schutte_w4.md

Module 1 Week 4 Diagnostic

This exercise is intended to help you assess your progress with the concepts and techniques we've covered during the week.

For these questions, write a short description or snippet of code that meets the requirement. In cases where the question mentions a "given" data value, use the variable given to refer to it (instead of re-writing the information).

1. Give one difference between Modules and Classes.

Modules do not keep track of state/status, classes do (via instance variables).

2. Defining Modules

First, create a module Doughy which defines a method has_carbs? that always returns true.

module Doughy
  def has_carbs?
    true
  end
 end

Then, given the following Pizza class:

class Pizza
  def tasty?
    true
  end
end

Update Pizza to use your new Doughy module to gain the defined has_carbs? behavior.

class Pizza
  include Doughy
  def tasty?
    true
  end
end

pizza = Pizza.new
pizza.has_carbs?

3. More Modules

Given the following class and Module:

module Nonprofit
  def tax_exempt?
    true
  end
end

class Turing
end

Write code that enables the Turing class to use the Nonprofit module to allow the following behavior:

Turing.tax_exempt?
=> true

module Nonprofit
  def tax_exempt?
    true
  end
end

class Turing
  include Nonprofit
end

4. List 3 HTTP Verbs

GET, POST, and HEAD

5. HTTP Parsing

Given the following HTTP Request:

POST /students?name=horace HTTP/1.1
Host: 127.0.0.1:9292
Connection: keep-alive
Cache-Control: max-age=0
Accept: text/html
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8

Identify the:

1. HTTP Verb
2. Request Path
3. Query Parameters

1. POST
2. /students
3. ?name=horace

Additionally, give the full request URL:

127.0.0.1:9292/students?name=horace

6. Git and Branches

Give a git command to accomplish each of the following:

1. Switch to an existing branch iteration-1
2. Create a new branch iteration-2
3. Push a branch iteration-2 to a remote origin
4. Merge a branch iteration-1 into a branch master (assume you are not on master to begin with)

1. git checkout iteration-1
2. git branch iteration-2
3. (from iteration-2) git push origin master
4. git checkout master then git merge iteration-1

7. Load Paths and Requires

Given a project with the following directory structure:

. <you are here>
├── lib
│  │── file_one.rb
│  └── file_two.rb

Give 2 ways that we could require file_one from file_two.

1. require './lib/file_two'
2. require_relative '../lib/file_two'

8. Refactoring

Given the following snippet of code:

class Encryptor
  def date_offset
    date = Time.now.strftime("%d%m%y").to_i
    date_squared = date ** 2
    last_four_digits = date_squared.to_s[-4..-1]
    [last_four_digits[-4].to_i,
     last_four_digits[-3].to_i,
	 last_four_digits[-2].to_i,
	 last_four_digits[-1].to_i]
  end
end

Encryptor.new.date_offset

Show 2 refactorings you might make to improve the design of this code.

class Encryptor
  def date_offset
    date = Time.now.strftime("%d%m%y").to_i
    date_squared = date ** 2
    last_four_digits = date_squared.to_s[-4..-1]
    last_four_digits.chars.map(&:to_i)
  end
end

Encryptor.new.date_offset

class Encryptor
  def date_offset
    date = (Time.now.strftime("%d%m%y").to_i) ** 2
    date.to_s[-4..-1].chars.map(&:to_i)
  end
end

Encryptor.new.date_offset