Intro

We are building a Ruby on Rails app that will update our database to match the data our clients provide in CSV format on a daily basis.

The objective is to code the CSV import and handle some specific update rules.

Lets consider that the app manages 2 models (all their attributes are strings):

Person with the following attributes : reference, email, home_phone_number, mobile_phone_number, firstname, lastname, address
Building with the following attributes : reference, address, zip_code, city, country, manager_name

Do not use third party gems in your solution

Step 0

✔️ Create a new Ruby on Rails project and create the models.

rails new inch
cd inch
rails g model Person reference:string email:string home_phone_number:string mobile_phone_number:string firstname:string lastname:string address:string
rails g model Building reference:string address:string zip_code:string city:string country:string manager_name:string

Step 1

✔️ Implement the import feature that takes a given csv file and creates/updates (no need to handle deletions) the records of the corresponding table to match the data in the csv.

Example csv files are provided below to help you understand the input format; you'll have to create more when writing your tests.

Note: In the example files, there are only 2 lines per csv, but in reality there can be millions of records to import each day (do not neglect performance).

Step 2

Some attributes have to respect specific rules regarding the update of their value :

The considered attributes should be overwritten by the csv import only if the value provided in the csv has never been a value of that field.
In parallel to updates made by the csv imports, the users of our application can also update the records on a provided user interface (no need to develop that interface). A manual update should always succeed.

The attributes that must respect these rules are the following (all the other attributes must match the csv):

for the Person model : email, home_phone_number, mobile_phone_number and address
for the Building model : manager_name

✔️ Make the necessary changes to your code to handle these rules.

Evaluation

We will closely watch the following criteria for the evaluation:

The readability of the code (how easily we can understand what you did)
The flexibility of the code (how easy it would be to extend the features)
The global performance of the import (we don't need a rocket, but not a turtle either. We will not evaluate the performance of the CSV parsing lib, use the default ruby CSV parsing lib)
The testing of your code (use RSpec or any other testing framework that you're used to)

gmonein/InchTechTest