dacamp / interview

A project for interviewing Ruby & Rails developers

Interview

This project serves to evaluate developers' proficiency in Ruby & Rails.

How Does It Help?

Interviees are expected to clone this project and enter its interactive console for two types of tests:

1. Read a piece of code, and name the returned value by evaluating the code.
2. Read the specifications, and write a method to fulfill the specs.

Also, start the rails server if the they are expected to debug several Rails problems. Interviers can sit by the interviewees to see how they handle the problems.

The interactive console looks like this:

Ready for the Interview?

Installation

Clone:

git clone https://github.com/adlerhsieh/interview.git
cd interview

Setup:

bundle install

Part 1: Name the Returned Value

Run:

rake questions

which brings you to an interactive console. You will see several pieces of code. Input the returned values for each code piece. Type Exception if you expect an exception.

Other commands:

1. Use exit to exit.
2. Use skip to skip a question.

Part 2: Write a Method

Run:

rake methods

which brings you to another interactive console. Write methods in one line and fulfill the instructions.

Each submission triggers rspec to run tests against the submitted code. Make them pass to move on to the next method.

Other commands:

1. Use exit to exit.
2. Use skip to skip a method.

Part 3: Debugging Rails

Setting up db is necessary for this part. Run:

rake db:migrate
rake db:seed

Start rails server and open root / in the browser. The interviewee should solve these problems:

1. The posts should display a default avatar, which is their authors' first character of their name. They are missing. Fix it.
2. Enter the post with (Slow Post) text. It reveals the performance issue for this app. Don't modify the layout and improve its performance.
3. When creating a Post with the New post button, the content is always blank. Make sure the content is correctly displayed in posts#show.

Other Interview Stuff

1. Some common Interview Questions
2. The whole test takes about 1.5 hour based on my experience. It is suggested that interviers only assign necessary tests.

Customization

Questions and methods are customizable in lib directories. They follow a simple set of rules.

Questions

Add files in lib/questions directory. Name the file 0, 1, 2 and so on. Every file will be process in order of their filename.

Do not add too many blank lines around the code. They will be displayed too.

Example:

a = 'foo'
b = 'bar'

a + b

If the filename is lib/questions/0.rb, it will be processed as the first question.

Methods

Code

Add files in lib/questions directory.The specifications are:

1. Name the file 0, 1, 2 and so on. Every file will be process in order of their filename.
2. Each file is written with 2 parts: instruction and method. Intsruction describes the purpose of this method, and method is for the interviewee to understand where the code is inserted.
3. Use # method to separate instructions and method.
4. Use # code to indicate which part the interviewees' code are inserted.
5. You can either comment out instructions or not. They will not be evaluated.

Example:

# Create a method that returns the sum of x and y.
# 
# Example: 
# 
#     plus(1, 1)
#     # => 2
#     plus(2, 3)
#     # => 5
#     plus(5, 5)
#     # => 10

# method
def plus(x, y)
  # code
end

Spec

Also, this project implements RSpec as the test framework. You need to add specs in spec/lib/methods in order to make sure interviewees' methods fulfill a specific standard.

Please add require 'interview_helper' at the beginning of every spec file.

Example:

require 'interview_helper'

describe '#plus' do
  it { expect(plus(1, 1)).to eq 2 }
  it { expect(plus(2, 3)).to eq 5 }
  it { expect(plus(5, 5)).to eq 10 }
end

Pull requests and issues are welcome