Popflix

This is a Django REST based media manager designed with an adaptive & hierarchical file structure. Popflix would function as an ideal API back-end for any media manager project whether the key file type was audio, video, text etc, etc. There is a full choice of bonus features including a testing suite, advanced filtering, containerization and CI/CD prebuilt.

• Table of Contents:
  • Features
  • Technologies
  • Deployment
  • Database Design

Features:

API

• Adaptive API allowing completely arbitrary depth of Channels/objects, see location:

  popflix\contents\api
  

Channel rating command

• Depth-first search algorithm to trace all nodes (Channel's ratings), summing them on each branch (superchannel) backtracking to root (origin Channel).

• To run this management command, add below to terminal:

  python manage.py channel_ratings
  

• Warning : This command may differ depending on operating system, the command required could be python3 or py

Filtering

• Category (Groups) options available to each superchannel that can be easily query filtered.

• Add query statement below as suffix to active superchannel url:

  ?group=name_of_group
  

Testing suite

• Unit testing accommodates all project features with test coverage of over 93%.

• To run coverage tests, use this command in terminal:

  coverage run --source='.' manage.py test
  

• Coverage report available with command:

  coverage report
  

Explanations:

These notes develop on the more interesting parts of the project

API

• To facilitate an arbitrary depth of Channels in the API, the final item in the URL is taken as the key object and searched. The URL path is found retroactively by tracing parent Channels. Filtering for Groups is achieved by checking for a group channel parameter.

API ListView

• A generic view for listing Channels with several overrides.

  • Overridden dispatch method for handling URL validation and routing. Also handles the extraction of a group parameter from the GET request.

  • The get_queryset method is overridden to provide a queryset that filters Channels based on a channel or an optional group parameter.

API URL pattern:

• URL pattern for the ListView with a dynamic path and optional group parameter.

  • This pattern captures a path and passes it to the ListView. The path here is the hierarchy of Channels. The path is required, while the group is optional and can be omitted from the URL.

API URL validator

• A utility class for validating URLs against Channel and Content slugs.

  • This class provides static methods to check the existence of Channels and Contents based on the slug and ensures that the URL matches the hierarchy of superchannels.

Channel rating command

• A management command that calculates the average rating for each active Channel and its subchannels. It uses depth-first traversal to aggregate subchannel ratings and then calculates averages

  Noteworthy methods:

  • handle executes the command, calling "get_channel_ratings()" and writing the results to a csv file.
  • get_channel_ratings processes each Channel, sums subchannel ratings, calls "get_all_subchannels()".
  • get_all_subchannels performs an iterative depth-first traversal of a Channel hierarchy, collecting and returning all visited Channels and their aggregate ratings.

Channel model

• Represents a Channel instance, object hierarchy and Group-Channel relationship set here.

  Noteworthy fields:

  • groups allows channels to be part of multiple Groups as it's set as a many-to-many relationship.
  • superchannel creates a hierarchical relationship between Channels as foreign key to another Channel/'self'

  Noteworthy methods:

  • save sets the slug and potentially updates related superchannels' Groups.
  • get_all_superchannels gets a list of all superchannels for a Channel.
  • add_group_to_superchannels adds the Channel's Groups to all of its superchannels.

ChannelManager

• Custom model manager to retrieve and filter Channels.

  • get_channels_by_group filters a given queryset of Channels by a group name.

Technologies:

• Python
  • Python 3.11.0 - Used as base language.
• Django
  • Django 4.2.8 - A Python web framework for rapid development.
  • Django REST 3.14.0 - Django-based toolkit for building Web APIs.
• Database
  • SQlite 3.38.4 - For a development database, provided by Django.
• Testing
  • Coverage 7.4.0 - Code coverage measurement for Python.
• Docker
  • Docker - Platform designed to help build, share, and run container applications.
• CI/CD
  • GitHub Actions - Build, test, and deploy from your remote storage.

Deployment:

Local Deployment:

Please note - in order to run this project locally on your own system, you will need the following installed:

• Python3 to run the application.
• PIP to install app requirements.
• GIT for version control.

1. Clone the Popflix repository by either downloading from here or type the following command into your terminal:

   git clone https://github.com/isntlee/PopFlix
   

2. Stay in your current folder, don't navigate into Popflix yet

3. A virtual environment is recommended for the Python interpreter. Enter the command:

   python -m venv venv
   

• Warning : This Python command may differ depending on operating system, the command required could be python3 or py

4. Navigate into Popflix and initialize the virtual environment by using the following command:

   ..\venv\Scripts\Activate.ps1 
   

• Warning : This command may differ depending on your operating system

5. Install all the requirements and dependancies with the command:

   pip install -r requirements.txt
   

6. Migrate the admin models to create your database template with the terminal command:

   python manage.py migrate
   

7. Create your superuser to access the django admin panel and database with the following command:

   python manage.py createsuperuser
   

8. Enter these details for the initial superuser. Ignore all warnings, don't add an email. Change the User password afterwards as this password is exposed. However, if you plan to add the prebuilt data below, you'll need these details to login, change User password after that.

   Username = iam_the_law -- Password = 2000
   

9. You can now run the program locally with the following command:

   python manage.py runserver
   

10. Once the program is running, go to localhost and add /admin/ to the end of the url. Here log in with the initial superuser account.

11. Create env.py file at root level where you can store your sensitive information for the app. Add these details to that file:

    SECRET_KEY = "SECRET_KEY"
    DEBUG = "DEBUG"
    

12. Create a new and truly secret key, which will be generated in a secret_key.txt file at root level, with this command:

    python core/generate_key.py
    

13. Find the SECRET_KEY and DEBUG variables in the core/settings.py file. You'll find two sets of SECRET_KEY and DEBUG variables: commented out and uncommented. You should comment out the uncommented, and vice-versa.

14. Finally, set the variables in your .env file. Set SECRET_KEY to the text found in secret_key.txt, remember to add '' as it should be a string. Set DEBUG to whatever you prefer, there are no security problems with DEBUG = 'True' in development. Do change for production.

15. If you would like to start with Channel/Content/User test data, then run this command:

    python manage.py loaddata data/popflix_data.json
    

Dockerize Application:

Please note - in order to run this container on your system, you will need Docker installed on your system. And, some working knowledge.

• Docker - to build and run this containerized application, add these commands to your terminal:

1. To build (if unbuilt) and start the container in detatched mode:

   docker-compose up -d
   

2. To stop and remove the container:

   docker-compose down
   

3. To use the relevant local deployment instructions above, prefix the commands with:

   docker-compose exec web
   

Database Design:

• SQlite - For development database, provided by Django.

Data Models:

Users

The User model utilized for this project is the standard one provided by django.contrib.auth.models

Group model

Name	Key in DB	Validation	Field Type
Title	title	max_length=250	CharField
Active	active	default=True, null=True	BooleanField
Picture Url	picture_url	max_length=250, null=True, blank=True	URLField
Slug	slug	max_length=250, unique=True, null=True, blank=True	SlugField

Channel model

Name	Key in DB	Validation	Field Type
Title	title	max_length=250	CharField
Language	language	max_length=250	CharField
Active	active	default=True, null=True	BooleanField
Picture Url	picture_url	max_length=250, null=True, blank=True	URLField
Groups	groups	blank=True	ManyToManyField
Slug	slug	max_length=250, unique=True, null=True, blank=True	SlugField
Superchannel	superchannel	on_delete=models.SET_NULL, null=True, blank=True	ForeignKey

Content model

Name	Key in DB	Validation	Field Type
Name	name	max_length=250	CharField
Metadata	metadata	null=True, blank=True	JSONField
File Url	file_url	max_length=250	URLField
Active	active	default=True, null=True	BooleanField
Slug	slug	max_length=250, unique=True, null=True, blank=True	SlugField
Rating	rating	MinValueValidator(0), MaxValueValidator(10)	DecimalField
Channel	channel	on_delete=models.SET_NULL, null=True, blank=True	ForeignKey