The purpose of this task is to create a method of examining a social network. You are given data (data.json) representing a group of people, in the form of a social graph. Each person listed has one or more connections within the group.
Come up with a data structure to store and query the information found in the JSON file.
You should then create a public API in the language of your choice which allows for three basic operations to be executed for a certain person:
- Direct friends: Return those people who are directly connected to the chosen person.
- Friends of friends: Return those who are two steps away, but not directly connected to the chosen person.
- Suggested friends: Return people in the group who know 2 or more direct friends of the chosen person, but are not directly connected to her.
Your API can be exposed as public functions, a REST-endpoint, a command line interface, whatever fits the choice of your technology stack best.
- Requirements
- Installation
- Running application
- Insepecting API from console
- Running tests
- Additional notes
- PHP >= 5.4
- MCrypt PHP Extension
- MySQL
- Composer globally installed
- Bower globally installed
- PHPUnit
- Clone repo with
git clone git@github.com:milosh012/social-graph.git - Install PHP deps with (from the root of the project)
composer install - Install JS deps with
bower install - Create DB in MySQL with name "socialgraph"
- Setup mysql configuration in
app/config/database.php(host, username, password, db... 57 - 60 lines) - Run migrations
php artisan migrate - Seed DB with fixtures
php artisan db:seed
Open console and from the root of the project run small server with
php artisan serve and go to http://localhost:8000
After running application server, you can send API requests with CURL:
- Get all users (GET: /users)
curl 'http://localhost:8000/users' -H 'Pragma: no-cache' -H 'Accept: application/json, text/plain, */*'
- Get user friends (GET /users/{id}/friends)
curl 'http://localhost:8000/users/1/friends' -H 'Pragma: no-cache' -H 'Accept: application/json, text/plain, */*'
- Get user friends of friends (GET /users/{id}/friends-of-friends)
curl 'http://localhost:8000/users/1/friends-of-friends' -H 'Pragma: no-cache' -H 'Accept: application/json, text/plain, */*'
- Get suggested friends (GET /users/{id}/suggested-friends)
curl 'http://localhost:8000/users/16/suggested-friends' -H 'Pragma: no-cache' -H 'Accept: application/json, text/plain, */*'
To run all tests you will need to have PHPUnit installed.
Navigate to the root of the project and then run phpunit
To run only unit tests you need to specify group: phpunit --group=unit
To run only integration tests you need to specify group: phpunit --group=integration
This is just a development setup and environment. If we want to deploy this on production then we must do some additional steps:
- Combine and minimize all CSS files
- Combine and minimize all JS files (maybe we can have 2 files - one for external libs and one for application itself)
- Put revision number into CSS and JS files names to prevent browser caching on new deploy
For all above tasks I usually use Gulp tool.
Also, I think that the best type of DB for this kind of application is Graph DB (for example Neo4j). I didn't implemented here Neo4j because I never used this in real life (just reading about it).
But with a current project structure it is very easy to change Repository provider to use Neo4j.
In app/routes.php file we need to change just 2 lines
App::bind('Repositories\FriendRepositoryInterface', 'Repositories\EloquentFriendRepository');
App::bind('Repositories\UserRepositoryInterface', 'Repositories\EloquentUserRepository');
to become
App::bind('Repositories\FriendRepositoryInterface', 'Repositories\Neo4jFriendRepository');
App::bind('Repositories\UserRepositoryInterface', 'Repositories\Neo4jUserRepository');
And of course to create that 2 classes and write unit tests for them.