Docker.

docker-compose up

Starts a PHP and MySQL container on localhost (127.0.0.1) at ports 80 and 3306 respectively. Some basic test data is loaded automatically.

The entire system can be refreshed using:

docker-compose down

And then starting it back up again.

All data is returned as JSON. The endpoints are implemented in src/index.php.

• GET / Returns a listing of all jobs
• GET /job Returns the highest priority job, the next job to be processed
• GET /job/$id Returns the job with the specified ID
• GET /process Processes the highest priority job
• GET /process/$id Processes (or re-processes) the job with the specified ID
• GET /users Lists all users
• GET /user/$id Returns the specified user and all their jobs
• POST /job Adds a new job (params: cmd, priority, user_id)
• POST /register Registers a new user (params: name)

The attached System Diagram illustrates a basic scalable distributed system.

This design can be further scaled by:

• Separating the API servers into read/write servers
• Adding load balancers in front of the API servers
• Implementing some form of key:value memory caching for read accesses with a least recently used eviction policy