Chapter 3

Question 1

where are rails actions?

Answer 1

in the controller

Question 2

switch to branch “static-pages”

Answer 2

git checkout -b static-pages

Question 3

how can we generate a controller?

Answer 3

rails generate command to generate scaffolding

Question 4

steps to make a controller to handle static pages

Answer 4

create StaticPages controller using generate. plan to make actions for home page, help page and about page.
$ rails generate controller StaticPages home help

Question 5

$ rails generate conroller StaticPages home help

Answer 5

generates StaticPages controller with actions for home and help

Question 6

scaffolding

Answer 6

generate major pieces of an application to create models, views, and controllers for a new resource

Question 7

rails g

Answer 7

rails generate shortcut

Question 8

rails c

Answer 8

rails console shortcut

Question 9

bundle install

Answer 9

bundle shortcut

Question 10

rake test

Answer 10

rake shortcut

Question 11

git push -u origin static-pages

Answer 11

pushes topic branch up to github

Question 12

destroy controller StaticPages:

Answer 12

rails destroy controller StaticPages home help

Question 13

generate a model using scafffolding

Answer 13

rails generate model User name:string email:string

Question 14

undo model generated User

Answer 14

rails destroy model User

Question 15

bundle exec rake db:migrate

Answer 15

change the state of the database

Question 16

undo db:migrate

Answer 16

bundle exec rake db:rollback (undo a single migration)

Question 17

route file

Answer 17

responsible for implementing the router(defining the correspondence between URLs and web pages).

Question 18

get ‘static_pages/home’

Answer 18

located in cofig: maps requests for the URL /static_pages/home to the home action in the Static Pages controller.

Question 19

get ‘static_pages/home’ what is get

Answer 19

using get we arrange the route to respond to a GET request, HTTP

Question 20

http

Answer 20

basic operations get, post, patch, and delete. operations between a client(chrome firefox) and a server(apache or nginx). emphasis on http verbs is typical of web frameworks influenced by the rest architecture.

Question 21

get method

Answer 21

reading data on the web. just means ‘get a page’. everytime you visit google your browser submits a get request

Question 22

post method

Answer 22

request sent by your browser when you submit a form. in rails, post are typically used for creating things(http also allows post to perform updates.

Question 23

patch method

Answer 23

updating things on remote server

Question 24

delete mthod

Answer 24

destroy things on remote server

Question 25

classes in rails

Answer 25

organize functions like home and help action which are defined using def keyword

Question 26

def home
end
in ruby this method is empty. is that true for Rails?

Answer 26

because it inherits ApplicationController the behavior of its methods is specific to rails. when visitin th url, rails executes the code inthe method AND renders the view. if method is empty, all it does is render the view.

Question 27

TDD

Answer 27

test-driven development, programmers writes failing tests first, and then writes the application code to get the tests to pass

Question 28

benefits of testing

Answer 28

1. protects against regressions where a functioning feature stops working for some reason
2. test allow code to be refactored(changing its form without changing its function)
3. tests act as a client for the application code helping determine its design and its interface

Question 29

when to test first(or test at all)

Answer 29

1. if test is short compared to code, write test first
2. when desired behavior of app isnt clear, write application code first.
3. because security is a top priority, write test for security model first
4. whenever a bug is found, write a test to reproduce it and protect against regressions, then write the code to fix it.
5. against writing test code for html structure
6. write tests before refactoring code

–usually write controller and model tests first and integration tests(functionality) second

Question 30

test “should get home” do
get :home
assert_response :success
end

Answer 30

lets test the home page by using get request to the home action and then making sure we receive a success status code in response

Question 31

run test suite to verify tests currently pass

Answer 31

bundle exec rake test

Question 32

ActionController::UrlGenerationError:

No route matches {:action=>”about”, :controller=>”static_pages”}

Answer 32

no route matches the desired action/controller combination which is a hind that we need to add a line to the routes file

Question 33

AbstractController::ActionNotFound:

The action ‘about’ could not be found for StaticPagesController

Answer 33

missing about action in static pages controller, which we can add

Question 34

ActionView::MissingTemplate: Missing template static_pages/about

Answer 34

indicates a missing template, which in the context of rails is essentially the same thing as a view.

Question 35

touch app/views/static_pages/about.html.erb

Answer 35

although touch is designed to update the modification of a file or directory without otherwise affecting it, as a die-effect it creates a new file if one doesnt exist

Question 36

assert_select “title”, “Home | Ruby on Rails Tutorial Sample App”

Answer 36

checks for the presence of a tag containing the string.

Question 37

DRY

Answer 37

Dont Repeat Yourself principle: our html paes contained almost identical titles, common parts to all three, and an entire HTML skeleton structure is repeated on each page. we’ll DRY out our code by removing repitition

Question 38

ERb

Answer 38

embedded ruby, primary template system for including dynamic content in web pages

Question 39

rails function provide fr titles

Answer 39

special rails function to set different titles on each page

Answer 40

indicates using that rails should call the provide function and associate the string “Home” with the label :title, then we use yield funtion in ruby to insert the title into the template

Question 41

Ruby on Rails Tutorial Sample App

Answer 41

insert title label string into parts of html code

Answer 42

responsible for inserting the contents of each page into the layout. converts the contents of home.html.erb to HTML and then inserts it in place of

Question 43

csrf_meta_tags

Answer 43

prevents cross-site request forgery (CSRF), a type of malicious web attack

Question 44

purpose of rails layout

Answer 44

allow the use of a common template for pages in our application, thereby eliminating duplication