noxes - Noughts and Crosses

RESTful Web API for managing multiple concurrent TicTacToe games.

Architecture

The project is split into 3 parts:

1. TicTacToe library: Defines the logic for a single game.
2. Game Manager: Manages multiple games at a time.
3. Web API: Defines the API and launches the web server, handling all HTTP requests and responses.

Missing features / future improvements

• API testing.
• Authentication: Anyone can make a request to play as either nought or cross on any game. Play nice (for now)!
• Persistent storage: There is no database to store the game data if the server goes down. All is within memory, and resets when server does. Careful!
• GUI: No flashy frontend yet. Please play using your favourite API tool.

Running locally

1. Install Go.
2. Clone and run:

git clone https://github.com/Frezzle/noxes
go run noxes/server.go

3. Play using the API. The web server listens on http://localhost:9876 by default.

Unit tests can be run with go test noxes/...

API

Errors

All endpoints, upon some failure, return an error response:

{
    "error": "some error message"
}

POST /game/create

Creates a new game instance.

Response:

{
    "id": "0"
}

• id - Uniquely identifies the new game instance.

GET /game

Gets the state of an existing game, given a game id. Unfortunately, the /game endpoint currently requires a GET method with a body, so you must use tools which allow providing a body in a GET request (i.e. not Swagger Inspector).

Request:

{
    "id": "0"
}

• id - Uniquely identifies an existing game instance.

Response:

{
    "id": "0",
    "board": "---------",
    "nextTurn": "X",
    "gameOver": "false",
    "winner": "-"
}

• id - Uniquely identifies the game instance.
• board - 9-character string representing the cells of the board, with X, O, and - being Cross, Nought and empty respectively. Each string index is mapped to a position on the board:

    0 | 1 | 2
   -----------
    3 | 4 | 5
   -----------
    6 | 7 | 8
  

• nextTurn - who is next to play; X or O. X always starts.
• gameOver - true or false, signifying if a game is over. The game ends when a player achieves 3-in-a-row or a draw occurs.
• winner - who won the game. Starts with noone as the winner (-), becoming X or O if someone wins; stays as - if game ends as a draw.

GET /games

Gets the state of all existing games.

Response is an array of zero or more games:

[
    {
        "id": "0",
        "board": "---------",
        "nextTurn": "X",
        "gameOver": "false",
        "winner": "-"
    },
    {
        "id": "1",
        "board": "---X-----",
        "nextTurn": "O",
        "gameOver": "false",
        "winner": "-"
    }
]

See GET /game for the meaning of each game's attributes shown above.

POST /game/move

Play a move on an existing game.

Request:

{
    "gameId": "0",
    "player": "X",
    "location": "4"
}

• gameId - Identifies the game instance where you'd like to play the move.
• player - The side you are playing as; either X or O.
• location - The cell which you'd like to place your move. The board cells are mapped from 0 to 8:

    0 | 1 | 2
   -----------
    3 | 4 | 5
   -----------
    6 | 7 | 8
  

If your move was successful then the response is a 200 OK status with no body.

Bonus

How many valid board permutations are there for a TicTacToe game?

go run noxes/permutations/permutations.go