Django

Install

$ pip install django

Django Admin usage

Create project

$ django-admin startproject NEW_PROJECT

Create app in project

Recommended to first navigate:

$ cd NEW_PROJECT

$ django-admin startapp NEW_APP

$ python manage.py startapp NEW_APP

Shell

$ django-admin shell

Tests

$ django-admin test

Manage usage

Port 8000:

$ python manage.py runserver

Override:

$ python manage.py runserver 9000

Make migrations based on model changes:

$ python manage.py makemigrations

Migrate:

$ python manage.py migrate

Collect static files:

$ python manage.py collectstatic

Users

Create admin user.

$ python manage.py createsuperuser

Change user’s password.

$ python manage.py changepassword USERNAME

Filter syntax

These are just some examples of the many filter lookups available in Django. For more information, you can refer to the Django documentation on QuerySet API reference.

exact: Performs an exact match lookup. For example:
```
 Model.objects.filter(name__exact='John')
```
iexact: Performs a case-insensitive exact match lookup. For example:
```
 Model.objects.filter(name__iexact='john')
```
contains: Performs a case-sensitive substring match lookup. For example:
```
 Model.objects.filter(name__contains='oh')
```
icontains: Performs a case-insensitive substring match lookup. For example:
```
 Model.objects.filter(name__icontains='OH')
```
in: Matches any of the given values. For example:
```
 Model.objects.filter(id__in=[1, 2, 3])
```
gt: Matches values greater than the given value. For example:
```
 Model.objects.filter(age__gt=18)
```
lt: Matches values less than the given value. For example:
```
 Model.objects.filter(age__lt=30)
```
gte: Matches values greater than or equal to the given value. For example:
```
 Model.objects.filter(age__gte=18)
```
lte: Matches values less than or equal to the given value. For example:
```
 Model.objects.filter(age__lte=30)
```
startswith: Matches values that start with the given substring. For example:
```
Model.objects.filter(name__startswith='Joh')
```
endswith: Matches values that end with the given substring. For example:
```
Model.objects.filter(name__endswith='n')
```
range: Matches values within a range. For example:
```
Model.objects.filter(age__range=(18, 30))
```
year: Matches the year of a DateTimeField. For example:
```
Model.objects.filter(pub_date__year=2022)
```
month: Matches the month of a DateTimeField. For example:
```
Model.objects.filter(pub_date__month=6)
```
day: Matches the day of a DateTimeField. For example:
```
Model.objects.filter(pub_date__day=24)
```

week_day: Matches the day of the week of a DateTimeField, where Sunday=1 and Saturday=7. For example:

Model.objects.filter(pub_date__week_day=2)  # Matches all records with a pub_date on a Tuesday

isnull: Matches records where a field is null or not null. For example:

Model.objects.filter(some_field__isnull=True)  # Matches all records where some_field is null

regex: Matches records where a field matches a regular expression. For example:

Model.objects.filter(name__regex=r'^[A-Za-z]+$')  # Matches all records where name contains only letters

Django MVT

Django follows MVT (Model, View, Template) architecture.

Model

The model represents the schema of the database.

from django.db import models 


class Product(models.Model):
    product_id = models.AutoField

View

View decide what data gets delivered to the template.

from django.http import HttpResponse

def index(request):
    return HttpResponse("My content")

Using a class:

from django.views import View
  

class MyClass(View):
    def get(self, request):

Template

A sample .html file that contains HTML, CSS and Javascript.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
  
    <title>My title</title>
</head>
<body>
    <h1>My heading</h1>
</body>
</html>

URLs

from django.contrib import admin
from django.urls import path


from . import views


urlpatterns = [
    path('admin/', admin.site.urls),
    path('', views.index, name='index'),
    path('about/', views.about, name='about'),
]

Settings

INSTALLED_APPS = [ 
    'django.contrib.admin', 
    'django.contrib.auth', 
    'django.contrib.contenttypes', 
    'django.contrib.sessions', 
    'django.contrib.messages', 
    'django.contrib.staticfiles', 
    'AppName' 
]

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': ["templates"],
        'APP_DIRS': True,
        'OPTIONS': {
            # ..
        },
    },
]