rishiip

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

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What's a Hash and why is it important?

A Hash is a collection of key-value pairs. To add, fetch, modify, and delete a value from a Hash, you refer to it with a unique key.

While an Array is indexed by Integers only, a Hash is keyed by any object -- Strings, Integers, etc.

In other programming languages, a Hash might be known as an 'associative array', 'dictionary', or 'HashMap'.

What does a Hash look like?

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class Api::RegistrationsController < Api::BaseController
  
  respond_to :json
  def create

    user = User.new(params[:user])
    if user.save
      render :json=> user.as_json(:auth_token=>user.authentication_token, :email=>user.email), :status=>201
      return
    else

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Create the partition:

sgdisk --zap-all /dev/sda
cgdisk /dev/sda
mkfs.ext4 /dev/sda1
mount /dev/sda1 /mnt

Edit the mirror list to bring the preferred mirror to the top:

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require 'webrick'
 
Port = 3000
Directory = Dir::pwd

WEBrick::HTTPServer.new(
	Port: Port,
	DocumentRoot: Directory
).start

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# nil? can be used on any Ruby object. It returns true only if the object is nil.
nil.nil?   # => true 
[].nil?    # => false 
{}.nil?    # => false
"".nil?    # => false
" ".nil?   # => false
true.nil?  # => false

# empty? can be used on some Ruby objects including Arrays, Hashes and Strings. It returns true only if the object's length is zero.
nil.empty?   # NoMethodError: undefined method `empty?' for nil:NilClass

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# RSpec allows us to test private methods of a model.

for example, 

class User
  def is_active?
    true
  end
  private :is_active?
end

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Save below code to `bson.rb` file within `config/initializers` directory and restart the server

module BSON
  class ObjectId
    def as_json(*args)
      to_s
    end
  end
end

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{
   "AP":[
      "Adilabad",
      "Anantapur",
      "Chittoor",
      "Kakinada",
      "Guntur",
      "Hyderabad",
      "Karimnagar",
      "Khammam",

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#!/bin/bash
sudo apt-get update

# To make sure we have everything necessary for Webpacker support in Rails, we're first going to start by adding the Node.js and Yarn repositories to our system before installing them.

sudo apt-get install curl
curl -sL https://deb.nodesource.com/setup_8.x | sudo -E bash -
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
sudo apt-get update