JsonResponse
A subclass of `HttpResponse` useful as a shortcut in views; it chooses the correct JSON serializer based on whether or not it is passed a QuerySet.
- ajax
- serialize
- json
A subclass of `HttpResponse` useful as a shortcut in views; it chooses the correct JSON serializer based on whether or not it is passed a QuerySet.
Here is a Django template tag that allows you to create complex variables specified in JSON format within a template. It enables you to do stuff like: {% var as person %} { "firstName": "John", "lastName": "Smith", "address": { "streetAddress": "21 2nd Street", "city": "New York", "state": "NY", "postalCode": 10021 }, "phoneNumbers": [ "212 555-1234", "646 555-4567" ] } {% endvar %} <p>{{person.firstName}}, </br> {{person.address.postalCode}}, </br> {{person.phoneNumbers.1}} </p> This tag also enables me to do dynamic CSS using as follows: # urlpatters urlpatterns = patterns('', (r'^css/(?P<path>.*\.css)$', 'get_css'), ) #views def get_css(request, path): return render_to_response('css/%s' % path, {}, mimetype="text/css; charset=utf-8") # dynamic css within in /path/to/app/templates/css' {% load var %} {% var as col %} { "darkbg": "#999", "lightbg": "#666" } {% endvar %} {% var as dim %} { "thinmargin": "2em", "thickmargin": "10em" } {% endvar %} body { background: {{col.darkbg}}; margin: {{dim.thinmargin}}; }
This is a great way to pack extra data into a model object, where the structure is dynamic, and not relational. For instance, if you wanted to store a list of dictionaries. The data won't be classically searchable, but you can define pretty much any data construct you'd like, as long as it is JSON-serializable. It's especially useful in a JSON heavy application or one that deals with a lot of javascript. **Example** (models.py): from django.db import models from jsonfield import JSONField class Sequence(models.Model): name = models.CharField(maxlength=25) list = JSONField() **Example** (shell): fib = Sequence(name='Fibonacci') fib.list = [0, 1, 1, 2, 3, 5, 8] fib.save() fib = Sequence.objects.get(name='Fibonacci') fib.list.append(13) print fib.list [0, 1, 1, 2, 3, 5, 8, 13] fib.get_list_json() "[0, 1, 1, 2, 3, 5, 8, 13]" *Note:* You can only save JSON-serializable data. Also, dates will be converted to string-timestamps, because I don't really know what better to do with them. Finally, I'm not sure how to interact with forms yet, so that realm is a bit murky.
simple usage in tpl {% load jsonify %} <script type="text/javascript"> var object = {{ object|jsonify }}; </script>
Simple template filter to encode a variable to JSON format Usage: {% load json_filters %} {% block content %} <script type="text/javascript"><![CDATA[ var items = {{ items|jsonify }}; ]]></script> {% endblock %} I'm using JsonResponse for the views but I also want to have preloaded JSON data into the page output
I use this script to export a group of models that I want to import later as initial data. It exports them as serialized json, which is perfect for importing later with the loaddata function in manage.py.
An example of using Dojo to retrieve some information from a view (linked by the URL '/account/isavailable/') to show whether or not an account is available.
**This script converts a CSV file into a JSON file ready to be imported via `manage.py loaddata` like any other fixture data.** It can be used manually to do a one-time conversion (for placing into a /fixtures folder), or used in a fabric script that automatically converts CSV to JSON live then runs `loaddata` to import as fixture data. To run script: >`csv2json.py input_file_name model_name` > >e.g. csv2json.py airport.csv app_airport.Airport > >Note: input_file_name should be a path relative to where this script is. **Scripts depends on simplejson module.** The module can just be placed in a sub-folder to the script to make it easy to import. If you use the same Python binary that you use for your Django site, you could use the Django import instead: `from django.utils import simplejson` **File Input/Ouptut formats:** Assumes CSV files are saved with LF line endings, and that first line has field values. First column is the model's pk field. Sample CSV input: id,ident,name,city,state 1,00C,Animas Air Park,Durango,CO 6,00V,Meadow Lake,Colorado Springs,CO 7,00W,Lower Granite State,Colfax,WA 12,01J,Hilliard Airpark,Hilliard,FL Output file name is input name + ".json" extension. Sample JSON output: [ { "pk": 1, "model": "app_airport.Airport", "fields": { "name": "Animas Air Park", "city": "Durango", "ident": "00C", "state": "CO", } } ] **Debugging Conversion Problems** If JSON import errors out with "ValidationError: This value must be an integer", you probably have a blank in an Integer field within your CSV file, but if can't figure out, try setting a breakpoint in file: ./django/django/db/models/fields/__init__.py e.g. 688 try: 689 return int(value) 690 except (TypeError, ValueError): 691 import pdb; pdb.set_trace() 692 -> raise exceptions.ValidationError( 693 _("This value must be an integer.")) To figure out what field caused the error, while in the debugger: (Pdb) u <- to go UP the callstack (Pdb) field.name
Use this decorator on a function that returns a dict to get a JSON view, with error handling. Features: * response always includes a 'result' attribute ('ok' by default) * catches all errors and mails the admins * always returns JSON even on errors
These base form classes add a method to return error messages as HTML encoded as JSON from Django, optionally passing in an argument to strip tags out. The method can be called in your view after checking that your form is valid. There is a ModelForm and Form class to use depending on your needs. The sample jQuery function will take the errors returned as json, loop over the errors and insert the error after each field. If you're using a form prefix, you'll need to add a hidden field to hold the value for the prefix. The `__all__` error(s), which are not bound to a field are appended to the end of the form, which you could easily reposition. Happy coding!
Django JSON view decorator. Dumps the object returned from the view function. Allows you to customize the JSON dumps() function using the available keyword arguments available from the simplejson module. By default, indents the output with 4 characters.
This is a custom field that lets you easily store JSON data in one of your model fields. This is updated to work with Django 1.1. **Example: (models.py)** from django.db import models import JSONField class MyModel(models.Model): info = JSONField() ** Example: (shell)** >>> obj = MyModel.objects.all()[0] >>> type(obj.info) <type 'NoneType'> >>> obj.info = {"test": [1, 2, 3]} >>> obj.save() **[Code at GitHub](http://github.com/bradjasper/django-jsonfield/tree/master)**
This is a subclass of Django's built-in JSONEncoder that adds the ability to output form and field objects as ExtJS-compatible config objects. Simple example: from django.utils import simplejson json = { 'data': [], 'success': True, 'metaData': { 'fields': SFY09RDOForm(), 'root': 'data', 'successProperty': 'success' }, } return HttpResponse(simplejson.dumps(json, cls=ExtJSONEncoder)) Where SFY09RDOForm is a subclass of django.forms.Form. 6/20/2008: Updated to pass on the help_text parameter (useful in combination with this override in ext: http://extjs.com/forum/showthread.php?t=36642)
Just like it says -- set it up and run. Use it for server migrations, for project handoffs, in cron jobs, you name it. I have never had problems exporting models to individual fixtures in this way, and only one bout of trouble re-importing them (and that was, like, an impossible-triangle of OneToOneField dependencies anyway, and they were going from a sqlite file to a postgres schema that totally had inappropriate nullable columns in it). I find that the json files named for what they contain is helpful when and if manage.py does freak out during an import, as the output from `loaddata` command is so opaque it's autistic, basically. A trivial refactoring effort could make it into a management command -- it already makes use of the builtin `dumpdata` command class internally. However I did not feel like overthinking it enough to set it up in a repository (doubtlessly padded with unrelated 'utilities' and explanatory .rst files) and then writing a blog post to sell it to you. That is why you are reading this code here, instead of on GitHub. Don't get me wrong, GitHub is awesome, and like a consummate host... but not the way I love me some quick and dirty snippet code, these days. Whatever, you say lazy, I say productively relaxed, potato/potahto. Erm. In any case please do enjoy this model fixture-exporter. Yes.
Model field that stores serialized value of model class instance and returns deserialized model instance. Example usage: from django.db import models import SerializedObjectField class A(models.Model): object = SerializedObjectField(serialize_format='json') class B(models.Model): field = models.CharField(max_length=10) b = B(field='test') b.save() a = A() a.object = b a.save() a = A.object.get(pk=1) a.object <B: B object> a.object.__dict__ {'field': 'test', 'id': 1}