Dive into Code

from asgiref.sync import sync_to_async
from django.shortcuts import render


def _get_data(name):
    data = []
    for i in range(0,100000):
        data.append(f'{i} - {name}')
    return data

get_data = sync_to_async(_get_data, thread_sensitive=True)


async def home(request):
    context = {}
    data = get_data('hello word')
    context['data'] = await data
    return render(request,'home.html', context)

# it is copy paste from the django documentation 
# the difference is in this function is that  an sql string is passed as parameter instead of cursor

from django.db import connection

def dictfetchall(query):
    "Return data from raw sql query  as a dict"
    with connection.cursor() as cursor:
        cursor.execute(query)
        columns = [col[0] for col in cursor.description]
        return [
            dict(zip(columns, row))
            for row in cursor.fetchall()
        ]

class FormInvalidMixin:
    def form_invalid(self, form, **kwargs):
        from django.contrib import messages
        messages.error(self.request, f"{self.model.__name__.capitalize()} not saved.")
        for field in form.errors:
            try:
                form[field].field.widget.attrs['class'] += ' is-invalid'
            except KeyError:
                form[field].field.widget.attrs['class'] = ' is-invalid'
        return super().form_invalid(form)

import requests
from django.core.files.base import ContentFile
from django.core.management.base import BaseCommand, CommandError
from app.models import MyModel


class Command(BaseCommand):
    help = 'save images to MyModel table'


    def handle(self, *args, **options):
        for model in MyModel.objects.all():
            url = 'url_path_to_image'
            r = requests.get(url)
            if r.status_code == 200:
                data = r.content
                filename = url.split('/')[-1]
                model.image.save(filename, ContentFile(data))
                model.save()
                print(model.pk)
        self.stdout.write(self.style.SUCCESS('Successfully saved MyModel images'))

create table country(
id serial primary key not null,
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);


create table vat(
id serial primary key not null,
name varchar(200),
vat int not null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table countryvat(
country_id int references country(id),
vat_id int references vat(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(country_id, vat_id)
);

create table customer(
id serial primary key not null,
country_id int references country(id),
vat_id int references vat(id),
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table customeraddress(
id serial primary key not null,
customer_id int references customer(id),
address varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table banner(
id serial primary key not null,
location int not null default 1,
code text null,
url text null,
banner_image text null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table bannerstatistic(
id serial primary key not null,
banner_id int references banner(id),
session_id text null,
created_at timestamp not null default now()
);


create table appointment(
id serial primary key not null,
description text null,
start_at timestamp not null default now(),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table pressrelease(
id serial primary key not null,
description text null,
filepath text null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table media(
id serial primary key not null,
media_path text not null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);


create table event(
id serial primary key not null,
name varchar(200),
description text null,
start_at timestamp not null default now(),
end_at timestamp not null default now(),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table eventmedia(
event_id int references event(id),
media_id int references media(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(event_id, media_id)
);


create table supplier(
id serial primary key not null,
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table tag(
id serial primary key not null,
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);


create table brand(
id serial primary key not null,
name varchar(200),
logo_image text null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table supplierbrand(
brand_id int references brand(id),
supplier_id int references supplier(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(brand_id, supplier_id)
);


create table category(
id serial primary key not null,
hero_image text null,
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table relatedcategory(
from_category_id int references category(id),
to_category_id int references category(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(from_category_id, to_category_id)
);

create table feature(
id serial primary key not null,
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);


create table featureattribute(
id serial primary key not null,
feature_id int references feature(id),
name varchar(200),
created_at timestamp not null default now(),
updated_at timestamp not null default now()
);

create table categoryfeature(
feature_id int references feature(id),
category_id int references feature(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(feature_id, category_id)
);


create table product(
id serial primary key not null,
brand_id int null references brand(id),
name varchar(200),
hero_image text null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);


create table relatedproduct(
from_product_id int references product(id),
to_product_id int references product(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(from_product_id, to_product_id)
);


create table productsupplier(
product_id int references product(id),
supplier_id int references supplier(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(product_id, supplier_id)
);

create table productprice(
product_id int references product(id),
vat_id int references vat(id),
country_id int references country(id),
supplier_id int references supplier(id),
price NUMERIC(6, 4) not null default 0,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
is_default BOOLEAN NOT NULL default True,
PRIMARY KEY(product_id, country_id,vat_id, supplier_id)
);

create table productcustomerprice(
product_id int references product(id),
vat_id int references vat(id),
country_id int references country(id),
customer_id int references customer(id),
price NUMERIC(6, 4) not null default 0,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
is_default BOOLEAN NOT NULL default True,
PRIMARY KEY(product_id, country_id, vat_id, customer_id)
);


create table productcategory(
product_id int references product(id),
category_id int references category(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(product_id, category_id)
);

create table producttag(
product_id int references product(id),
tag_id int references tag(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(product_id, tag_id)
);

create table productmedia(
product_id int references product(id),
media_id int references media(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(product_id, media_id)
);

create table productattribute(
product_id int references product(id),
feature_id int references feature(id),
featureattribute_id int references featureattribute(id),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(product_id, feature_id, featureattribute_id)
);

create table offer(
id serial primary key not null,
name varchar(200),
description text null,
start_at timestamp not null default now(),
end_at timestamp not null default now(),
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
"order" int not null default 0,
is_published BOOLEAN NOT NULL default False,
is_active BOOLEAN NOT NULL default True
);

create table offerdetail(
product_id int references product(id),
offer_id int references offer(id),
price NUMERIC(6, 4) not null default 0,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(product_id, offer_id)
);

create table shoppingcartitem(
id serial primary key not null,
product_id int references product(id),
quantity int not null,
cart_id text not null,
created_at timestamp not null default now(),
updated_at timestamp not null default now()
);

create table "order"(
id serial primary key not null,
total NUMERIC(6, 4) not null,
quantity int not null,
email text not null,
created_at timestamp not null default now(),
updated_at timestamp not null default now()
);


create table orderdetail(
order_id int references "order"(id),
product_id int references product(id),
quantity int not null,
price NUMERIC(6, 4) not null,
created_at timestamp not null default now(),
updated_at timestamp not null default now(),
PRIMARY KEY(order_id, product_id)
);