= Django REST framework =
 * https://www.django-rest-framework.org/tutorial/quickstart/#quickstart
Django REST framework is a powerful and flexible toolkit for building Web APIs.

== Quickstart ==
 * Based on https://www.django-rest-framework.org/tutorial/quickstart/#quickstart
{{{#!highlight bash
cd ~/tmp
mkdir django-rest-test
cd django-rest-test
sudo apt install python3-venv
python3 -m venv virtenv
. virtenv/bin/activate
pip install djangorestframework
find . virtenv/
django-admin startproject tutorial . 
cd tutorial
django-admin startapp quickstart
cd ..
python manage.py migrate # sync DB 
python manage.py createsuperuser --email admin@example.com --username admin # create super user, pwd: 12345678 
nano tutorial/quickstart/serializers.py
nano tutorial/quickstart/views.py
nano tutorial/urls.py
nano tutorial/settings.py
python manage.py runserver
# Starting development server at http://127.0.0.1:8000/
curl -H 'Accept: application/json; indent=4' -u admin:12345678 http://127.0.0.1:8000/users/

sqlite3 db.sqlite3
.tables 
select * from auth_user;
.exit 

}}}

=== tutorial/quickstart/serializers.py ===
{{{#!highlight python
from django.contrib.auth.models import User, Group
from rest_framework import serializers

class UserSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = User
        # select fields to return
        fields = ['url', 'username', 'email', 'groups']

class GroupSerializer(serializers.HyperlinkedModelSerializer):
    class Meta:
        model = Group
        # select fields to return
        fields = ['url', 'name']
}}}

=== tutorial/quickstart/views.py ===
{{{#!highlight python
from django.contrib.auth.models import User, Group
from rest_framework import viewsets
from rest_framework import permissions
from tutorial.quickstart.serializers import UserSerializer, GroupSerializer
from django.views.decorators.csrf import csrf_exempt
from rest_framework.authentication import SessionAuthentication, BasicAuthentication
from rest_framework.permissions import IsAuthenticated
from rest_framework.response import Response
from rest_framework.decorators import api_view, authentication_classes, permission_classes
from rest_framework.views import APIView


class UserViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows users to be viewed or edited.
    """
    queryset = User.objects.all().order_by('-date_joined')
    serializer_class = UserSerializer
    permission_classes = [permissions.IsAuthenticated]


class GroupViewSet(viewsets.ModelViewSet):
    """
    API endpoint that allows groups to be viewed or edited.
    """
    queryset = Group.objects.all()
    serializer_class = GroupSerializer
    permission_classes = [permissions.IsAuthenticated]


@csrf_exempt
@api_view(['GET'])
@authentication_classes([SessionAuthentication, BasicAuthentication])
@permission_classes([IsAuthenticated])
def hello_world(request):
    """
    Function view
    """
    return Response({"message": "Hello world", "user": str(request.user)})


class HelloWorldAnonView(APIView):
    def get(self, request, format=None):
        return Response({"message": "Hello world anonymous", "user": str(request.user)})


class HelloWorldViewSet(viewsets.ViewSet):
    # authentication required
    permission_classes = [permissions.IsAuthenticated]

    def list(self, request):
        return Response({"message": "Hello world view set up and running " + str(request.user)})}}}

=== tutorial/urls.py ===
{{{#!highlight python
from django.urls import include, path
from rest_framework import routers
from tutorial.quickstart import views

router = routers.DefaultRouter()
router.register(r'users', views.UserViewSet)
router.register(r'groups', views.GroupViewSet)
router.register(r'helloworldviewset', views.HelloWorldViewSet,basename="")

# Wire up our API using automatic URL routing.
# Additionally, we include login URLs for the browsable API.
urlpatterns = [
    path('', include(router.urls)),
    path('api-auth/', include('rest_framework.urls', namespace='rest_framework')),
    path('helloworld/',views.hello_world),
    path('helloworldanon/',views.HelloWorldAnonView.as_view()),
]
}}}

=== tutorial/settings.py ===
{{{#!highlight python
"""
Django settings for tutorial project.

Generated by 'django-admin startproject' using Django 3.2.5.

For more information on this file, see
https://docs.djangoproject.com/en/3.2/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/3.2/ref/settings/
"""

from pathlib import Path
import os
# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/3.2/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = 'django-insecure-j8vs^2rq97)%g%v4fk-nl(3pho4ve)=6%&$**0++$p%v514r8r'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

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

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
]

ROOT_URLCONF = 'tutorial.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [],
        'APP_DIRS': True,
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
                'django.contrib.messages.context_processors.messages',
            ],
        },
    },
]

WSGI_APPLICATION = 'tutorial.wsgi.application'


# Database
# https://docs.djangoproject.com/en/3.2/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': BASE_DIR / 'db.sqlite3',
    }
}


# Password validation
# https://docs.djangoproject.com/en/3.2/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]


# Internationalization
# https://docs.djangoproject.com/en/3.2/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/3.2/howto/static-files/

STATIC_URL = '/static/'
STATIC_ROOT = os.path.join(BASE_DIR, 'static')
STATICFILES_DIRS = (
    ("others", os.path.join(STATIC_ROOT,'others')),
)

# Default primary key field type
# https://docs.djangoproject.com/en/3.2/ref/settings/#default-auto-field

DEFAULT_AUTO_FIELD = 'django.db.models.BigAutoField'

REST_FRAMEWORK = {
    'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
    'PAGE_SIZE': 10
}
}}}