Django Tests with dynamic fields in hstore

.gitignore

*.pyc
.project
.pydevproject

__init__.py

add.html

<form action="/hstoredyn/add" method="post">{% csrf_token %}
{{ form.as_p }}
<input type="submit" value="Submit" />
</form>

admin.py

'''
Created on 13/10/2012

@author: iuri
'''
from hstoredyn.models import Something
from django.contrib import admin

admin.site.register(Something)

index.html

{% if somethings_list %}
    <ul>
    {% for something in somethings_list %}
        <li><a href="/hstoredyn/{{ something.id }}/">{{ something.name }}</a></li>
    {% endfor %}
    </ul>
{% else %}
    <p>No data is available.</p>
{% endif %}

manage.py

#!/usr/bin/env python
import os
import sys

if __name__ == "__main__":
    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "hstoredyn.settings")

    from django.core.management import execute_from_command_line

    execute_from_command_line(sys.argv)

models.py

'''
Created on 13/10/2012

@author: iuri
'''

from django.db import models
from django import forms

from django_orm.postgresql import hstore
from django.utils.datastructures import SortedDict
import copy
from django.forms.models import fields_for_model

class DynamicFields(models.Model):
    refer = models.CharField(max_length=120, blank=False)
    name = models.CharField(max_length=120, blank=False)
    type = models.CharField(max_length=120, blank=False)
    max_length = models.IntegerField(null=True, blank=True)

    null = models.BooleanField(default=False)
    blank = models.BooleanField(default=False)
    choices = hstore.DictionaryField(null=True)

    objects = hstore.HStoreManager()

######################################
class MyModelMeta(models.Model.__metaclass__):
    def __new__(cls, name, bases, attrs):
        super_new = super(MyModelMeta, cls).__new__

        # create it
        new_class = super_new(cls, name, bases, attrs)

        # pos create

        # override getattr/setattr/delattr
        old_getattribute = new_class.__getattribute__
        def __getattribute__(self, key):
            try:
                return old_getattribute(self, key)
            except AttributeError:
                if hasattr(self, '_dfields') and key in self._dfields:
                    return self._dfields[key]
                raise

        new_class.__getattribute__ = __getattribute__

        old_setattr = new_class.__setattr__
        def __setattr__(self, key, value):
            #print "called __setattr__(%r, %r)" % (key, value)

            if hasattr(self, '_dfields') and not key in dir(new_class):
                # XXX: search for key on table, django will call this method on many times on 
                #      __init__
                if DynamicFields.objects.filter(refer=new_class.__name__, name=key):
                    self._dfields[key] = str(value)
                    return

            old_setattr(self, key, value)

        new_class.__setattr__ = __setattr__

        old_delattr = new_class.__delattr__
        def __delattr__(self, key):
            if hasattr(self, '_dfields') and not key in dir(new_class):
                if key in self._dfields:
                    del self._dfields[key]
                    return

            return old_delattr(self, key)
        new_class.__delattr__ = __delattr__

        # override _meta.fields (property)
        _old_meta = new_class._meta
        class _meta(object):
            @property
            def dynamic_fields(self):
                fields = []
                for metafield in DynamicFields.objects.filter(refer=new_class.__name__):
                    type_ = metafield.type
                    try:
                        #FIXME: eval is the evil, use module package
                        field_klass = eval('models.%s' % type_)
                        field = field_klass(name=metafield.name,
                                            max_length=metafield.max_length,
                                            choices=metafield.choices.get('choices'),
                                            blank=metafield.blank,
                                            null=metafield.null)
                        field.attname = metafield.name
                        fields.append(field)
                    except:
                        raise \
                            TypeError(('Cannot create field for %r, maybe type %r ' + \
                                       'is not a django type') % (metafield, type_))

                return fields

            @property
            def fields(self):
                #add dynamic_fields from table
                return _old_meta.fields + self.dynamic_fields

            def __getattr__(self, key):
                return getattr(_old_meta, key)
            def __setattr__(self, key, value):
                return setattr(_old_meta, key, value)
        new_class._meta = _meta()

        # return it
        return new_class

class MyModel(models.Model):
    __metaclass__ = MyModelMeta
    objects = hstore.HStoreManager()
    _dfields = hstore.DictionaryField(db_index=True)
    class Meta:
        abstract = True

    def __init__(self, *args, **kwargs):
        super(MyModel, self).__init__(*args, **kwargs)


class MyModelFormMeta(forms.ModelForm.__metaclass__):
    def __new__(cls, name, bases, attrs):
        super_new = super(MyModelFormMeta, cls).__new__

        # create it
        new_class = super_new(cls, name, bases, attrs)

        # pos create, remove _dfields
        if '_dfields' in new_class.base_fields:
            new_class.base_fields.pop('_dfields')
        # return it
        return new_class


class MyModelForm(forms.ModelForm):
    __metaclass__ = MyModelFormMeta
    def __init__(self, *args, **kwargs):
        super(MyModelForm, self).__init__(*args, **kwargs)
        # Always override for fields (dynamic fields maybe deleted/included) 
        opts = self._meta
        if opts.model and issubclass(opts.model, MyModel):
            # If a model is defined, extract dynamic form fields from it.
            if not opts.exclude:
                opts.exclude = []
            # hide dfields
            opts.exclude.append('_dfields')
            self.fields = fields_for_model(opts.model, opts.fields,
                                              opts.exclude, opts.widgets)


#######################################################

class Something(MyModel):
    name = models.CharField(max_length=32)
    def __unicode__(self):
        return self.name

class SomethingForm(MyModelForm):
    class Meta:
        model = Something

settings.py

# Django settings for hstoredyn project.

DEBUG = True
TEMPLATE_DEBUG = DEBUG

ADMINS = (
    # ('Your Name', 'your_email@example.com'),
)

MANAGERS = ADMINS

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': 'hstore_test', # Or path to database file if using sqlite3.
        'USER': 'iuri', # Not used with sqlite3.
        'PASSWORD': '',                  # Not used with sqlite3.
        'HOST': '',                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': '',                      # Set to empty string for default. Not used with sqlite3.
    }
}

# Local time zone for this installation. Choices can be found here:
# http://en.wikipedia.org/wiki/List_of_tz_zones_by_name
# although not all choices may be available on all operating systems.
# In a Windows environment this must be set to your system time zone.
TIME_ZONE = 'America/Fortaleza'

# Language code for this installation. All choices can be found here:
# http://www.i18nguy.com/unicode/language-identifiers.html
LANGUAGE_CODE = 'pt-br'

SITE_ID = 1

# If you set this to False, Django will make some optimizations so as not
# to load the internationalization machinery.
USE_I18N = True

# If you set this to False, Django will not format dates, numbers and
# calendars according to the current locale.
USE_L10N = True

# If you set this to False, Django will not use timezone-aware datetimes.
USE_TZ = True

# Absolute filesystem path to the directory that will hold user-uploaded files.
# Example: "/home/media/media.lawrence.com/media/"
MEDIA_ROOT = ''

# URL that handles the media served from MEDIA_ROOT. Make sure to use a
# trailing slash.
# Examples: "http://media.lawrence.com/media/", "http://example.com/media/"
MEDIA_URL = ''

# Absolute path to the directory static files should be collected to.
# Don't put anything in this directory yourself; store your static files
# in apps' "static/" subdirectories and in STATICFILES_DIRS.
# Example: "/home/media/media.lawrence.com/static/"
STATIC_ROOT = ''

# URL prefix for static files.
# Example: "http://media.lawrence.com/static/"
STATIC_URL = '/static/'

# Additional locations of static files
STATICFILES_DIRS = (
    # Put strings here, like "/home/html/static" or "C:/www/django/static".
    # Always use forward slashes, even on Windows.
    # Don't forget to use absolute paths, not relative paths.
)

# List of finder classes that know how to find static files in
# various locations.
STATICFILES_FINDERS = (
    'django.contrib.staticfiles.finders.FileSystemFinder',
    'django.contrib.staticfiles.finders.AppDirectoriesFinder',
#    'django.contrib.staticfiles.finders.DefaultStorageFinder',
)

# Make this unique, and don't share it with anybody.
SECRET_KEY = '&tu0!6cg)s2xvfcxz(8csums6tjsxg#u$wpg$oy43(33^uoc%='

# List of callables that know how to import templates from various sources.
TEMPLATE_LOADERS = (
    'django.template.loaders.filesystem.Loader',
    'django.template.loaders.app_directories.Loader',
#     'django.template.loaders.eggs.Loader',
)

MIDDLEWARE_CLASSES = (
    'django.middleware.common.CommonMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    # Uncomment the next line for simple clickjacking protection:
    # 'django.middleware.clickjacking.XFrameOptionsMiddleware',
)

ROOT_URLCONF = 'hstoredyn.urls'

# Python dotted path to the WSGI application used by Django's runserver.
WSGI_APPLICATION = 'hstoredyn.wsgi.application'

TEMPLATE_DIRS = (
    # Put strings here, like "/home/html/django_templates" or "C:/www/django/templates".
    # Always use forward slashes, even on Windows.
    # Don't forget to use absolute paths, not relative paths.
    "/Users/iuri/Sources/GITHUB/hstoredyn/templates"
)

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    # Uncomment the next line to enable the admin:
    'django.contrib.admin',
    # Uncomment the next line to enable admin documentation:
    'django.contrib.admindocs',
    'hstoredyn'
)

# A sample logging configuration. The only tangible logging
# performed by this configuration is to send an email to
# the site admins on every HTTP 500 error when DEBUG=False.
# See http://docs.djangoproject.com/en/dev/topics/logging for
# more details on how to customize your logging configuration.
LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'filters': {
        'require_debug_false': {
            '()': 'django.utils.log.RequireDebugFalse'
        }
    },
    'handlers': {
        'mail_admins': {
            'level': 'ERROR',
            'filters': ['require_debug_false'],
            'class': 'django.utils.log.AdminEmailHandler'
        }
    },
    'loggers': {
        'django.request': {
            'handlers': ['mail_admins'],
            'level': 'ERROR',
            'propagate': True,
        },
    }
}

urls.py

from django.conf.urls import patterns, include, url

# Uncomment the next two lines to enable the admin:
from django.contrib import admin
admin.autodiscover()

urlpatterns = patterns('',
    # Examples:
    # url(r'^$', 'hstoredyn.views.home', name='home'),
    # url(r'^hstoredyn/', include('hstoredyn.foo.urls')),

    # Uncomment the admin/doc line below to enable admin documentation:
    url(r'^admin/doc/', include('django.contrib.admindocs.urls')),

    url(r'^hstoredyn/$', 'hstoredyn.views.index'),
    url(r'^hstoredyn/add$', 'hstoredyn.views.add'),
    url(r'^hstoredyn/(?P<some_id>\d+)/$', 'hstoredyn.views.detail'),

    # Uncomment the next line to enable the admin:
    url(r'^admin/', include(admin.site.urls)),
)

views.py

'''
Created on 13/10/2012

@author: iuri
'''

from django.template import Context, loader
from hstoredyn.models import Something
from django.http import HttpResponse
from django.http import HttpResponseRedirect
from django.shortcuts import render
from hstoredyn.models import SomethingForm

def index(request):
    somethings = Something.objects.all()
    t = loader.get_template('something/index.html')
    c = Context({
        'somethings_list': somethings,
    })
    return HttpResponse(t.render(c))

def detail(request, some_id):
    return HttpResponse("You're looking at something %s." % some_id)

def add(request):
    if request.method == 'POST': # If the form has been submitted
        form = SomethingForm(request.POST) # A form bound to the POST data
        if form.is_valid(): # All validation rules pass
            # Process the data in form.cleaned_data
            # ...
            form.save()
            return HttpResponseRedirect('/thanks/') # Redirect after POST
    else:
        form = SomethingForm() # An unbound form
        #form.as_p()

    return render(request, 'something/add.html', {
        'form': form,
    })

wsgi.py

"""
WSGI config for hstoredyn project.

This module contains the WSGI application used by Django's development server
and any production WSGI deployments. It should expose a module-level variable
named ``application``. Django's ``runserver`` and ``runfcgi`` commands discover
this application via the ``WSGI_APPLICATION`` setting.

Usually you will have the standard Django WSGI application here, but it also
might make sense to replace the whole Django WSGI application with a custom one
that later delegates to the Django one. For example, you could introduce WSGI
middleware here, or combine a Django application with an application of another
framework.

"""
import os

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "hstoredyn.settings")

# This application object is used by any WSGI server configured to use this
# file. This includes Django's development server, if the WSGI_APPLICATION
# setting points here.
from django.core.wsgi import get_wsgi_application
application = get_wsgi_application()

# Apply WSGI middleware here.
# from helloworld.wsgi import HelloWorldApplication
# application = HelloWorldApplication(application)