mongo_clone.py

import pymongo
from django.db.models import Model
from django.db.models.fields.files import ImageFieldFile
from django.conf import settings

def get_mongo_db():
	client = pymongo.MongoClient(settings.MONGO_DB_HOST, settings.MONGO_DB_PORT)
	db = client.test
	return db

def convert_fields(model):
	"""
	Recursive function to iterate over all fields in a Model.
	If the field is a ForeignKey, ManyToManyField or OneToOneField, 
	go into the model and recursively store fields.
	"""
	fields = model._meta.get_all_field_names()
	update_fields = {}

	for field in fields:
		try: 
			field_value = getattr(model, field)
			if getattr(field_value, 'all', None):
				"""
				Branch for a ManyToManyField.
				Iterate over each Model in and append data to a list.
				Add list to dictionary.
				"""
				fk_list = []

				for fk_model in field_value.all():
					fk_list.append(convert_fields(fk_model))

				update_fields[field] = fk_list

			elif isinstance(field_value, Model):
				"""
				Branch for a ForeignKey or OneToOneField.
				Create data for the Model and add to dictionary.
				"""

				update_fields[field] = convert_fields(field_value)

			elif isinstance(field_value, ImageFieldFile):
				"""
				Serialize an ImageField.
				"""
				try:
					update_fields[field] = field_value.path
				except ValueError:
					"""
					ValueError occurs if there is no actual File (i.e., is null).
					"""
					update_fields[field] = ""

			else:
				"""
				Branch for a standard field.
				Add data to the dictionary.
				"""

				if field == "id":
					update_fields["pg_" + model._meta.verbose_name + "_id"] = field_value
				else:
					update_fields[field] = field_value

		except AttributeError:
			"""
			ManyToManyFields will throw an AttributeError when trying to reference the parent.
			"""
			pass
			
			
	return update_fields