a method to calculate the summary.
        return jsonify(self.response)

“”” Using Flask Class-base View “””

from flask import Flask, request, jsonify

from flask.views import MethodView

app = Flask(**__name__**)

app.add_url_rule('/summary/', view_func=Summary.as_view('summary'))

class Summary(MethodView):

    def __init__(self):
        self.response = dict()

    def get(self):
        self.response['summary'] = make_summary()  # make_summary is a method to calculate the summary.
        return jsonify(self.response)

回答 12

烧瓶1.1.x

现在Flask支持请求直接通过json返回，不再需要jsonify

@app.route("/")
def index():
    return {
        "api_stuff": "values",
    }

相当于

@app.route("/")
def index():
    return jsonify({
        "api_stuff": "values",
    })

Flask 1.1.x

now Flask support request return with json directly, jsonify not required anymore

@app.route("/")
def index():
    return {
        "api_stuff": "values",
    }

is equivalent to

@app.route("/")
def index():
    return jsonify({
        "api_stuff": "values",
    })

for more information read here https://medium.com/octopus-wealth/returning-json-from-flask-cf4ce6fe9aeb and https://github.com/pallets/flask/pull/3111

知识问答

使用Django和Python创建JSON响应

2021年7月25日 Python实用宝典

问题：使用Django和Python创建JSON响应

我正在尝试将服务器端Ajax响应脚本转换为Django HttpResponse，但显然无法正常工作。

这是服务器端脚本：

/* RECEIVE VALUE */
$validateValue=$_POST['validateValue'];
$validateId=$_POST['validateId'];
$validateError=$_POST['validateError'];

/* RETURN VALUE */
$arrayToJs = array();
$arrayToJs[0] = $validateId;
$arrayToJs[1] = $validateError;

if($validateValue =="Testuser"){  // Validate??
    $arrayToJs[2] = "true";       // RETURN TRUE
    echo '{"jsonValidateReturn":'.json_encode($arrayToJs).'}';  // RETURN ARRAY WITH success
}
else{
    for($x=0;$x<1000000;$x++){
        if($x == 990000){
            $arrayToJs[2] = "false";
            echo '{"jsonValidateReturn":'.json_encode($arrayToJs).'}';   // RETURNS ARRAY WITH ERROR.
        }
    }
}

这是转换后的代码

def validate_user(request):
    if request.method == 'POST':
        vld_value = request.POST.get('validateValue')
        vld_id = request.POST.get('validateId')
        vld_error = request.POST.get('validateError')

        array_to_js = [vld_id, vld_error, False]

        if vld_value == "TestUser":
            array_to_js[2] = True
            x = simplejson.dumps(array_to_js)
            return HttpResponse(x)
        else:
            array_to_js[2] = False
            x = simplejson.dumps(array_to_js)
            error = 'Error'
            return render_to_response('index.html',{'error':error},context_instance=RequestContext(request))
    return render_to_response('index.html',context_instance=RequestContext(request))

我正在使用simplejson对Python列表进行编码（因此它将返回JSON数组）。我还不能解决问题。但是我认为我对“回声”做错了。

I’m trying to convert a server side Ajax response script into a Django HttpResponse, but apparently it’s not working.

This is the server-side script:

/* RECEIVE VALUE */
$validateValue=$_POST['validateValue'];
$validateId=$_POST['validateId'];
$validateError=$_POST['validateError'];

/* RETURN VALUE */
$arrayToJs = array();
$arrayToJs[0] = $validateId;
$arrayToJs[1] = $validateError;

if($validateValue =="Testuser"){  // Validate??
    $arrayToJs[2] = "true";       // RETURN TRUE
    echo '{"jsonValidateReturn":'.json_encode($arrayToJs).'}';  // RETURN ARRAY WITH success
}
else{
    for($x=0;$x<1000000;$x++){
        if($x == 990000){
            $arrayToJs[2] = "false";
            echo '{"jsonValidateReturn":'.json_encode($arrayToJs).'}';   // RETURNS ARRAY WITH ERROR.
        }
    }
}

And this is the converted code

def validate_user(request):
    if request.method == 'POST':
        vld_value = request.POST.get('validateValue')
        vld_id = request.POST.get('validateId')
        vld_error = request.POST.get('validateError')

        array_to_js = [vld_id, vld_error, False]

        if vld_value == "TestUser":
            array_to_js[2] = True
            x = simplejson.dumps(array_to_js)
            return HttpResponse(x)
        else:
            array_to_js[2] = False
            x = simplejson.dumps(array_to_js)
            error = 'Error'
            return render_to_response('index.html',{'error':error},context_instance=RequestContext(request))
    return render_to_response('index.html',context_instance=RequestContext(request))

I’m using simplejson to encode the Python list (so it will return a JSON array). I couldn’t figure out the problem yet. But I think that I did something wrong about the ‘echo’.

回答 0

我通常使用字典，而不是列表来返回JSON内容。

import json

from django.http import HttpResponse

response_data = {}
response_data['result'] = 'error'
response_data['message'] = 'Some error message'

在Django 1.7之前的版本中，您将像这样返回它：

return HttpResponse(json.dumps(response_data), content_type="application/json")

对于Django 1.7+，请JsonResponse按照以下SO答案所示使用：

from django.http import JsonResponse
return JsonResponse({'foo':'bar'})

I usually use a dictionary, not a list to return JSON content.

import json

from django.http import HttpResponse

response_data = {}
response_data['result'] = 'error'
response_data['message'] = 'Some error message'

Pre-Django 1.7 you’d return it like this:

return HttpResponse(json.dumps(response_data), content_type="application/json")

For Django 1.7+, use JsonResponse as shown in this SO answer like so :

from django.http import JsonResponse
return JsonResponse({'foo':'bar'})

回答 1

Django 1.7的新功能

您可以使用JsonResponse对象。

从文档：

from django.http import JsonResponse
return JsonResponse({'foo':'bar'})

New in django 1.7

you could use JsonResponse objects.

from the docs:

from django.http import JsonResponse
return JsonResponse({'foo':'bar'})

回答 2

我用这个，很好用。

from django.utils import simplejson
from django.http import HttpResponse

def some_view(request):
    to_json = {
        "key1": "value1",
        "key2": "value2"
    }
    return HttpResponse(simplejson.dumps(to_json), mimetype='application/json')

选择：

from django.utils import simplejson

class JsonResponse(HttpResponse):
    """
        JSON response
    """
    def __init__(self, content, mimetype='application/json', status=None, content_type=None):
        super(JsonResponse, self).__init__(
            content=simplejson.dumps(content),
            mimetype=mimetype,
            status=status,
            content_type=content_type,
        )

在Django 1.7中，JsonResponse对象已添加到Django框架本身，这使此任务更加容易：

from django.http import JsonResponse
def some_view(request):
    return JsonResponse({"key": "value"})

I use this, it works fine.

from django.utils import simplejson
from django.http import HttpResponse

def some_view(request):
    to_json = {
        "key1": "value1",
        "key2": "value2"
    }
    return HttpResponse(simplejson.dumps(to_json), mimetype='application/json')

Alternative:

from django.utils import simplejson

class JsonResponse(HttpResponse):
    """
        JSON response
    """
    def __init__(self, content, mimetype='application/json', status=None, content_type=None):
        super(JsonResponse, self).__init__(
            content=simplejson.dumps(content),
            mimetype=mimetype,
            status=status,
            content_type=content_type,
        )

In Django 1.7 JsonResponse objects have been added to the Django framework itself which makes this task even easier:

from django.http import JsonResponse
def some_view(request):
    return JsonResponse({"key": "value"})

回答 3

从Django 1.7开始，您便拥有了所需的标准JsonResponse：

from django.http import JsonResponse
...
return JsonResponse(array_to_js, safe=False)

您甚至不需要json.dump您的数组。

Since Django 1.7 you have a standard JsonResponse that’s exactly what you need:

from django.http import JsonResponse
...
return JsonResponse(array_to_js, safe=False)

You don’t even need to json.dump your array.

回答 4

from django.http import HttpResponse
import json

class JsonResponse(HttpResponse):
    def __init__(self, content={}, mimetype=None, status=None,
             content_type='application/json'):
        super(JsonResponse, self).__init__(json.dumps(content), mimetype=mimetype,
                                           status=status, content_type=content_type)

并在视图中：

resp_data = {'my_key': 'my value',}
return JsonResponse(resp_data)

from django.http import HttpResponse
import json

class JsonResponse(HttpResponse):
    def __init__(self, content={}, mimetype=None, status=None,
             content_type='application/json'):
        super(JsonResponse, self).__init__(json.dumps(content), mimetype=mimetype,
                                           status=status, content_type=content_type)

And in the view:

resp_data = {'my_key': 'my value',}
return JsonResponse(resp_data)

回答 5

对于使用Django 1.7+的用户

from django.http import JsonResponse

def your_view(request):
    json_object = {'key': "value"}
    return JsonResponse(json_object)

官方文档

For those who use Django 1.7+

from django.http import JsonResponse

def your_view(request):
    json_object = {'key': "value"}
    return JsonResponse(json_object)

official docs

回答 6

您将要使用django序列化程序来帮助处理unicode内容：

from django.core import serializers

json_serializer = serializers.get_serializer("json")()
    response =  json_serializer.serialize(list, ensure_ascii=False, indent=2, use_natural_keys=True)
    return HttpResponse(response, mimetype="application/json")

You’ll want to use the django serializer to help with unicode stuff:

from django.core import serializers

json_serializer = serializers.get_serializer("json")()
    response =  json_serializer.serialize(list, ensure_ascii=False, indent=2, use_natural_keys=True)
    return HttpResponse(response, mimetype="application/json")

回答 7

使用基于Django类的视图，您可以编写：

from django.views import View
from django.http import JsonResponse

class JsonView(View):
    def get(self, request):
        return JsonResponse({'some': 'data'})

并使用Django-Rest-Framework可以编写：

from rest_framework.views import APIView
from rest_framework.response import Response

class JsonView(APIView):
    def get(self, request):
        return Response({'some': 'data'})

With Django Class-based views you can write:

from django.views import View
from django.http import JsonResponse

class JsonView(View):
    def get(self, request):
        return JsonResponse({'some': 'data'})

and with Django-Rest-Framework you can write:

from rest_framework.views import APIView
from rest_framework.response import Response

class JsonView(APIView):
    def get(self, request):
        return Response({'some': 'data'})

回答 8

对于Django 1.7或更高版本，使用JsonResponse类非常方便，因为它是HttpResponse的子类。

from django.http import JsonResponse
    def profile(request):
        data = {
            'name': 'Raghav',
            'location': 'India',
            'is_active': False,
            'count': 28
        }
        return JsonResponse(data)

对于旧版本的Django，您必须使用HttpResponse对象。

import json
from django.http import HttpResponse

def profile(request):
    data = {
        'name': 'Raghav',
        'location': 'India',
        'is_active': False,
        'count': 28
    }
    dump = json.dumps(data)
    return HttpResponse(dump, content_type='application/json')

Its very convenient with Django version 1.7 or higher as you have the JsonResponse class, which is a subclass of HttpResponse.

from django.http import JsonResponse
    def profile(request):
        data = {
            'name': 'Raghav',
            'location': 'India',
            'is_active': False,
            'count': 28
        }
        return JsonResponse(data)

For older versions of Django, you must use an HttpResponse object.

import json
from django.http import HttpResponse

def profile(request):
    data = {
        'name': 'Raghav',
        'location': 'India',
        'is_active': False,
        'count': 28
    }
    dump = json.dumps(data)
    return HttpResponse(dump, content_type='application/json')

回答 9

如何在Ajax（json）中使用Google App Engine？

使用JQuery的代码Javascript：

$.ajax({
    url: '/ajax',
    dataType : 'json',
    cache: false,
    success: function(data) {
        alert('Load was performed.'+data.ajax_resp);
    }
});

程式码Python

class Ajax(webapp2.RequestHandler):
    def get(self):
        my_response = {'ajax_resp':'Hello, webapp World!'}
        datos = json.dumps(my_response)

        self.response.headers.add_header('content-type', 'application/json', charset='utf-8')
        self.response.out.write(datos)

How to use google app engine with ajax (json)?

Code Javascript with JQuery:

$.ajax({
    url: '/ajax',
    dataType : 'json',
    cache: false,
    success: function(data) {
        alert('Load was performed.'+data.ajax_resp);
    }
});

Code Python

class Ajax(webapp2.RequestHandler):
    def get(self):
        my_response = {'ajax_resp':'Hello, webapp World!'}
        datos = json.dumps(my_response)

        self.response.headers.add_header('content-type', 'application/json', charset='utf-8')
        self.response.out.write(datos)

回答 10

这是使用基于类的视图的首选版本。只需将基本View子类化并覆盖get（）方法。

import json

class MyJsonView(View):

    def get(self, *args, **kwargs):
        resp = {'my_key': 'my value',}
        return HttpResponse(json.dumps(resp), mimetype="application/json" )

This is my preferred version using a class based view. Simply subclass the basic View and override the get()-method.

import json

class MyJsonView(View):

    def get(self, *args, **kwargs):
        resp = {'my_key': 'my value',}
        return HttpResponse(json.dumps(resp), mimetype="application/json" )

回答 11

Django代码views.py：

def view(request):
    if request.method == 'POST':
        print request.body
        data = request.body
        return HttpResponse(json.dumps(data))

HTML代码view.html：

<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
    $("#mySelect").change(function(){
        selected = $("#mySelect option:selected").text()
        $.ajax({
            type: 'POST',
            dataType: 'json',
            contentType: 'application/json; charset=utf-8',
            url: '/view/',
            data: {
                    'fruit': selected
                  },
            success: function(result) {
                        document.write(result)
                    }
    });
  });
});
</script>
</head>
<body>

<form>
    {{data}}
    <br>
Select your favorite fruit:
<select id="mySelect">
  <option value="apple" selected >Select fruit</option>
  <option value="apple">Apple</option>
  <option value="orange">Orange</option>
  <option value="pineapple">Pineapple</option>
  <option value="banana">Banana</option>
</select>
</form>
</body>
</html>

Django code views.py:

def view(request):
    if request.method == 'POST':
        print request.body
        data = request.body
        return HttpResponse(json.dumps(data))

HTML code view.html:

<!DOCTYPE html>
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script>
$(document).ready(function(){
    $("#mySelect").change(function(){
        selected = $("#mySelect option:selected").text()
        $.ajax({
            type: 'POST',
            dataType: 'json',
            contentType: 'application/json; charset=utf-8',
            url: '/view/',
            data: {
                    'fruit': selected
                  },
            success: function(result) {
                        document.write(result)
                    }
    });
  });
});
</script>
</head>
<body>

<form>
    {{data}}
    <br>
Select your favorite fruit:
<select id="mySelect">
  <option value="apple" selected >Select fruit</option>
  <option value="apple">Apple</option>
  <option value="orange">Orange</option>
  <option value="pineapple">Pineapple</option>
  <option value="banana">Banana</option>
</select>
</form>
</body>
</html>

回答 12

首先导入：

from django.http import HttpResponse

如果您已经有了JSON：

def your_method(request):
    your_json = [{'key1': value, 'key2': value}]
    return HttpResponse(your_json, 'application/json')

如果您从另一个HTTP请求获取JSON：

def your_method(request):
    response = request.get('https://www.example.com/get/json')
    return HttpResponse(response, 'application/json')

First import this:

from django.http import HttpResponse

If you have the JSON already:

def your_method(request):
    your_json = [{'key1': value, 'key2': value}]
    return HttpResponse(your_json, 'application/json')

If you get the JSON from another HTTP request:

def your_method(request):
    response = request.get('https://www.example.com/get/json')
    return HttpResponse(response, 'application/json')

回答 13

使用JsonResponse

from django.http import JsonResponse

Use JsonResponse

from django.http import JsonResponse

回答 14

在View中使用以下命令：

form.field.errors|striptags

用于获取没有html的验证消息

In View use this:

form.field.errors|striptags

for getting validation messages without html

知识问答

我可以将JSON加载到OrderedDict吗？

2021年7月25日 Python实用宝典

问题：我可以将JSON加载到OrderedDict吗？

好的，所以我可以在中使用OrderedDict json.dump。也就是说，OrderedDict可以用作JSON的输入。

但是可以用作输出吗？如果可以，怎么办？就我而言，我想load放入OrderedDict，以便可以将键的顺序保留在文件中。

如果没有，是否有某种解决方法？

Ok so I can use an OrderedDict in json.dump. That is, an OrderedDict can be used as an input to JSON.

But can it be used as an output? If so how? In my case I’d like to load into an OrderedDict so I can keep the order of the keys in the file.

If not, is there some kind of workaround?

回答 0

是的你可以。通过指定JSONDecoder的object_pairs_hook参数。实际上，这是文档中给出的确切示例。

>>> json.JSONDecoder(object_pairs_hook=collections.OrderedDict).decode('{"foo":1, "bar": 2}')
OrderedDict([('foo', 1), ('bar', 2)])
>>>

您可以将此参数传递给json.loads（如果不需要出于其他目的的Decoder实例），如下所示：

>>> import json
>>> from collections import OrderedDict
>>> data = json.loads('{"foo":1, "bar": 2}', object_pairs_hook=OrderedDict)
>>> print json.dumps(data, indent=4)
{
    "foo": 1,
    "bar": 2
}
>>>

使用json.load以相同的方式完成：

>>> data = json.load(open('config.json'), object_pairs_hook=OrderedDict)

Yes, you can. By specifying the object_pairs_hook argument to JSONDecoder. In fact, this is the exact example given in the documentation.

>>> json.JSONDecoder(object_pairs_hook=collections.OrderedDict).decode('{"foo":1, "bar": 2}')
OrderedDict([('foo', 1), ('bar', 2)])
>>>

You can pass this parameter to json.loads (if you don’t need a Decoder instance for other purposes) like so:

>>> import json
>>> from collections import OrderedDict
>>> data = json.loads('{"foo":1, "bar": 2}', object_pairs_hook=OrderedDict)
>>> print json.dumps(data, indent=4)
{
    "foo": 1,
    "bar": 2
}
>>>

Using json.load is done in the same way:

>>> data = json.load(open('config.json'), object_pairs_hook=OrderedDict)

回答 1

适用于Python 2.7+的简单版本

my_ordered_dict = json.loads(json_str, object_pairs_hook=collections.OrderedDict)

或适用于Python 2.4至2.6

import simplejson as json
import ordereddict

my_ordered_dict = json.loads(json_str, object_pairs_hook=ordereddict.OrderedDict)

Simple version for Python 2.7+

my_ordered_dict = json.loads(json_str, object_pairs_hook=collections.OrderedDict)

Or for Python 2.4 to 2.6

import simplejson as json
import ordereddict

my_ordered_dict = json.loads(json_str, object_pairs_hook=ordereddict.OrderedDict)

回答 2

一些好消息！从3.6版开始，cPython实现保留了字典的插入顺序（https://mail.python.org/pipermail/python-dev/2016-September/146327.html）。这意味着json库现在默认保留顺序。观察python 3.5和3.6之间的行为差异。编码：

import json
data = json.loads('{"foo":1, "bar":2, "fiddle":{"bar":2, "foo":1}}')
print(json.dumps(data, indent=4))

在py3.5中，结果顺序是不确定的：

{
    "fiddle": {
        "bar": 2,
        "foo": 1
    },
    "bar": 2,
    "foo": 1
}

在python 3.6的cPython实现中：

{
    "foo": 1,
    "bar": 2,
    "fiddle": {
        "bar": 2,
        "foo": 1
    }
}

真正的好消息是，这已成为python 3.7的语言规范（与cPython 3.6+的实现细节相反）：https ://mail.python.org/pipermail/python-dev/2017-December/151283 .html

因此，您的问题的答案现在变成：升级到python 3.6！:)

Some great news! Since version 3.6 the cPython implementation has preserved the insertion order of dictionaries (https://mail.python.org/pipermail/python-dev/2016-September/146327.html). This means that the json library is now order preserving by default. Observe the difference in behaviour between python 3.5 and 3.6. The code:

import json
data = json.loads('{"foo":1, "bar":2, "fiddle":{"bar":2, "foo":1}}')
print(json.dumps(data, indent=4))

In py3.5 the resulting order is undefined:

{
    "fiddle": {
        "bar": 2,
        "foo": 1
    },
    "bar": 2,
    "foo": 1
}

In the cPython implementation of python 3.6:

{
    "foo": 1,
    "bar": 2,
    "fiddle": {
        "bar": 2,
        "foo": 1
    }
}

The really great news is that this has become a language specification as of python 3.7 (as opposed to an implementation detail of cPython 3.6+): https://mail.python.org/pipermail/python-dev/2017-December/151283.html

So the answer to your question now becomes: upgrade to python 3.6! :)

回答 3

除了转储字典，您总是可以写出密钥列表，然后OrderedDict通过遍历列表来重建密钥？

You could always write out the list of keys in addition to dumping the dict, and then reconstruct the OrderedDict by iterating through the list?

回答 4

除了在字典旁边转储键的有序列表之外，另一种具有显式优点的低技术解决方案是转储键-值对的（有序）列表ordered_dict.items()。加载很简单OrderedDict(<list of key-value pairs>)。尽管JSON没有这个概念（JSON字典没有顺序），但这仍然可以处理有序字典。

利用json以正确顺序转储OrderedDict 的事实确实很好。但是，通常必须将所有 JSON字典作为OrderedDict 读取（通过object_pairs_hook参数）是不必要的繁琐操作，也不一定有意义，因此仅显式转换必须排序的字典也是有意义的。

In addition to dumping the ordered list of keys alongside the dictionary, another low-tech solution, which has the advantage of being explicit, is to dump the (ordered) list of key-value pairs ordered_dict.items(); loading is a simple OrderedDict(<list of key-value pairs>). This handles an ordered dictionary despite the fact that JSON does not have this concept (JSON dictionaries have no order).

It is indeed nice to take advantage of the fact that json dumps the OrderedDict in the correct order. However, it is in general unnecessarily heavy and not necessarily meaningful to have to read all JSON dictionaries as an OrderedDict (through the object_pairs_hook argument), so an explicit conversion of only the dictionaries that must be ordered makes sense too.

回答 5

如果指定object_pairs_hook参数，则通常使用的load命令将起作用：

import json
from  collections import OrderedDict
with open('foo.json', 'r') as fp:
    metrics_types = json.load(fp, object_pairs_hook=OrderedDict)

The normally used load command will work if you specify the object_pairs_hook parameter:

import json
from  collections import OrderedDict
with open('foo.json', 'r') as fp:
    metrics_types = json.load(fp, object_pairs_hook=OrderedDict)

知识问答

使用Python将JSON字符串转换为dict

2021年7月25日 Python实用宝典

问题：使用Python将JSON字符串转换为dict

我对Python中的JSON感到有些困惑。在我看来，这就像是一本字典，因此我正在尝试这样做：

{
    "glossary":
    {
        "title": "example glossary",
        "GlossDiv":
        {
            "title": "S",
            "GlossList":
            {
                "GlossEntry":
                {
                    "ID": "SGML",
                    "SortAs": "SGML",
                    "GlossTerm": "Standard Generalized Markup Language",
                    "Acronym": "SGML",
                    "Abbrev": "ISO 8879:1986",
                    "GlossDef":
                    {
                        "para": "A meta-markup language, used to create markup languages such as DocBook.",
                        "GlossSeeAlso": ["GML", "XML"]
                    },
                    "GlossSee": "markup"
                }
            }
        }
    }
}

但是当我这样做时print dict(json)，它会给出一个错误。

如何将该字符串转换为结构，然后调用json["title"]以获得“示例词汇表”？

I’m a little bit confused with JSON in Python. To me, it seems like a dictionary, and for that reason I’m trying to do that:

{
    "glossary":
    {
        "title": "example glossary",
        "GlossDiv":
        {
            "title": "S",
            "GlossList":
            {
                "GlossEntry":
                {
                    "ID": "SGML",
                    "SortAs": "SGML",
                    "GlossTerm": "Standard Generalized Markup Language",
                    "Acronym": "SGML",
                    "Abbrev": "ISO 8879:1986",
                    "GlossDef":
                    {
                        "para": "A meta-markup language, used to create markup languages such as DocBook.",
                        "GlossSeeAlso": ["GML", "XML"]
                    },
                    "GlossSee": "markup"
                }
            }
        }
    }
}

But when I do print dict(json), it gives an error.

How can I transform this string into a structure and then call json["title"] to obtain “example glossary”?

回答 0

json.loads()

import json

d = json.loads(j)
print d['glossary']['title']

json.loads()

import json

d = json.loads(j)
print d['glossary']['title']

回答 1

当我开始使用json时，我很困惑，无法解决一段时间，但最终我得到了想要的东西。
这是简单的解决方案

import json
m = {'id': 2, 'name': 'hussain'}
n = json.dumps(m)
o = json.loads(n)
print(o['id'], o['name'])

When I started using json, I was confused and unable to figure it out for some time, but finally I got what I wanted
Here is the simple solution

import json
m = {'id': 2, 'name': 'hussain'}
n = json.dumps(m)
o = json.loads(n)
print(o['id'], o['name'])

回答 2

使用simplejson或cjson进行加速

import simplejson as json

json.loads(obj)

or 

cjson.decode(obj)

use simplejson or cjson for speedups

import simplejson as json

json.loads(obj)

or 

cjson.decode(obj)

回答 3

如果您信任数据源，则可以用于eval将字符串转换为字典：

eval(your_json_format_string)

例：

>>> x = "{'a' : 1, 'b' : True, 'c' : 'C'}"
>>> y = eval(x)

>>> print x
{'a' : 1, 'b' : True, 'c' : 'C'}
>>> print y
{'a': 1, 'c': 'C', 'b': True}

>>> print type(x), type(y)
<type 'str'> <type 'dict'>

>>> print y['a'], type(y['a'])
1 <type 'int'>

>>> print y['a'], type(y['b'])
1 <type 'bool'>

>>> print y['a'], type(y['c'])
1 <type 'str'>

If you trust the data source, you can use eval to convert your string into a dictionary:

eval(your_json_format_string)

Example:

>>> x = "{'a' : 1, 'b' : True, 'c' : 'C'}"
>>> y = eval(x)

>>> print x
{'a' : 1, 'b' : True, 'c' : 'C'}
>>> print y
{'a': 1, 'c': 'C', 'b': True}

>>> print type(x), type(y)
<type 'str'> <type 'dict'>

>>> print y['a'], type(y['a'])
1 <type 'int'>

>>> print y['a'], type(y['b'])
1 <type 'bool'>

>>> print y['a'], type(y['c'])
1 <type 'str'>

知识问答

Python和JavaScript之间的JSON日期时间

2021年7月25日 Python实用宝典

问题：Python和JavaScript之间的JSON日期时间

我想使用JSON从Python发送序列化形式的datetime.datetime对象，并使用JSON在JavaScript中反序列化。做这个的最好方式是什么？

I want to send a datetime.datetime object in serialized form from Python using JSON and de-serialize in JavaScript using JSON. What is the best way to do this?

回答 0

您可以在json.dumps中添加“默认”参数来处理此问题：

date_handler = lambda obj: (
    obj.isoformat()
    if isinstance(obj, (datetime.datetime, datetime.date))
    else None
)
json.dumps(datetime.datetime.now(), default=date_handler)
'"2010-04-20T20:08:21.634121"'

这是ISO 8601格式。

更全面的默认处理程序功能：

def handler(obj):
    if hasattr(obj, 'isoformat'):
        return obj.isoformat()
    elif isinstance(obj, ...):
        return ...
    else:
        raise TypeError, 'Object of type %s with value of %s is not JSON serializable' % (type(obj), repr(obj))

更新：添加了类型和值的输出。
更新：还处理日期

You can add the ‘default’ parameter to json.dumps to handle this:

date_handler = lambda obj: (
    obj.isoformat()
    if isinstance(obj, (datetime.datetime, datetime.date))
    else None
)
json.dumps(datetime.datetime.now(), default=date_handler)
'"2010-04-20T20:08:21.634121"'

Which is ISO 8601 format.

A more comprehensive default handler function:

def handler(obj):
    if hasattr(obj, 'isoformat'):
        return obj.isoformat()
    elif isinstance(obj, ...):
        return ...
    else:
        raise TypeError, 'Object of type %s with value of %s is not JSON serializable' % (type(obj), repr(obj))

Update: Added output of type as well as value.
Update: Also handle date

回答 1

对于跨语言项目，我发现包含RfC 3339日期的字符串是最好的选择。RfC 3339日期如下所示：

  1985-04-12T23:20:50.52Z

我认为大多数格式都是显而易见的。唯一有点不寻常的事情可能是结尾处的“ Z”。它代表GMT / UTC。您还可以为CEST添加夏令时偏移，例如+02：00（德国夏季）。我个人更喜欢将所有内容保留在UTC中，直到显示为止。

为了显示，比较和存储，您可以将其保留为所有语言的字符串格式。如果您需要日期进行计算，可以轻松将其转换为大多数语言的原始日期对象。

因此，生成这样的JSON：

  json.dump(datetime.now().strftime('%Y-%m-%dT%H:%M:%SZ'))

不幸的是，Javascript的Date构造函数不接受RfC 3339字符串，但是Internet上有很多解析器。

huTools.hujson会尝试处理Python代码中可能遇到的最常见的编码问题，包括日期/日期时间对象，同时正确处理时区。

For cross-language projects, I found out that strings containing RfC 3339 dates are the best way to go. An RfC 3339 date looks like this:

  1985-04-12T23:20:50.52Z

I think most of the format is obvious. The only somewhat unusual thing may be the “Z” at the end. It stands for GMT/UTC. You could also add a timezone offset like +02:00 for CEST (Germany in summer). I personally prefer to keep everything in UTC until it is displayed.

For displaying, comparisons and storage you can leave it in string format across all languages. If you need the date for calculations easy to convert it back to a native date object in most language.

So generate the JSON like this:

  json.dump(datetime.now().strftime('%Y-%m-%dT%H:%M:%SZ'))

Unfortunately, Javascript’s Date constructor doesn’t accept RfC 3339 strings but there are many parsers available on the Internet.

huTools.hujson tries to handle the most common encoding issues you might come across in Python code including date/datetime objects while handling timezones correctly.

回答 2

我已经解决了。

假设您有一个使用datetime.now（）创建的Python datetime对象d。其值为：

datetime.datetime(2011, 5, 25, 13, 34, 5, 787000)

您可以将其序列化为JSON作为ISO 8601日期时间字符串：

import json    
json.dumps(d.isoformat())

日期时间对象示例将序列化为：

'"2011-05-25T13:34:05.787000"'

一旦在Javascript层中收到此值，就可以构造一个Date对象：

var d = new Date("2011-05-25T13:34:05.787000");

从Javascript 1.8.5开始，Date对象具有toJSON方法，该方法返回标准格式的字符串。要将上述Javascript对象序列化回JSON，命令将是：

d.toJSON()

这会给你：

'2011-05-25T20:34:05.787Z'

一旦在Python中收到此字符串，就可以将其反序列化为datetime对象：

datetime.strptime('2011-05-25T20:34:05.787Z', '%Y-%m-%dT%H:%M:%S.%fZ')

这将导致以下日期时间对象，该对象与您开始时使用的对象相同，因此是正确的：

datetime.datetime(2011, 5, 25, 20, 34, 5, 787000)

I’ve worked it out.

Let’s say you have a Python datetime object, d, created with datetime.now(). Its value is:

datetime.datetime(2011, 5, 25, 13, 34, 5, 787000)

You can serialize it to JSON as an ISO 8601 datetime string:

import json    
json.dumps(d.isoformat())

The example datetime object would be serialized as:

'"2011-05-25T13:34:05.787000"'

This value, once received in the Javascript layer, can construct a Date object:

var d = new Date("2011-05-25T13:34:05.787000");

As of Javascript 1.8.5, Date objects have a toJSON method, which returns a string in a standard format. To serialize the above Javascript object back to JSON, therefore, the command would be:

d.toJSON()

Which would give you:

'2011-05-25T20:34:05.787Z'

This string, once received in Python, could be deserialized back to a datetime object:

datetime.strptime('2011-05-25T20:34:05.787Z', '%Y-%m-%dT%H:%M:%S.%fZ')

This results in the following datetime object, which is the same one you started with and therefore correct:

datetime.datetime(2011, 5, 25, 20, 34, 5, 787000)

回答 3

使用json，您可以子类化JSONEncoder并重写default（）方法以提供自己的自定义序列化程序：

import json
import datetime

class DateTimeJSONEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, datetime.datetime):
            return obj.isoformat()
        else:
            return super(DateTimeJSONEncoder, self).default(obj)

然后，您可以这样称呼它：

>>> DateTimeJSONEncoder().encode([datetime.datetime.now()])
'["2010-06-15T14:42:28"]'

Using json, you can subclass JSONEncoder and override the default() method to provide your own custom serializers:

import json
import datetime

class DateTimeJSONEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, datetime.datetime):
            return obj.isoformat()
        else:
            return super(DateTimeJSONEncoder, self).default(obj)

Then, you can call it like this:

>>> DateTimeJSONEncoder().encode([datetime.datetime.now()])
'["2010-06-15T14:42:28"]'

回答 4

这是一个使用标准库json模块递归编码和解码datetime.datetime和datetime.date对象的完整解决方案。此后需要Python> = 2.6，因为从那时起%f仅支持datetime.datetime.strptime（）格式字符串中的格式代码。对于Python 2.5支持，%f在尝试转换之前，请从ISO日期字符串中删除和除去微秒，但是，您当然会降低微秒的精度。为了与其他来源的ISO日期字符串互操作，其中可能包括时区名称或UTC偏移量，您可能还需要在转换之前剥离日期字符串的某些部分。有关ISO日期字符串（和许多其他日期格式）的完整解析器，请参见第三方dateutil模块。

仅当ISO日期字符串是JavaScript文字对象表示法中的值或对象中嵌套结构中的值时，才起作用。作为顶级数组项目的ISO日期字符串将不会被解码。

即这有效：

date = datetime.datetime.now()
>>> json = dumps(dict(foo='bar', innerdict=dict(date=date)))
>>> json
'{"innerdict": {"date": "2010-07-15T13:16:38.365579"}, "foo": "bar"}'
>>> loads(json)
{u'innerdict': {u'date': datetime.datetime(2010, 7, 15, 13, 16, 38, 365579)},
u'foo': u'bar'}

这也是：

>>> json = dumps(['foo', 'bar', dict(date=date)])
>>> json
'["foo", "bar", {"date": "2010-07-15T13:16:38.365579"}]'
>>> loads(json)
[u'foo', u'bar', {u'date': datetime.datetime(2010, 7, 15, 13, 16, 38, 365579)}]

但这不能按预期工作：

>>> json = dumps(['foo', 'bar', date])
>>> json
'["foo", "bar", "2010-07-15T13:16:38.365579"]'
>>> loads(json)
[u'foo', u'bar', u'2010-07-15T13:16:38.365579']

这是代码：

__all__ = ['dumps', 'loads']

import datetime

try:
    import json
except ImportError:
    import simplejson as json

class JSONDateTimeEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, (datetime.date, datetime.datetime)):
            return obj.isoformat()
        else:
            return json.JSONEncoder.default(self, obj)

def datetime_decoder(d):
    if isinstance(d, list):
        pairs = enumerate(d)
    elif isinstance(d, dict):
        pairs = d.items()
    result = []
    for k,v in pairs:
        if isinstance(v, basestring):
            try:
                # The %f format code is only supported in Python >= 2.6.
                # For Python <= 2.5 strip off microseconds
                # v = datetime.datetime.strptime(v.rsplit('.', 1)[0],
                #     '%Y-%m-%dT%H:%M:%S')
                v = datetime.datetime.strptime(v, '%Y-%m-%dT%H:%M:%S.%f')
            except ValueError:
                try:
                    v = datetime.datetime.strptime(v, '%Y-%m-%d').date()
                except ValueError:
                    pass
        elif isinstance(v, (dict, list)):
            v = datetime_decoder(v)
        result.append((k, v))
    if isinstance(d, list):
        return [x[1] for x in result]
    elif isinstance(d, dict):
        return dict(result)

def dumps(obj):
    return json.dumps(obj, cls=JSONDateTimeEncoder)

def loads(obj):
    return json.loads(obj, object_hook=datetime_decoder)

if __name__ == '__main__':
    mytimestamp = datetime.datetime.utcnow()
    mydate = datetime.date.today()
    data = dict(
        foo = 42,
        bar = [mytimestamp, mydate],
        date = mydate,
        timestamp = mytimestamp,
        struct = dict(
            date2 = mydate,
            timestamp2 = mytimestamp
        )
    )

    print repr(data)
    jsonstring = dumps(data)
    print jsonstring
    print repr(loads(jsonstring))

Here’s a fairly complete solution for recursively encoding and decoding datetime.datetime and datetime.date objects using the standard library json module. This needs Python >= 2.6 since the %f format code in the datetime.datetime.strptime() format string is only supported in since then. For Python 2.5 support, drop the %f and strip the microseconds from the ISO date string before trying to convert it, but you’ll loose microseconds precision, of course. For interoperability with ISO date strings from other sources, which may include a time zone name or UTC offset, you may also need to strip some parts of the date string before the conversion. For a complete parser for ISO date strings (and many other date formats) see the third-party dateutil module.

Decoding only works when the ISO date strings are values in a JavaScript literal object notation or in nested structures within an object. ISO date strings, which are items of a top-level array will not be decoded.

I.e. this works:

date = datetime.datetime.now()
>>> json = dumps(dict(foo='bar', innerdict=dict(date=date)))
>>> json
'{"innerdict": {"date": "2010-07-15T13:16:38.365579"}, "foo": "bar"}'
>>> loads(json)
{u'innerdict': {u'date': datetime.datetime(2010, 7, 15, 13, 16, 38, 365579)},
u'foo': u'bar'}

And this too:

>>> json = dumps(['foo', 'bar', dict(date=date)])
>>> json
'["foo", "bar", {"date": "2010-07-15T13:16:38.365579"}]'
>>> loads(json)
[u'foo', u'bar', {u'date': datetime.datetime(2010, 7, 15, 13, 16, 38, 365579)}]

But this doesn’t work as expected:

>>> json = dumps(['foo', 'bar', date])
>>> json
'["foo", "bar", "2010-07-15T13:16:38.365579"]'
>>> loads(json)
[u'foo', u'bar', u'2010-07-15T13:16:38.365579']

Here’s the code:

__all__ = ['dumps', 'loads']

import datetime

try:
    import json
except ImportError:
    import simplejson as json

class JSONDateTimeEncoder(json.JSONEncoder):
    def default(self, obj):
        if isinstance(obj, (datetime.date, datetime.datetime)):
            return obj.isoformat()
        else:
            return json.JSONEncoder.default(self, obj)

def datetime_decoder(d):
    if isinstance(d, list):
        pairs = enumerate(d)
    elif isinstance(d, dict):
        pairs = d.items()
    result = []
    for k,v in pairs:
        if isinstance(v, basestring):
            try:
                # The %f format code is only supported in Python >= 2.6.
                # For Python <= 2.5 strip off microseconds
                # v = datetime.datetime.strptime(v.rsplit('.', 1)[0],
                #     '%Y-%m-%dT%H:%M:%S')
                v = datetime.datetime.strptime(v, '%Y-%m-%dT%H:%M:%S.%f')
            except ValueError:
                try:
                    v = datetime.datetime.strptime(v, '%Y-%m-%d').date()
                except ValueError:
                    pass
        elif isinstance(v, (dict, list)):
            v = datetime_decoder(v)
        result.append((k, v))
    if isinstance(d, list):
        return [x[1] for x in result]
    elif isinstance(d, dict):
        return dict(result)

def dumps(obj):
    return json.dumps(obj, cls=JSONDateTimeEncoder)

def loads(obj):
    return json.loads(obj, object_hook=datetime_decoder)

if __name__ == '__main__':
    mytimestamp = datetime.datetime.utcnow()
    mydate = datetime.date.today()
    data = dict(
        foo = 42,
        bar = [mytimestamp, mydate],
        date = mydate,
        timestamp = mytimestamp,
        struct = dict(
            date2 = mydate,
            timestamp2 = mytimestamp
        )
    )

    print repr(data)
    jsonstring = dumps(data)
    print jsonstring
    print repr(loads(jsonstring))

回答 5

如果您确定只有Javascript将使用JSON，则我更喜欢Date直接传递Javascript 对象。

对象ctime()上的方法datetime将返回Javascript Date对象可以理解的字符串。

import datetime
date = datetime.datetime.today()
json = '{"mydate":new Date("%s")}' % date.ctime()

Javascript将很乐意将其用作对象文字，并且您已经内置了Date对象。

If you’re certain that only Javascript will be consuming the JSON, I prefer to pass Javascript Date objects directly.

The ctime() method on datetime objects will return a string that the Javascript Date object can understand.

import datetime
date = datetime.datetime.today()
json = '{"mydate":new Date("%s")}' % date.ctime()

Javascript will happily use that as an object literal, and you’ve got your Date object built right in.

回答 6

比赛后期… :)

一个非常简单的解决方案是修补json模块的默认值。例如：

import json
import datetime

json.JSONEncoder.default = lambda self,obj: (obj.isoformat() if isinstance(obj, datetime.datetime) else None)

现在，您可以使用json.dumps（），就好像它一直支持日期时间一样。

json.dumps({'created':datetime.datetime.now()})

如果您需要始终对json模块进行此扩展，并且希望不更改您或其他人使用json序列化的方式（无论是否使用现有代码），则这是有道理的。

请注意，有些人可能认为以这种方式对库进行修补是不好的做法。如果您可能希望以多种方式扩展应用程序，则需要格外小心-在这种情况下，我建议使用ramen或JT解决方案，并在每种情况下选择合适的json扩展名。

Late in the game… :)

A very simple solution is to patch the json module default. For example:

import json
import datetime

json.JSONEncoder.default = lambda self,obj: (obj.isoformat() if isinstance(obj, datetime.datetime) else None)

Now, you can use json.dumps() as if it had always supported datetime…

json.dumps({'created':datetime.datetime.now()})

This makes sense if you require this extension to the json module to always kick in and wish to not change the way you or others use json serialization (either in existing code or not).

Note that some may consider patching libraries in that way as bad practice. Special care need to be taken in case you may wish to extend your application in more than one way – is such a case, I suggest to use the solution by ramen or JT and choose the proper json extension in each case.

回答 7

除了时间戳，没有什么可添加到社区Wiki答案中了！

Javascript使用以下格式：

new Date().toJSON() // "2016-01-08T19:00:00.123Z"

Python端（有关json.dumps处理程序，请参见其他答案）：

>>> from datetime import datetime
>>> d = datetime.strptime('2016-01-08T19:00:00.123Z', '%Y-%m-%dT%H:%M:%S.%fZ')
>>> d
datetime.datetime(2016, 1, 8, 19, 0, 0, 123000)
>>> d.isoformat() + 'Z'
'2016-01-08T19:00:00.123000Z'

如果将Z保留在外，那么诸如angular的前端框架将无法在浏览器本地时区中显示日期：

> $filter('date')('2016-01-08T19:00:00.123000Z', 'yyyy-MM-dd HH:mm:ss')
"2016-01-08 20:00:00"
> $filter('date')('2016-01-08T19:00:00.123000', 'yyyy-MM-dd HH:mm:ss')
"2016-01-08 19:00:00"

Not much to add to the community wiki answer, except for timestamp!

Javascript uses the following format:

new Date().toJSON() // "2016-01-08T19:00:00.123Z"

Python side (for the json.dumps handler, see the other answers):

>>> from datetime import datetime
>>> d = datetime.strptime('2016-01-08T19:00:00.123Z', '%Y-%m-%dT%H:%M:%S.%fZ')
>>> d
datetime.datetime(2016, 1, 8, 19, 0, 0, 123000)
>>> d.isoformat() + 'Z'
'2016-01-08T19:00:00.123000Z'

If you leave that Z out, frontend frameworks like angular can not display the date in browser-local timezone:

> $filter('date')('2016-01-08T19:00:00.123000Z', 'yyyy-MM-dd HH:mm:ss')
"2016-01-08 20:00:00"
> $filter('date')('2016-01-08T19:00:00.123000', 'yyyy-MM-dd HH:mm:ss')
"2016-01-08 19:00:00"

回答 8

在python方面：

import time, json
from datetime import datetime as dt
your_date = dt.now()
data = json.dumps(time.mktime(your_date.timetuple())*1000)
return data # data send to javascript

在JavaScript方面：

var your_date = new Date(data)

数据来自python的地方

On python side:

import time, json
from datetime import datetime as dt
your_date = dt.now()
data = json.dumps(time.mktime(your_date.timetuple())*1000)
return data # data send to javascript

On javascript side:

var your_date = new Date(data)

where data is result from python

回答 9

我的建议是使用一个库。pypi.org上有几个可用的。

我使用这个，它很好用：https : //pypi.python.org/pypi/asjson

My advice is to use a library. There are several available at pypi.org.

I use this one, it it works good: https://pypi.python.org/pypi/asjson

回答 10

显然，“正确的” JSON（很好的JavaScript）日期格式是2012-04-23T18：25：43.511Z-UTC和“ Z”。如果没有此功能，则从字符串创建Date（）对象时，JavaScript将使用Web浏览器的本地时区。

对于“天真的”时间（Python称没有时区的时间，并且假定是本地时间），以下内容将强制使用本地时区，以便随后可以将其正确转换为UTC：

def default(obj):
    if hasattr(obj, "json") and callable(getattr(obj, "json")):
        return obj.json()
    if hasattr(obj, "isoformat") and callable(getattr(obj, "isoformat")):
        # date/time objects
        if not obj.utcoffset():
            # add local timezone to "naive" local time
            # /programming/2720319/python-figure-out-local-timezone
            tzinfo = datetime.now(timezone.utc).astimezone().tzinfo
            obj = obj.replace(tzinfo=tzinfo)
        # convert to UTC
        obj = obj.astimezone(timezone.utc)
        # strip the UTC offset
        obj = obj.replace(tzinfo=None)
        return obj.isoformat() + "Z"
    elif hasattr(obj, "__str__") and callable(getattr(obj, "__str__")):
        return str(obj)
    else:
        print("obj:", obj)
        raise TypeError(obj)

def dump(j, io):
    json.dump(j, io, indent=2, default=default)

为什么这么难。

Apparently The “right” JSON (well JavaScript) date format is 2012-04-23T18:25:43.511Z – UTC and “Z”. Without this JavaScript will use the web browser’s local timezone when creating a Date() object from the string.

For a “naive” time (what Python calls a time with no timezone and this assumes is local) the below will force local timezone so that it can then be correctly converted to UTC:

def default(obj):
    if hasattr(obj, "json") and callable(getattr(obj, "json")):
        return obj.json()
    if hasattr(obj, "isoformat") and callable(getattr(obj, "isoformat")):
        # date/time objects
        if not obj.utcoffset():
            # add local timezone to "naive" local time
            # https://stackoverflow.com/questions/2720319/python-figure-out-local-timezone
            tzinfo = datetime.now(timezone.utc).astimezone().tzinfo
            obj = obj.replace(tzinfo=tzinfo)
        # convert to UTC
        obj = obj.astimezone(timezone.utc)
        # strip the UTC offset
        obj = obj.replace(tzinfo=None)
        return obj.isoformat() + "Z"
    elif hasattr(obj, "__str__") and callable(getattr(obj, "__str__")):
        return str(obj)
    else:
        print("obj:", obj)
        raise TypeError(obj)

def dump(j, io):
    json.dump(j, io, indent=2, default=default)

why is this so hard.

回答 11

对于从Python到JavaScript的日期转换，日期对象必须采用特定的ISO格式，即ISO格式或UNIX数字。如果ISO格式缺少某些信息，则可以先使用Date.parse转换为Unix数字。此外，Date.parse也可以与React一起使用，而新的Date可能会触发异常。

如果您有一个不带毫秒的DateTime对象，则需要考虑以下因素。：

  var unixDate = Date.parse('2016-01-08T19:00:00') 
  var desiredDate = new Date(unixDate).toLocaleDateString();

在API调用之后，示例日期也可以是result.data对象中的变量。

有关以所需格式显示日期的选项（例如，显示较长的工作日），请查看MDN文档。

For the Python to JavaScript date conversion, the date object needs to be in specific ISO format, i.e. ISO format or UNIX number. If the ISO format lacks some info, then you can convert to the Unix number with Date.parse first. Moreover, Date.parse works with React as well while new Date might trigger an exception.

In case you have a DateTime object without milliseconds, the following needs to be considered. :

  var unixDate = Date.parse('2016-01-08T19:00:00') 
  var desiredDate = new Date(unixDate).toLocaleDateString();

The example date could equally be a variable in the result.data object after an API call.

For options to display the date in the desired format (e.g. to display long weekdays) check out the MDN doc.