The prototype is deployed on: https://gentle-ridge-32032.herokuapp.com/

• Overview
• Preparation
• Deployment
  • Docker
  • Heroku
• Reset
• Django Concept
• Authentication vs Authorization
• Reference

Overview

• For the purpose of authentication, a visitor account is provided in the login page: https://gentle-ridge-32032.herokuapp.com/auth/login/
• To be able to check all of the APIs, an account to login is needed, API endpoints of the prototype: https://gentle-ridge-32032.herokuapp.com/api/

To familiarize with Django, jump to Django 101 for details.

Functions:

• User: register, login, logout
• Master/Detail: show folllowings' images
• Comments/Likes: like/unlike, comment
• Friends: follow/unfollow, following/follower
• Content: images upload

Note that instruction below is specifically for Mac, windows can be a bit different.

Preparation

Install software and tools to be used:

• Homebrew: software package management system for Mac
• Python: interpreted, high-level, general-purpose programming language
• virtualenv: manage python packages in virtual environment
• Docker: run application locally
• Heroku: deploy application in the cloud

1. Install Homebrew:

# check https://brew.sh/
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

2. Install Python via Homebrew: brew install python3
3. Install virtualenv via pip: pip install virtualenv
4. Install Docker then run.
5. Install Heroku and register
6. Create a virtual enviroment for the project via virtualenv:

# create a virtual enviroment called venv
virtualenv -p /usr/local/bin/python3 venv

# activate the virtual environment
source venv/bin/activate

7. Install all other necessary python packages via pip install -r application/requirements.txt

Run deactivate to exit the virtual environment if needed.

Deployment

Docker

Docker is quite convenient to run the application locally, follow steps below to run the application via Docker:

1. Get into current project directory
2. Prepare "Dockerfile" and "docker-compose.yml" for configuration
3. Run docker-compose up -d to setup the application through "Dockerfile" and "docker-compose.yml"
4. Open the browser and check "http://localhost:8000/", the application is already running at the backend

To stop the application, check and stop the corresponding Docker container. Step 3 to 5 are for the purpose of clean-up:

1. Check the container ID via docker ps -a
2. Stop the container docker stop {container_ID}
3. Delete the container docker rm {container_ID}
4. Check the image ID docker images
5. Delete the corresponding image docker rmi {image_ID}

Heroku

Heroku is a cloud application platform, which allows developers to deploy applications on.

Below is those python packages needed for Heroku deployment:

• gunicorn: WSGI http server for unix
• pillow: Imaging library
• whitenoise: Simplified static file serving for web applications, which makes static files uploaded possible

If not directly clone from this project, ensure to create file "Procfile" for deployment under root directory with following content:

web: gunicorn {project_path}.wsgi --log-file -

Follow steps below to deploy the application on Heroku:

1. Run source venv/bin/activate to activate the virtual environment
2. Run heroku login to use Heroku CLI
3. Ensure Django and all packages related is installed pip install -r application/requirements.txt
4. Create a new Heroku app to deploy the project:

heroku create

# add the Heroku app as a remote site if current project is git
git remote -v

5. Update "seetings.py":
   • add 'whitenoise.runserver_nostatic', in INSTALLED_APPS
   • add 'whitenoise.middleware.WhiteNoiseMiddleware', in MIDDLEWARE
   • add STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles') at the end
   • add STATICFILES_STORAGE = 'whitenoise.storage.CompressedManifestStaticFilesStorage' at the end
6. Run heroku ps:scale web=1 to use one web server only other than many.

Steps above is only needed to configure and run once, run commands below to update the project in Heroku.

source venv/bin/activate
heroku login

# add and commit all the changes
git add .
git commit -m "Deploy to Heroku"

git push heroku master

# open the web app
heroku open

NOTE THAT since "db.sqlite3" is needed for Heroku, as well as "static/images/", remember to remove or comment them in ".gitignore" to make another commit before deployment. After deployment, reset ".gitignore" to avoid accidentally uploading the DB in the public git repository with sensitive data leak.

git reset HEAD~1
git checkout .gitignore

Reset

To reset existing database and files, follow steps:

1. Remove any existing migrations:

find . -path "application/*/migrations/*.py" -not -name "__init__.py" -delete
find . -path "application/*/migrations/*.pyc"  -delete

2. Remove existing database and static files (make sure it's expected since everything would be cleanup):

rm db.sqlite3
rm -r static/images

3. Regenerate migrations and database schema:

python manage.py makemigrations
python manage.py migrate

To remove current virtual environment: rm -r venv

To remove the Heroku branch: git remote rm heroku

Reference

• Classy Class-Based Views: https://ccbv.co.uk/
• Generic display views: https://docs.djangoproject.com/en/2.2/ref/class-based-views/generic-display/
• Customizing authentication in Django: https://docs.djangoproject.com/en/2.2/topics/auth/customizing/
• Django Templates: https://docs.djangoproject.com/en/2.2/topics/templates/
• Custom template tags and filters: https://docs.djangoproject.com/en/2.2/howto/custom-template-tags/
• Access Mixins: https://django-braces.readthedocs.io/en/latest/access.html
• JiuZhang demo: https://github.com/yibeibaoke/InstaDemo
• Django Rest framework: https://www.django-rest-framework.org/
• Implement Token Authentication using Django REST Framework: https://simpleisbetterthancomplex.com/tutorial/2018/11/22/how-to-implement-token-authentication-using-django-rest-framework.html
• How to Reset Migrations: https://simpleisbetterthancomplex.com/tutorial/2016/07/26/how-to-reset-migrations.html
• SQLLite Viewer: http://sqliteviewer.flowsoft7.com/