K-in-a-Row

This is an implementation of an m, n, k-game that exposes an interface for user-created bot players.

How to play

Just set a width, height, and number to win, and hit start! If you would like to play against a bot, put their URL into the Player 1 or Player 2 fields. (More on bots below.) If you'd rather play against yourself or someone next to you, just leave those fields blank.

Creating a bot player

A bot needs to exist as a publicly available web server that responds to two routes, /status and /move. An example bot built on REPL.it using Ruby/Sinatra can be found here.

GET /status

Accessed just before the game begins, to verify that the bot is online and is able to play with the current settings. Receives the following parameters in its query string:

• width (Number): The number of columns in the board (guaranteed to be ≥ 3)
• height (Number): The number of rows in the board (guaranteed to be ≥ 3)
• k (Number): The number of cells in a row (in any direction) needed to win (guaranteed to be ≥ 3 and ≤ the larger of width and height)
• timePerMove (Number): The amount of time (in seconds) the bot will have to make each move

The server may respond with a 200 status code if it is willing to play with the provided settings, or a 418 status to indicate that it will not play.

POST /move

Accessed whenever the bot needs to make a move. Receives the following json-encoded parameters in its body:

• width (Number): The number of columns in the board (guaranteed to be ≥ 3)
• height (Number): The number of rows in the board (guaranteed to be ≥ 3)
• cells (Array): A flat array of size width×height, which are the rows of the grid concatenated together. null indicates that a cell is empty; 0 indicates that a cell is occupied by player 1, and 1 indicates that a cell is occupied by player 2.
• k (Number): The number of cells in a row (in any direction) needed to win (guaranteed to be ≥ 3 and ≤ the larger of width and height)
• timePerMove (Number): The amount of time (in seconds) the bot will have to make its move. Note that this is the time when the response must be received by the game, not when the server sends the response. (guaranteed to be ≥ 1)
• turn (Number): If 0, it is currently player 1's turn. 1 indicates that it is player 2's turn.

The server must respond with the 0-based index of the cell it wishes to move to. Note that if the bot takes too long or responds with an invalid move, it will immediately lose the game.

Example

Given the following game state:

0 _ 0 0
1 0 1 _
_ 1 _ 1

The parameters sent to /move would be:

{
  "width": 4,
  "height": 3,
  "cells": [0, null, 0, 0, 1, 0, 1, null, null, 1, null, 1],
  "k": 3,
  "timePerMove": 3,
  "turn": 0
}

An acceptable response might be

7

Running the app locally

1. Ensure that node, npm, and yarn are installed.

2. Clone the repo

git clone https://github.com/adoxography/kinarow

3. Install the dependencies

yarn install

4. Start the development server

yarn start

License

MIT