Furious Cinema

A backend service for a small cinema, which only plays movies from the Fast & Furious franchise.

Running

Before running, make sure:

• you have JDK 11 or higher installed
• you have no MongoDB instance running locally

To run the application execute:

./gradlew bootRun --args='--furious-cinema.infrastructure.http-client.omdb.api-key=<your omdb api key>'

To run tests execute:

./gradlew test

About

Here are some details about the project.

Technology stack

Tools used to implement the project:

• Spring Boot WebFlux
• Kotlin coroutines
• Resilience4j
• Embedded MongoDB
• OpenAPI 3
• Spock
• WireMock

Architecture

The project contains a single module. The codebase is organized more or less according to my article. The module implements hexagonal architecture. Application logic resides in the core package which is bounded by inbound and outbound ports. The only inbound port is FuriousCinema. All the application logic in encapsulated behind its API. Inbound adapters lie inside the rest package. REST endpoints MovieEndpoint and RepertoireEndpoint play their roles. The outbound ports are Authentications, Movies, Ratings, Repertoires. The corresponding outbound adapters, which are concrete implementations of the outbound ports, lie inside the infrastructure package. Inside the core package, source code is organized using Tactical DDD building blocks. The core package is divided into small mini-modules, one per aggregate. Every mini-module encapsulates a part of the business logic behind its facade's API.

Tests

There are only integration (E2E) tests in the project. That type of tests assures the most that the project will work as expected in the real world, although they are relatively slow. For bigger projects testing application logic in separation should be considered.

Naming

Consistent naming is one of the things that makes code more readable. The project sticks to the one name per operation and per entity throughout the whole codebase (endpoints, application logic, tests).

Open API

To view and test the REST API of the project run the project and go to Swagger UI. To get the raw JSON description of the REST API go to API documentation.

TODO

Here is the list of what should be done besides of what already exists:

• some generic logging mechanism (based on function or AspectJ) to automatically log inbound and outbound ports operations.
• ArchUnit tests

Use cases invariants

Load movies

Loads all available movies. Invariants:

• movie must have ID
• movie must have title

Load a movie

Loads a single movie. Invariants:

• movie must exist
• movie must have ID
• movie must have title
• movie must have description
• movie must have release date
• movie must have moviegoers rating
• movie must have imdb rating
• movie must have runtime

Vote for a movie

Recalculates the overall moviegoers rating of the movie because of the new user vote. Invariants:

• user must be a registered moviegoer
• movie must exist
• user mustn't vote multiple times for the same movie
• vote has rating that can be a number 1...5
• overall movie rating is an average of all user votes

Add a repertoire

Cinema owner adds an empty repertoire for a single day. Invariants:

• user must be a cinema owner
• only one repertoire per day can be added

Add a repertoire screening

Cinema owner adds a single movie screening to a daily repertoire by specifying a start time and price. Invariants:

• user must be a cinema owner
• movie must exist
• repertoire for a requested day must exist
• repertoire must have a free time slot for the whole screening runtime
• no more than one screening can be showed at the time
• whole screening must run on the same day
• price can not be 0 or lower

Load a repertoire

Loads all daily repertoire screenings. Invariants:

• repertoire must exist
• screening must have start time
• screening must have movie title
• screening must have price