Cinema Room REST Service (Java)

A simple Spring REST service that helps managing a small movie theater.

Technical description

Features used in the project:

• Spring Boot
• Jackson

Project structure:

└── cinema
    ├── buisnesslayer
    │   ├── CinemaRoom
    │   │   ├── CinemaRoom.java                # Respresents a cinema room
    │   │   └── CinemaRoomManager.java         # Responsible for `CinemaRoom` objects
    │   ├── CinemaRoomConfig.java              # Configurations for `CinemaRoom` objects
    │   ├── CinemaRoomController.java          # Main application logic
    │   ├── exceptions                         # Custom exceptions 
    │   │   ├── CustomExceptionHandler.java
    │   │   ├── ErrorResponse.java             # Response body in case there is an error
    │   │   ├── TheSeatIsTakenException.java
    │   │   ├── WrongPasswordException.java
    │   │   ├── WrongSeatIndexException.java
    │   │   └── WrongTokenException.java
    │   └── json                               # Responsible for generating JSON objects:
    │       ├── CinemaRoomJson.java            #   Info about cinema room
    │       ├── CinemaRoomStatisticsJson.java  #   Sales statistics 
    │       ├── PurchasedTicketJson.java       #   Info about purchased ticket 
    │       ├── ReturnedTicketJson.java        #   Info about returned ticket 
    │       ├── SeatJson.java                  #   Info about a seat (row, column)
    │       └── TokenJson.java                 #   Info about customer's token
    ├── CinemaApplication.java                 # Launches application using Spring Boot
    └── databaselayer
        └── PurchasedTicketsDatabase.java      # Stores <token, tiket info> pairs 

Project Features

There are several endpoints used in the application: /seats, /purchase, /return, /stats. All of them return the response in JSON format.

/seats

Returns the information about the movie theater: the total amount of rows and columns and the list of available seats.

Example:

• GET /seats

  Response:

  {
     "total_rows":5,
     "total_columns":6,
     "available_seats":[
        {
           "row":1,
           "column":1
        },
        {
           "row":3,
           "column":2
        },
        {
           "row":5,
           "column":6
        }
     ]
  }

/purchase

Marks a booked ticket as purchased. It receives row and column in JSON format and either continues the booking process or throws TheSeatIsTakenException. If the exception is thrown, the 400 (Bad Request) status code is returned.

When a customer buys a ticket, the response body contains a randomly generated UUID token. The token and the data about the customer's ticket are stored in PurchasedTicketsDatabase.

Examples:

• POST /purchase

  {
      "row": 1,
      "column": 1
  }

  Response:

  {
      "token": "00ae15f2-1ab6-4a02-a01f-07810b42c0ee",
      "ticket": {
          "row": 1,
          "column": 1,
          "price": 10
      }
  }

• POST /purchase

  {
      "row": 1,
      "column": 1
  }

  Response:

  {
      "error": "The ticket has been already purchased!"
  }

/return

Allows customers to refund their tickets. It receives a token in JSON format and either continues the return process or throws WrongTokenException. If an exception is thrown, the 400 (Bad Request) status code is returned.

Examples:

• POST /return

  {
      "token": "00ae15f2-1ab6-4a02-a01f-07810b42c0ee"
  }

  Response:

  {
      "returned_ticket": {
          "row": 1,
          "column": 1,
          "price": 10
      }
  }

• POST /return

  {
      "token": "00ae15f2-1ab6-4a02-a01f-07810b42c0ee"
  }

  Response:

  {
      "error": "Wrong token!"
  }

/stats

Shows sales statistics: current income, amount of purchased and available seats.

Showing statistics is possible only for the theater managers. To confirm the role, the user passes the password as a URL parameter. If the password is correct, the statistics is shown, otherwise, WrongPasswordException is thrown and 401 (Unauthorized) status code is returned.

Examples:

• GET /stats

  Response:

  {
      "error": "The password is wrong!"
  }

• GET /stats?password=<user_pwd>

  Response:

  {
      "error": "The password is wrong!"
  }

• GET /stats?password=<manager_pwd>

  Response:

  {
      "current_income": 0,
      "number_of_available_seats": 81,
      "number_of_purchased_tickets": 0
  }