Ruby

Front 1

Polymorphism

Back 1

Code that can work with objects of multiple types and classes at once.

Front 2

Give an example of a polymorphic method in Ruby.

Back 2

#to_s works on integers, arrays, and hashes.

Front 3

What is a private method in Ruby?

Back 3

Methods marked private are only accessible by code inside an object's methods. You can't call them directly on an object.

Front 4

Describe a protected method in Ruby.

Back 4

A protected method can be called from the scope of the methods of any object that's a member of the same class.

Front 5

Define Class in Ruby.

Back 5

A class is a blueprint for creating objects.

Front 6

Define Object in Ruby.

Back 6

An object is an instance of a class, something built from the class blueprint.

Front 7

Define local variable in Ruby.

Back 7

A variable that can only be used in the same place it is defined.

Front 8

How do you define a global variable in Ruby.

Back 8

$variable_name

Front 9

Define object or instance variable in Ruby.

Back 9

Variables that have scope within and are associated to the current object.

Front 10

Define global variable in Ruby.

Back 10

Variables that are accessible from everywhere within an application.

Front 11

Define class variables in Ruby.

Back 11

Variables whose scope is within the current class as opposed to within specific objects of that class.

Front 12

Define reflection in Ruby.

Back 12

The process by which a computer program can inspect analyze and modify itself while it's running and being used.

Front 13

Define Module in Ruby.

Back 13

A structure to collect classes, methods, and constants into a single, separately named and defined unit.

Front 14

Explain the difference between a class and a module in Ruby.

Back 14

Modules are namespaced methods and constants (like libraries). Whenever you want code that logically belongs together but that won’t require that you create instances of a ‘model’, then a module is the right construct to use.

Front 15

How do you declare and use a constructor in Ruby?

Back 15

class Beer

def initialize(style)

@style = style

end

end

ipa = Beer.new(ipa)

"new" is the constructor in Ruby

Front 16

How do you create a getter method in Ruby?

Back 16

class Beer

attr_reader :style

end

which is a shortcut for:

def style

@style

end

Front 17

How do you create a setter method in Ruby?

Back 17

class Beer

attr_writer :style

end

which is a shortcut for:

def style=(value)

@style = value

end

Front 18

Name 3 ways to invoke a method in Ruby?

Back 18

beer = Beer.new

1. beer.some_method

2. beer.send(:some_method)

3. beer.method(:some_method).call *Not sure this one is correct.

Front 19

Explain what 'self' means in Ruby.

Back 19

x

Front 20

Explain why they say almost everything is an object in Ruby.

Back 20

x

Front 21

What is a singleton method in Ruby?

Back 21

x

Front 22

Describe the Ruby method lookup path.

Back 22

x

Front 23

List Ruby callback (functions?). How are they used?

Back 23

x

Front 24

What is Rack?

Back 24

x

Front 25

Explain the Rack application interface.

Back 25

x

Front 26

Write a simple Rack application.

Back 26

x

Front 27

How does Rack middleware work?

Back 27

x

Front 28

Define middleware.

Back 28

x

Front 29

What are Ruby gems? How do they work?

Back 29

x

Front 30

Explain the structure of a Ruby gem.

Back 30

x

Front 31

Give some examples of your favorite gems.

Back 31

x

Front 32

What is ActiveJob? When should you use it?

Back 32

x

Front 33

What is the Asset Pipeline?

Back 33

The asset pipeline provides a framework to concatenate and minify or compress JavaScript and CSS assets. It also adds the ability to write these assets in other languages and pre-processors such as CoffeeScript, Sass and ERB.

Front 34

Explain the difference between a symbol and a string in Ruby. Why would you use one over the other?

Back 34

x

Front 35

Explain the difference between Page, Action, Fragment, Low-level, and SQL caching types.

Back 35

x

Front 36

What is RailsEngine? (WTF is Rails Engine?)

Back 36

x

Front 37

Describe the different types of association relationships that exist? (Where? In what? WTF is this referring to?)

Back 37

x

Front 38

What is the directory structure of Rails?

Back 38

x

Front 39

What is the main function of helpers?

Back 39

x

Front 40

What is garbage collection? Why use it?

Back 40

x

Front 41

Give an example of RESTful routing and controllers.

Back 41

x

Front 42

Describe the CRUD verbs and actions.

Back 42

x

Front 43

How should you test routes?

Back 43

x

Front 44

How do you use filters in controllers?

Back 44

x

Front 45

What are strong parameters?

Back 45

A set of approved, white-listed attributes that can be assigned when creating and updating an object in Rails.

Front 46

What should you test in controllers?

Back 46

x

Front 47

How do you use content_for and yield?

Back 47

x

Front 48

How should you use nested layouts?

Back 48

x

Front 49

Explain the Active Record pattern.

Back 49

x

Front 50

What is Object-Relational Mapping (ORM)?

Back 50

x

Front 51

Describe Active Record conventions.

Back 51

x

Front 52

Explain the migrations mechanism (in Active Record or Rails in general?)

Back 52

x

Front 53

What are the the types of associations in Active Record?

Back 53

x

Front 54

What is Scopes (in Active Record? WTF?). How should you use it? *This is how the question is asked from the blog site you're looking at.

Back 54

x

Front 55

Explain the difference between optimistic and pessimistic locking in Active Record.

Back 55

x

Front 56

Explain the concept of sessions in a web application. How does it work?

Back 56

x

Front 57

Describe cross-site request forgery.

Back 57

CSRF stands for Cross-Site Request Forgery. This is a form of an attack where the attacker submits a form on your behalf to a different website, potentially causing damage or revealing sensitive information. Since browsers will automatically include cookies for a domain on a request, if you were recently logged in to the target site, the attacker’s request will appear to come from you as a logged-in user (as your session cookie will be sent with the POST request).

Front 58

Describe cross-site scripting.

Back 58

Cross-Site Scripting (XSS) attacks are a type of injection, in which malicious scripts are injected into otherwise benign and trusted web sites. XSS attacks occur when an attacker uses a web application to send malicious code, generally in the form of a browser side script, to a different end user.

Front 59

Describe session hacking and session fixation attacks.

Back 59

x

Front 60

What's the difference between SQL injection and CSS injection?

Back 60

x

Front 61

How should you store secure data (e.g. passwords)?

Back 61

x

Front 62

Explain the significance of using HTTPS vs. HTTP.

Back 62

x

Front 63

What is a code smell?

Back 63

A piece of code or pattern that goes against conventional practices, or implements bad coding practices.

Front 64

What are some good tools to find code smells and bugs?

Back 64

x

Front 65

Why should you avoid fat controllers?

Back 65

DRY code and the principle of single responsibility in methods. Easier to read, maintain, and update.

Front 66

Why should you avoid fat models?

Back 66

DRY code and the principle of single responsibility in methods. Easier to read, maintain, and update.

Front 67

Explain extract value, service, form, view, query, and policy objects techniques. (WTF?)

Back 67

x

Front 68

Why did you become a programmer?

Back 68

I like the opportunity it provides to combine both my creative and analytical sides.

Front 69

What project are you most proud of?

Back 69

print.nookpress.com

Front 70

What is the difference between Ruby's Hash and ActiveSupport's HashWithIndifferentAccess?

Back 70

Ruby's Hash class does a key lookup using == method. This means that a key of :whiskey_tango DOES NOT equal the string key "whiskey_tango". HashWithIndifferentAccess ignores this difference, equating symbols to their string counterparts.

Front 71

How can you defend against a CSRF attack in Rails?

Back 71

protect_from_forgery with: :exception in the application controller. This ensures a request that fails the authenticity token check does not execute.

Front 72

What is the difference between a member route and a collection route in Rails?

Back 72

A member route requires an id because it acts on a specific member of a collection. A collection route does not require an id because it acts on the collection as a whole. Think #show (member route) vs. #index (collection route).

Front 73

Define mutable object

Back 73

A mutable object can be changed (it's value) after assignment. A string is a mutable object in Ruby.

Front 74

Define immutable object

Back 74

An immutable object cannot be changed after assignment; it can only be overwritten. A symbol is an immutable object in Ruby.

Front 75

True or False? A string in Ruby requires a new space in memory every time it is written.

Back 75

True

Front 76

True or False? A symbol in Ruby requires a new space in memory every time it is written.

Back 76

False

Front 77

List the 7 RESTful routing actions, their corresponding HTTP verbs in Rails, and sample urls for a 'photos' resource.

Back 77

1. Index => GET => /photos

2. New => GET => /photos/new

3. Create => POST => /photos

4. Show => GET => /photos/:id

5. Edit => GET => /photos/:id/edit

6. Update => PATCH/PUT => /photos/:id

7. Destroy => DELETE => /photos/:id

Front 78

Define Mixin in Ruby

Back 78

A Mixin is the point of insertion for a Module in Ruby. You can either 'include' the Mixin or 'extend' it into a class.

Front 79

Explain the difference between using the include keyword versus the extends keyword when adding a Mixin to your Ruby classes.

Back 79

1. The include keyword adds the methods of the module to the class as instance methods.

2. The extends keyword adds the methods of the module to the class as class methods.

Front 80

What is a remote repository?

Back 80

Remote repositories are versions of your project that are hosted on the Internet or network somewhere.

Front 81

Define Object Oriented Programming.

Back 81

Paradigm that models programs around objects, with attributes and behavior, rather than a set of procedural steps.

Front 82

What is duck typing?

Back 82

When a language is less concerned with an object's type (i.e. its Class) and more with what it can do. In Ruby, if an object walks like a duck and quacks like a duck, the Ruby interpreter is happy to treat it like a duck.

Front 83

Define a dynamically typed language.

Back 83

a programming language where the type of a variable can change and be resolved on the fly at the exact moment it gets parsed by the interpreter.

Front 84

Define a statically typed language.

Back 84

language where the type of a variable is resolved in advance by the interpreter/compiler. With statically typed languages, you cannot say that x is a string and, a few lines after, that it is an integer.

Front 85

True or False: Ruby is a statically typed programming language.

Back 85

FALSE. Ruby is a dynamically typed programming language.

Front 86

Define a Strongly Typed programming language.

Back 86

A language in which once a variable's type is defined, it will only allow certain things to be done with it.

Front 87

Define a Weakly Typed programming language.

Back 87

A language that allows you to mix and match variable types in your expressions without throwing an exception.

Front 88

What is a session in Rails?

Back 88

x

Front 89

Who designed the Ruby language?

Back 89

Yukihiro Matsumoto.

Front 90

Who developed Rails?

Back 90

David Heinemeier Hansson

Front 91

How would your current manager rate your performance on a scale from 1 to 10?

Back 91

x

Front 92

Has your recent manager mentioned any specific areas that you need to improve on? *Note that this is a different wording of the 'What is/are your weaknesses?'

Back 92

x

Front 93

What are some good things your current manager (or any reference you list) would say about you? *Note that this is a different wording of 'What are your strengths?'

Back 93

x

Front 94

What are your strengths?

Back 94

x

Front 95

What are your weaknesses?

Back 95

x

Front 96

True or False. Model names in Rails are singular.

Back 96

True.

Front 97

True or False. Controller names in Rails are plural.

Back 97

True.

Front 98

True or False. Database table names in Rails are plural and begin with a lower case letter.

Back 98

True.

Front 99

True or False. The #create method for an Active Record model immediately updates the database.

Back 99

True.

Front 100

True or False. The #new method for an Active Record model immediately updates the database.

Back 100

False. After assigning attributes to a model using the #new method you must use model#save to update the db.

Front 101

Describe the strong parameters pattern for an instance of article, using the attributes title and category.

Back 101

private

def article_params

params.require(:article).permit(:title, :category)

end

Front 102

x

Back 102

x

Front 103

What are partials used for in Rails?

Back 103

partials are used to extract away redundant view code into component-like, re-usable chunks.

Front 104

Describe the differences between unit, functional, and integration tests in Rails.

Back 104

x