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How to make simplejson serializable class

I have a class defined like this

class A:
    def __init__(self):
        self.item1 = None
    def __repr__(self):
        return str(self.__dict__)

when I do:

>>> import simplejson
>>> myA = A()
>>> simplejson.dumps(myA)
TypeError: {'item1': None} is not JSON serializable

I can't find the reason why.

Do I need to add any particular method to A for simplejson to serialize my class object?

Using Python simplejson to return pregenerated json

I have a GeoDjango model object that I want't to serialize to json. I do this in my view:

lat = float(request.GET.get('lat'))
lng = float(request.GET.get('lng'))
a = Authority.objects.get(area__contains=Point(lng, lat))
if a:
    return HttpResponse(simplejson.dumps({'name': a.name, 
                                          'area': a.area.geojson,
                                          'id': a.id}), 
                        mimetype='application/json')

The problem is that simplejson considers the a.area.geojson as a simple string, even though it is beautiful pre-generated json. This is easily fixed in the client by eval()'ing the area-string, but I would like to do it proper. Can I tell simplejson that a particular string is already json and should be used as-is (and not returned as a simple string)? Or is there another workaround?

UPDATE Just to clarify, this is the json currently returned:

{
    "id": 95,
    "name": "Roskilde",
    "area": "{ \"type\": \"MultiPolygon\", \"coordinates\": [ [ [ [ 12.078701, 55.649927 ], ... ] ] ] }"
}

The challenge is to have "area" be a json dictionary instead of a simple string.

Google Data Source JSON not valid?

I am implementing a Google Data Source using their Python Library. I would like the response from the library to be able to be imported in another Python script using the simplejson library.

However, even their example doesn't validate in JSONLint:

{cols: 
    [{id:'name',label:'Name',type:'string'},
     {id:'salary',label:'Salary',type:'number'},
     {id:'full_time',label:'Full Time Employee',type:'boolean'}],
rows: 
    [{c:[{v:'Jim'},{v:800,f:'$800'},{v:false}]},
     {c:[{v:'Bob'},{v:7000,f:'$7,000'},{v:true}]},
     {c:[{v:'Mike'},{v:10000,f:'$10,000'},{v:true}]},
     {c:[{v:'Alice'},{v:12500,f:'$12,500'},{v:true}]}]}

How do I tweak the simplejson 'loads' function to import the above JSON? I think the main problem is that the object keys are not strings.

I would rather not write a regex to convert the keys to strings since I think such code would be annoying to maintain.

I am currently getting an "Expecting property name: line 1 column 1 (char 1)" error when trying to import the above json into python with simplejson.

simplejson.loads() get Invalid \escape: 'x'

I am learning how to use simplejson to decode JSON file. But I suffered the "invalid \escape" error. Here is the code

import simplejson as json

def main():
    json.loads(r'{"test":"\x27"}')

if __name__ == '__main__':
    main()

And here is the error message

Traceback (most recent call last):
  File "hello_world.py", line 7, in <module>
    main()
  File "hello_world.py", line 4, in main
    json.loads(r'{"test":"\x27"}')
  File "C:\Users\zhangkai\python\simplejson\__init__.py", line 307, in loads
    return _default_decoder.decode(s)
  File "C:\Users\zhangkai\python\simplejson\decoder.py", line 335, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "C:\Users\zhangkai\python\simplejson\decoder.py", line 351, in raw_decode

    obj, end = self.scan_once(s, idx)
  File "C:\Users\zhangkai\python\simplejson\scanner.py", line 36, in _scan_once
    return parse_object((string, idx + 1), encoding, strict, _scan_once, object_
hook)
  File "C:\Users\zhangkai\python\simplejson\decoder.py", line 185, in JSONObject

    value, end = scan_once(s, end)
  File "C:\Users\zhangkai\python\simplejson\scanner.py", line 34, in _scan_once
    return parse_string(string, idx + 1, encoding, strict)
  File "C:\Users\zhangkai\python\simplejson\decoder.py", line 114, in py_scanstr
ing
    raise ValueError(errmsg(msg, s, end))
ValueError: Invalid \escape: 'x': line 1 column 10 (char 10)

I think json parser is supposed to recognize the escape. So I want to know what is wrong, and what should I do.

How to serialize db.Model objects to json?

When using

from django.utils import simplejson

on objects of types that derive from db.Model it throws exceptions. How to circumvent this?

Decode complex JSON in Python

Hey, I have a JSON object created in PHP, that JSON object contains another escaped JSON string in one of it's cells:

php > $insidejson = array('foo' => 'bar','foo1' => 'bar1');
php > $arr = array('a' => array('a1'=>json_encode($insidejson)));
php > echo json_encode($arr);
{"a":{"a1":"{\"foo\":\"bar\",\"foo1\":\"bar1\"}"}}

Then, with Python, I try deocding it using simplejson:

>>> import simplejson as json
>>> json.loads('{"a":{"a1":"{\"foo\":\"bar\",\"foo1\":\"bar1\"}"}}')

This fails with the following error:

Traceback (most recent call last):
  File "", line 1, in ?
  File "build/bdist.linux-i686/egg/simplejson/__init__.py", line 307, in loads
  File "build/bdist.linux-i686/egg/simplejson/decoder.py", line 335, in decode
  File "build/bdist.linux-i686/egg/simplejson/decoder.py", line 351, in raw_decode
ValueError: Expecting , delimiter: line 1 column 14 (char 14)

How can I get this JSON object decoded in Python? Both PHP and JS decode it successfully and I can't change it's structure since that would require major changes in many different components in different languages.

Thanks!

How to solve the ImportError: cannot import name simplejson in Django

I'm trying to build a realtime chat app in Django(1.7.1). It seems that I needed to install Redis and ishout.js. So I installed them by following the instructions.

After making the project in Django, I put 'drealtime' under the INSTALLED_APPS, and put:

'drealtime.middleware.iShoutCookieMiddleware' 

right above :

'django.contrib.sessions.middleware.SessionMiddleware' 

under the MIDDLEWARE_CLASSES as it was saying. And I put the command like

python manage.py startapp example

but still I have this import error message:

Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/core/management/__init__.py", line 385, in execute_from_command_line
    utility.execute()
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/core/management/__init__.py", line 354, in execute
    django.setup()
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/__init__.py", line 21, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/apps/registry.py", line 85, in populate
    app_config = AppConfig.create(entry)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/django/apps/config.py", line 87, in create
    module = import_module(entry)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/drealtime/__init__.py", line 4, in <module>
    from django.utils import simplejson as json

After I searched through the Django official site, I found simplejson is no longer used and removed from new Django. I don't know why this is happening. Please give any feedback on this issue and possible remedy to tackle this issue.

Python: Convert simplejson dumped unicode datetime back to datetime object

I have...

entity = simplejson.dumps({"a":unicode(datetime.datetime.utcnow())})

How do I convert the datetime (that was converted to unicode) back to datetime again?

So that I can do something like...

entity2 = simplejson.loads(entity)
#your answer here..
add5 = entity2["a"] + datetime.timedelta(minutes=5)

Thanks!

XML library similar to simplejson/json? - Python

is there a similar library to simplejson, which would enable quick serialization of data to and from XML.

e.g. json.loads('{vol:'III', title:'Magical Unicorn'}')

e.g. json.dumps([1,2,3,4,5])

Any ideas?

Is there any way to make simplejson less strict?

I'm interested in having simplejson.loads() successfully parse the following:

{foo:3}

It throws JSONDecodeError saying "expecting property name" but in reality it's saying "I require double quotes around my property names". This is annoying for my use case, and I'd prefer a less strict behavior. I've read the docs, but beyond making my own decoder class, I don't see anything obvious that changes this behavior.

Flask Jsonify mongoengine query

I have method like this , and want to return as Json , but it writes that Posts object is not Json serializable :S

def show_results_async(text):
   query  =  { '$or':[{'title':{'$regex':text}},{'author':{'$regex':text}} ]}
   posts = Posts.objects(__raw__=(query))
   return jsonify(result = posts)

Single versus double quotes in json loads in Python

I notice that single quotes cause simplejson's loads function to fail:

>>> import simplejson as json
>>> json.loads("\"foo\"")
'foo'
>>> json.loads("\'foo\'")
Traceback (most recent call last):
...
ValueError: No JSON object could be decoded

I'm parsing things like: foo = ["a", "b", "c"] from a textfile into lists in Python and would like to also accept foo = ['a', 'b', 'c']. simplejson is convenient for making foo automatically into a list.

How can I get loads to accept single quotes, or automatically substitute double for single quotes without wrecking the input? thanks.

installing simplejson on the google appengine

Super nub question time! I am trying to use simplejson on the google appengine. In a terminal on my machine I have simplejson installed and working. But my when I try to import it in a script running on the appengine I get an error saying no such library exists. If open the interactive console on my machine (from the link on http://localhost:8080/_ah/admin) and type "import simplejson" I get:

Traceback (most recent call last): File "/home/chris/google_appengine/google/appengine/ext/admin/init.py", line 210, in post exec(compiled_code, globals()) File "", line 1, in ImportError: No module named simplejson

Any thoughts?

How to ensure that a python dict keys are lowercase?

I have a dict that I want to convert in JSON using simplejson.

How can I ensure that all the keys of my dict are lowercase ?

    {
        "DISTANCE": 17.059918745802999, 
        "name": "Foo Bar", 
        "Restaurant": {
            "name": "Foo Bar", 
            "full_address": {
                "country": "France", 
                "street": "Foo Bar", 
                "zip_code": "68190", 
                "city": "UNGERSHEIM"
            }, 
            "phone": "+33.389624300", 
            "longitude": "7.3064454", 
            "latitude": "47.8769091", 
            "id": "538"
        }, 
        "price": "", 
        "composition": "", 
        "profils": {}, 
        "type_menu": "", 
        "ID": ""
    },

EDIT: Thanks all to had a look at my question, I am sorry I didn't explain in detailed why I wanted this. It was to patch the JSONEmitter of django-piston.

django escapejs and simplejson

I'm trying to encode a Python array into json using simplejson.dumps:

In [30]: s1 = ['test', '<script>']

In [31]: simplejson.dumps(s1)
Out[31]: '["test", "<script>"]'

Works fine.

But I want to escape the strings first (using escapejs from Django) before calling simplejson.dumps:

In [35]: s_esc
Out[35]: [u'test', u'\\u003Cscript\\u003E']

In [36]: print simplejson.dumps(s_esc)
["test", "\\u003Cscript\\u003E"]

My problem is: I want the escaped string to be: ["test", "\u003Cscript\u003E"] instead of ["test", "\\u003Cscript\\u003E"]

I can use replace:

In [37]: print simplejson.dumps(s_esc).replace('\\\\', '\\')
["test", "\u003Cscript\u003E"]

But is this a good approach? I just want to escape the strings first before encoding them to json. So there will be no syntax errors when I use them in template.

Thanks. :)