Game Of Life Coding Test

Assignment

This test is designed to assess a candidate's general level of PHP/JS coding ability without reference to any particular framework. It is intended to be a test of style as well as ability. You will implement a cellular automaton as per the rules of Conway's Game of Life, that can be found at http://en.wikipedia.org/wiki/Conway%27s_Game_of_Life.

The program will be able to be deployed onto a web server as a set of PHP/JS scripts that will output animated preview to the calling browser. The program will be delivered as a .tar.gz archive. You may include a 3rd party framework if you wish (this might help with providing unit tests)

A user will visit an index.php that will give them the choice of having either a random initial condition of the game grid, or a Gosper Glider Gun (info on this can be found at the above URL). The user will be delivered a web page that includes an animated grid preview that shows at least the first 100 iterations of life based on a 38 x 38 starting grid. If you want you might extend functionalities further in example adding ability to save in database or local storage information about designed pattern/grid etc.

You will use Object-Oriented programming style. Try not to implement procedural code dressed up as objects (although given the nature of this task there will be limits)

Provide unit tests for extra marks.

You will be judged on your coding style, on the efficiency of your implementation and whether you provide unit tests.

Business Requirements

• The game of life functionality will be implemented purely in Javascript
• The overall functionality of the website will be implemented in PHP.
• The application will be implemented using Silex as a PHP framework, vanilla Javascript and Docker.

User journey

Front page

• In the frot page the user will see two buttons, "Random pattern", and "Gosper Glider Gun".
• Each of the button will redirect the user to a different page.

Random pattern page

• This page will show a functional grid of 38x38 started with a random pattern.
• The user will have three controls to stop, resume or restart the Game of Life
• The user will se the generation number and the populaiton count in real time

Gosper Glider Gun page

• This page will show a functional grid of 38x38 started with a Gosper Glider Gun.
• The user will have three controls to stop, resume or restart the Game of Life
• The user will se the generation number and the populaiton count in real time

Tests page

• In this page the tests will run using QUnit

Requirements

• Docker
• MySQL server (>=5.6) with a database named "ecp"

Installation

TL;DR: run ./deploy/up.sh.

This application is dockerized, which means that everything happens inside a Docker container. The Apache server is running inside the container (as the default entrypoint), the dependencies (Composer and NPM) are installed inside the container and PHP is executed inside the container. To spin up the Docker container (build the image and run the container), just run ./deploy/up.sh.

Development

TL;DR: run ./deploy/local.up.sh once and start coding.

When developing in a local environment, just run ./deploy/local.up.sh. This will build the image and run the container normally, but mounting volumes for the source and vendors folders.

By mounting volumes on those folders, it makes the dependencies (installed only inside the container) available outside the container (so available to your IDE). Also it makes all changes on those folders reflect instantly inside the container, so there is no need to re-deploy.

Running ./deploy/local.up.sh will also automatically tail the output of the container.

Environment variables available

These environment variables are used and given a default value only in the up.sh and local.up.sh scripts as part of the docker build and run commands. If you build the docker image and run the docker container on your own, make sure to pass the values to those commands accordingly.

ENV VAR	Default value	Description
PROJECT_NAME	Name of the project's root folder	Used to name the docker image and docker container from the up.sh files
HOST_PORT	80	The port Docker will use as the host port in the network bridge. This is the external port, the one your app will be called through
OPTIMIZE_PHP	true for up.sh, false for local.up.sh	Set PHP's configuration values about error reporting and display the right way and enables OPCache (build argument only)
OPTIMIZE_COMPOSER	true for up.sh, false for local.up.sh	Optimize Composer's autoload with Optimization Level 2/A (build argument only)
OPTIMIZE_ASSETS	true for up.sh, false for local.up.sh	Optimize assets compilation (build argument only)
BASIC_AUTH_ENABLED	true for up.sh, false for local.up.sh	Enable Basic Authentication with Apache (Persisted environment variable)
BASIC_AUTH_USER	admin	If BASIC_AUTH_ENABLED is true, this will be used to run htpasswd together with BASIC_AUTH_PASSWORD to encrypt with bcrypt (cost 10) (build argument only)
BASIC_AUTH_PASSWORD	PROJECT_NAME_password	If BASIC_AUTH_ENABLED is true, this will be used to run htpasswd together with BASIC_AUTH_USER to encrypt with bcrypt (cost 10) (build argument only)
XDEBUG_ENABLED	false for up.sh, true for local.up.sh	Enables Xdebug inside the container. More information on how to configure your system below. (build argument only)
XDEBUG_REMOTE_HOST	10.254.254.254	Used as the xdebug.remote_host PHP ini configuration value (build argument only)
XDEBUG_REMOTE_PORT	9000	Used as the xdebug.remote_port PHP ini configuration value (build argument only)
XDEBUG_IDE_KEY	PROJECT_NAME_PHPSTORM	Used as the xdebug.idekey PHP ini configuration value (build argument only)

Running commands

Since the application runs inside the container, all commands have to be executed there. To do so, run docker exec -it ecp /bin/sh -c "{command}". For example, to run a Artisan command, run docker exec -it ecp /bin/sh -c "php artisan"

Admin user

The first time you will need to create and admin user. Run the createAdminUser artisan-enabled command (i.e.: docker exec -it ecp /bin/sh -c "php artisan createAdminUser". It will ask for name, email and password and then it will create the admin user in the database. After logging in as the admin user you can then go to the users management section and create other users.

Watch assets

To watch the assets (see the compiled changes instantly reflect after every change) run docker exec -it -w /var/www ecp /bin/sh -c "node_modules/webpack/bin/webpack.js --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js --watch"

Update dependencies (extract lock files)

Composer lock: docker cp {{projectName}}:/var/www/composer.lock $PWD/composer.lock

Xdebug support

Even though the project runs inside a Docker container, it still provides support for debugging with Xdebug. By telling Xdebug the remote location of your IDE and configuring this one to listen to certain port, they can communicate with one another.

Use the XDEBUG_ environment variables to configure your project's debugging.

Xdebug for PhpStorm on Mac

Check this documentation, sections "Configuring PhpStorm" and "Configuring MacOS". to configure your IDE and system. Use the XDEBUG_ environment variables and the path mappings:

• "src" -> /var/www/src
• "vendor" -> /var/www/vendor