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Installation

  1. Install lib with pip:

    pip install jsonate

    - OR -

    Put the "jsonate" directory somewhere in your python path

  2. Add "jsonate" to your INSTALLED_APPS (in the settings.py file)

Usage

In templates

{% load jsonate_tags %}

{{ anything|jsonate }}

This is especially useful for embedding data in in data attributes for use with javascript libraries like jQuery (note jsonate-attr is identical to jsonate|escape):

<div id="user-widget" data-user="{{ user|jsonate_attr }}"></div>

<script>
    ...
    user_data = $("#user-widget").data('user');
    ...
</script>

Or just use it directly in javascript...

<script>
    var user_data = {{ user|jsonate }};
</script>

In Python

from jsonate import jsonate

# querysets
json = jsonate(User.objects.all())

# values 
json = jsonate(User.objects.values())

# model instances
json = jsonate(User.objects.get(email="my_email@gmail.com"))

Jsonate turns datetimes into iso format for easy parsing in javascript

# formatted response for ease of reading...
>>> print jsonate(User.objects.all()[0])
{
    "username": "asdfasdf", 
    "first_name": "asdf", 
    "last_name": "asdf", 
    "is_active": false, 
    "email": "asdf@example.com", 
    "is_superuser": false, 
    "is_staff": false, 
    "last_login": "2011-08-22T19:14:50.603531",  
    "id": 5, 
    "date_joined": "2011-08-22T19:14:50.220049"
}

Fields / Exclude -- Serialization options

You may specify which fields should be serialized in the meta options of your models. This affects the serialization of model instances, and querysets, just like the Admin!

Example

from django.db import models

class MyModel(models.Model):
    normal_info = models.CharField(max_length=10)
    sensitive_info = models.CharField(max_length=10)
    
    class Meta:
        jsonate_exclude = ('sensitive_info',)
        # this would also work:
        # jsonate_fields = ('normal_info',)

By default the User model in django.contrib.auth.models is monkey-patched to exclude the password field when serializing querysets or instances

If you want to specify which fields will be serialized on a per-case basis, use values() instead. like so

>>> jsonate(User.objects.values("username", "password"))
... '[{"username": "someuser", "password": "sha1$f26b2$d03a6123487fce20aabcdef0987654321abcdef0"}]'

note: this is obviously not a real password or salt :)

You can also specify a to_json() method on your model to more tightly control serialization.

When Jsonate serializes an object, the to_json() method will always be used if it is found. The method may return any object that Jsonate can serialize (be careful of infinite loops).

Example:

import time
from django.db import models

class MyModel(models.Model):
    normal_info = models.CharField(max_length=10)
    sensitive_info = models.CharField(max_length=10)

    def to_json(self):
        return {"normal_info": self.normal_info, "serialized_at": time.time()}

…

from jsonate import jsonate

my_model = MyModel(
  normal_info="hi mom", 
  sensitive_info="My Social Security number is: ###-##-####"
)

jsonate(my_model)
# {"normal_info": "hi mom", "serialized_at": 1345233658.29246}

JsonateField

JsonateField is a simple JSONField like the ever popular JSONField project. The only difference is JsonateField uses the Jsonate JSON serializer, which makes it more robust than other JSONField implementations.

example:

from django.db import models
from jsonate.fields import JsonateField

class Customer(models.Model):
    extra_data = JsonateField(blank=True, null=True)

    …

customer = Customer()
customer.extra_data = {
    "height": 65,
    "weight": 115,
}
customer.save()

Don't ask me why you'd care about your customer's height and weight.

In Forms

If you want the Json input to be validated there is a validator:

from django import forms
from jsonate.form_fields import JsonateValidator

class MyForm(forms.Form):
    json_input = forms.CharField(validators=[JsonateValidator])

...but you should probably just use the JsonateFormField (which uses the validator):

from django import forms
from jsonate.form_fields import JsonateFormField

class MyForm(forms.Form):
    json_input = JsonateFormField()

In the Admin

If you're using the JsonateField in any of your models you'll probably want the input to be validated in the admin (using the JsonateFormField):

from django.contrib import admin
from myapp.models import MyModel

# Add this to your imports:
from jsonate.fields import JsonateField
from jsonate.form_fields import JsonateFormField


class MyModelAdmin(admin.ModelAdmin):

    # Add this to your ModelAdmin:
    formfield_overrides = {
        JsonateField: {'form_class': JsonateFormField }
    }

The JsonateResponse

JsonateResponse is a subclass of HttpResponse that works almost exactly the same, except that it accepts any object as it's data rather than just strings. It returns the resulting json as mimetype "application/json"

example:

from jsonate.http import JsonateResponse

def my_view(request):
    ...
    return JsonateResponse(request.user)
    
# response contains:
{"username": "asdfasdf", "first_name": "asdf", "last_name": "asdf", "is_active": false, "email": "asdf@example.com", "is_superuser": false, "is_staff": false, "last_login": "2011-08-22T19:14:50.603531", "id": 5, "date_joined": "2011-08-22T19:14:50.220049"}

Decorator

The JsonateResponse is great, but life could get even easier! The @jsonate_request decorator (inspired by the ajax_request decorator in django-annoying) will try to serialize anything a view returns (via JsonateResponse) return it in an HttpResponse with mimetype "application/json"

The only thing it will not try to serialize is an HttpResponse.

example:

@jsonate_request
def my_view(request):
    form = MyForm(request.POST)
    if form.is_valid():
        form.save()
        return HttpResponseRedirect("/some/path/")
    else:
        return form.errors

With valid input, the HttpResponseRedirect passes through, untouched.

If there are form errors the response comes back looking something like this:

{
  "username": [
    "This username is already taken"
  ], 
  "email": [
    "Please enter a valid email."
  ]
}