README

This Neo4j-based example app displays movie and person data in a manner similar to IMDB. It is designed to serve as a template for further development projects. There are two versions of the backend - a Python/Flask backend at /flask-api, and a JavaScript/Express backend at /api. The web frontend can be found at /web. Feel encouraged to fork and update this repo!

The Model

Nodes

• Movie
• Person
• Genre

Relationships

• (:Person)-[:ACTED_IN {role:"some role"}]->(:Movie)
• (:Person)-[:DIRECTED]->(:Movie)
• (:Person)-[:WRITER_OF]->(:Movie)
• (:Person)-[:PRODUCED]->(:Movie)
• (:MOVIE)-[:HAS_GENRE]->(:Genre)

Database Setup: Sandbox

Go to https://sandbox.neo4j.com/?usecase=recommendations&ref=movie-app-tutorial, pick "Recommendations", and press play to start the database.

Make sure to edit the file flask-api/.env or api/.env and update the MOVIE_DATABASE_USERNAME, MOVIE_DATABASE_PASSWORD, and MOVIE_DATABASE_URL of your chosen backend to connect to your instance.

Node API

First, configure your api/.env file to point to your database.

Then, from the root directory of this project:

• cd api
• nvm use
• npm install
• node app.js starts the API
• Take a look at the docs at http://localhost:3000/docs

Alternative: Flask API

First, configure your flask-api/.env file to point to your database.

Then, from the root directory of this project:

cd flask-api
python3 -m venv venv
source venv/bin/activate
pip3 install -r requirements.txt
export FLASK_APP=app.py
flask run

• Take a look at the docs at http://localhost:5000/docs

Frontend

From the root directory of this project, set up and start the frontend with:

• cd web
• nvm use
• npm install
• update web/.env file

If you are using the Node API set REACT_APP_API_BASE_URL to http://localhost:3000/api/v0

If you are using the Flask api then set it to http://localhost:5000/api/v0

• npm start starts the app on http://localhost:3000/

voilà! IMDB, eat your heart out ;-)

Ratings and Recommendations

User-Centric, User-Based Recommendations

Based on my similarity to other users, user Omar Huffman might be interested in movies rated highly by users with similar ratings as himself.

MATCH (me:User {name:"Omar Huffman"})-[my:RATED]->(m:Movie)
MATCH (other:User)-[their:RATED]->(m)
WHERE me <> other
AND abs(my.rating - their.rating) < 2
WITH other,m
MATCH (other)-[otherRating:RATED]->(movie:Movie)
WHERE movie <> m
WITH avg(otherRating.rating) AS avgRating, movie
RETURN movie
ORDER BY avgRating desc
LIMIT 25

Contributing

Node.js/Express API

The Express API is located in the /api folder.

Create Endpoint

The API itself is created using the Express web framework for Node.js. The API endpoints are documented using Swagger.

To add a new API endpoint there are 3 steps:

1. Create a new route method in /api/routes directory
2. Describe the method with swagger specification inside a JSDoc comment to make it visible in swagger
3. Add the new route method to the list of route methods in /api/app.js.

Flask API

The Flask API is located in the /flask-api folder. The application code is in the app.py file.

Create Endpoint

The API itself is created using the Flask-RESTful library. The API endpoints are documented using Swagger.

To add a new API endpoint there are 3 steps:

1. Create a new Flask-RESTful resource class
2. Create an endpoint method including the swagger docs decorator.
3. Add the new resource to the API at the bottom of the file.