django, "is not JSON serializable" when using ugettext_lazy?

Question

I have this in my views.py

response_dict = {     'status': status,     'message': message } return HttpResponse(simplejson.dumps(response_dict),                     mimetype='application/javascript') 

Since I start using this import:

from django.utils.translation import ugettext_lazy as _

at this line:

message = _('This is a test message')

I get this error:

 File "/home/chris/work/project/prokject/main/views.py", line 830, in fooFunc     return HttpResponse(simplejson.dumps(response_dict),    File "/usr/local/lib/python2.7/json/__init__.py", line 243, in dumps     return _default_encoder.encode(obj)    File "/usr/local/lib/python2.7/json/encoder.py", line 207, in encode     chunks = self.iterencode(o, _one_shot=True)    File "/usr/local/lib/python2.7/json/encoder.py", line 270, in iterencode     return _iterencode(o, 0)    File "/usr/local/lib/python2.7/json/encoder.py", line 184, in default     raise TypeError(repr(o) + " is not JSON serializable")  TypeError: <django.utils.functional.__proxy__ object at 0x7f42d581b590> is not JSON serializable 

Why? What am I doing wrong?

Answer 1

You can also create you own JSON encoder that will force __proxy__ to unicode.

From https://docs.djangoproject.com/en/1.8/topics/serialization/

from django.utils.functional import Promise from django.utils.encoding import force_text from django.core.serializers.json import DjangoJSONEncoder  class LazyEncoder(DjangoJSONEncoder):     def default(self, obj):         if isinstance(obj, Promise):             return force_text(obj)         return super(LazyEncoder, self).default(obj) 

So now your code can look like:

response_dict = {     'status': status,     'message': _('Your message') }  return HttpResponse(json.dumps(response_dict, cls=LazyEncoder),                     mimetype='application/javascript')