Django with Redis as Cache Backend and Session Storage
Reference: https://www.djangoproject.com/ https://redis.io/
Redis is a source-available, in-memory storage, used as a distributed, in-memory key–value database, cache and message broker, with optional durability.
Storing cache and session in Redis can provide better performance.
Prerequisite:
Redis server (localhost, heroku or other redis server) running
Step 1: Preparation, Create Django Project, Inital Migration
create virtualenv: virtualenv venv
start virtualenv: venv/Scripts/activate
install Django in virtualenv: pip install django==4.2 django-redis
Create Django: django-admin startproject myproject
Go to myproject folder: cd myproject
Initial Migration: python manage.py migrate
Step 2: Create Django App
Create apps: python manage.py startapp myapp
Step 3: Project Setting: Register Apps, Set Templates Folder, Redis Config (myproject/settings.py)
...
INSTALLED_APPS = [
...
'myapp', # updated
'django_redis', # django redis
]
...
TEMPLATES = [
...
'DIRS': [Path(BASE_DIR, 'templates')], #updated
...
]
...
# redis cache and session config
CACHES = {
'default': {
'BACKEND': 'django_redis.cache.RedisCache',
'LOCATION': 'redis://localhost:6379/0', # redis location
'OPTIONS': {
'CLIENT_CLASS': 'django_redis.client.DefaultClient',
}
}
}
SESSION_ENGINE = 'django.contrib.sessions.backends.cache'
SESSION_CACHE_ALIAS = 'default' # cache alias nameStep 4: Create HTML Files in Templates Folder
Create templates folder in main app
Create templates/cache.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Title</title>
</head>
<body>
<h1>Index Homepage</h1>
<p>Request session example: {{request.session.some_example}}</p>
<a href="{% url 'add_session_data'%}">Add session data</a>
<a href="{% url 'clear_session_data'%}">Clear session data</a>
</body>
</html>Create templates/session.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Title</title>
</head>
<body>
<p>Data session example: {{my_session_data}}</p>
<a href="{% url 'add_session_data'%}">Add session data</a>
<a href="{% url 'clear_session_data'%}">Clear session data</a>
</body>
</html>Step 5: Create Function Views myapp/views.py
from django.shortcuts import render, redirect
from django.core.cache import cache
import time
# Cache Store
def cache_test(request):
template = "cache.html"
start_time = time.time()
data = None #return data
use_cache = None
my_cache_data = cache.get('my_cache_data')
if my_cache_data:
use_cache = True
data = my_cache_data
else:
data = "some example data" # lookup from database or another source which is long running process
time.sleep(5) # long running process simulation
cache.set('my_cache_data', data, timeout=3600) # Cache for 1 hour
use_cache = False
duration = time.time() - start_time
extra_context = {
"data": data,
"duration": duration,
"use_cache": use_cache,
}
return render(request, template, extra_context)
def clear_cache_data(request):
cache.clear() # clear session data
return redirect("cache_test") #after clear, will redirect to cache test without cache stored
# Session Store
def session_test(request):
template = "session.html"
my_session_data = request.session.get("my_session_data")
extra_context = {
"my_session_data": my_session_data,
}
return render(request, template, extra_context)
def add_session_data(request):
request.session["my_session_data"] = "John Doe"
return redirect("session_test")
def clear_session_data(request):
request.session.flush() # clear session data
return redirect("session_test")
Step 8: Setup URLS
Create myapp/urls.py
from django.urls import path
from . import views
urlpatterns = [
path("cache_test", views.cache_test, name="cache_test"),
path("clear_cache_data", views.clear_cache_data, name="clear_cache_data"),
path("session_test", views.session_test, name="session_test"),
path("add_session_data", views.add_session_data, name="add_session_data"),
path("clear_session_data", views.clear_session_data, name="clear_session_data"),
]Update myproject/urls.py
from django.contrib import admin
from django.urls import path, include #updated
urlpatterns = [
path('admin/', admin.site.urls),
path('', include('myapp.urls')), #updated
]Step 9: Run Server and Testing
Run Server: python manage.py runserver
Testing:
http://127.0.0.1:8000/cache_test
http://127.0.0.1:8000/session_test
Redis
