README

Welcome to the Gilded Rose Magickal Emporium! Or, more accurately, welcome to its inventory system.

Here at the Gilded Rose we buy and sell only the finest goods. Unfortunately, our goods are constantly degrading in quality as they approach their sell by date. We have a system in place that updates our inventory for us. The original developer of that system has since moved on to new adventures.

Getting Started

bin/setup
bin/rake

An introduction to our system

• All items have a sell_in value which denotes the number of days we have to sell the item
• All items have a quality value which denotes how valuable the item is
• At the end of each day our system lowers both values for every item

As the Gilded Rose offered more inventory, we ran into a few exceptions that we quickly updated the system to accommodate:

• Once the sell by date has passed, quality degrades twice as fast
• The quality of an item is never negative
• "Aged Brie" actually increases in quality the older it gets
• The quality of an item is never more than 50
• "Sulfuras", being a legendary item, never has to be sold or decreases in quality
• "Backstage pass", like aged brie, increase in quality as time passes; quality increases by 2 when there are 10 days or less until the concert date, and by 3 when there are 5 days or less, but quality drops to 0 after the concert

Just for clarification, an item can never have its quality increase above 50, however "Sulfuras" is a legendary item and as such its quality is 80 and it never alters.

Nightly system updates

We run a nightly ActiveJob to change quality and sell_in, jobs/nightly_quality_update_job.rb. It works by fanning out a number of other queued jobs that we can run in a highly parallelized manner.

DO NOT MODIFY THE DATABASE SCHEMA

The database schema stores the sell_in value as a time remaining integer.
Please don't change the database schema! Both our brick-and-mortar stores and our database servers are geographically located in the UMC (Coordinated Universal Magical Time) timezone, which as you know has inconsistent interactions with both Ruby and Rails core. Previous changes to the database schema had unpleasant side effects, so all schema changes are now forbidden.

Your task

We have recently signed a supplier of conjured items. "Conjured" items degrade in quality twice as fast as normal items.

We're currently only carrying "Conjured Mana Cakes", and don't anticipate expanding our Conjured line of items in your lifetime. Since it's such a simple task and we don't anticipate changes for a long time, we're allocating 10 minutes for you to deliver this feature.

Your next task

Great news! our sales rep just came through for us, and we'll be supplying our stores with all manner of Conjured items!

Your task is to support all "Conjured" items in our inventory system so that we can begin selling this exciting new category of items.

Credits

Gilded Rose on Rails was created by Betsy Haibel, but it wouldn't exist without

• Jim Weirich's Ruby version
• based on the original C# version
• Sandi Metz's POOD course, and her book with Katrina Owen, 99 Bottles of Oop

We are tremendously grateful for those who came before us and led the way, and also to the brave handful of people who enthusiastically allowed us to lead them through the problem in its earlier stages.