from django.db import models
 
# Create your models here.
class Category(models.Model):
  name=models.CharField(max_length=128,unique=True)
  class Meta:
    verbose_name_plural="Categories"
  def __str__(self):
    return self.name
 
class Page(models.Model):
  category=models.ForeignKey(Category,on_delete=models.CASCADE)
  title=models.CharField(max_length=128)
  url=models.URLField()
  views=models.IntegerField(default=0)
  def __str__(self):
    return self.title

import os
# In your live server environment, you'll need to tell your WSGI application what settings
# file to use. Do that with os.environ:
#reference source:https://docs.djangoproject.com/en/3.1/topics/settings/
os.environ.setdefault('DJANGO_SETTINGS_MODULE','tango_with_django_project.settings')
 
import django
django.setup()
from rango.models import Category,Page
#If you're using components of Django “standalone” – for example, writing a Python script
# which loads some Django templates and renders them, or uses the ORM to fetch some data –
# there's one more step you'll need in addition to configuring settings.
# After you've either set DJANGO_SETTINGS_MODULE or called configure(), you'll need to call
# django.setup() to load your settings and populate Django's application registry.
# reference source:https://docs.djangoproject.com/en/3.1/topics/settings/
def populate():
  python_pages=[
    {"title":"official",
    "url":"http://docs.python.org"},
    {"title":"How to think like a computer scientis",
    "url":"http://ww.greenteapress.com/thinkpy"},
    {"title":"learn python in 10 minites",
    "url":"http://www.korokithakis.net/tutorials/python"}
  ]
 
  django_pages=[
    {"title":"Official Django tutorial",
    "url":"https://docs.jangoproject.com/en/1.9/intro"},
    {"title":"Django Rocks",
    "url":"http://www.djangorocks.com"
    },
    {"title":"HOw to tango with django",
    "url":"http://www.tangowithdjango.com"}
  ]
 
  other_pages=[
    {"title":"Bottle",
    "url":"http://bottlepy.org"},
    {"title":"Flask",
    "url":"http://flask.pocoo.org"},
    {"title":"Bold test",
    "url":"http://boldtest.org"}
  ]
  cats={"Python":{"pages":python_pages},
  "Django":{"pages":django_pages},
  "Other Frameworks":{"pages":other_pages}}
 
  def add_page(cat,title,url,views=0):
    p=Page.objects.get_or_create(category=cat,title=title,url=url,views=views)[0]
    # p.url=url
    # p.views=views
    p.save()
    return p
  def add_cat(name):
    c=Category.objects.get_or_create(name=name)[0]
    c.save()
    return c
  for cat,cat_data in cats.items():
    c=add_cat(cat)
    for p in cat_data['pages']:
      add_page(c,p["title"],p['url'])
  for c in Category.objects.all():
    for p in Page.objects.filter(category=c):
      print("-{0}-{1}".format(str(c),str(p)))
 
if __name__=="__main__":
  print("starting rango population script")
  populate()

get_or_create(defaults=None, **kwargs)
A convenience method for looking up an object with the given kwargs (may be empty if your model has defaults for all fields),<br> creating one if necessary.
Returns a tuple of (object, created), where object is the retrieved or created object and created is a boolean specifying whether a new <br>object was created.
This is meant to prevent duplicate objects from being created when requests are made in parallel, and as a shortcut to boilerplatish code. <br>