1. Getting Started with Rails

Question 1

What is Rails?

Answer 1

Rails is a web application development framework written in the Ruby language. Two major guiding principles: 1. don’t Repeat Yourself and 2. convention and over configuration:

Question 2

What is Rails?

Answer 2

Rails is a web application development framework written in the Ruby language. Two major guiding principles: 1. don’t Repeat Yourself and 2. convention and over configuration:

Question 3

controller’s purpose

Answer 3

to receive specific requests for the application.

Question 4

view’s purpose

Answer 4

display this information in a human readable format. view templates are written in a language called eRuby (Embedded Ruby)

Question 5

routing file

Answer 5

which holds entries in a special DSL (domain-specific language) that tells Rails how to connect incoming requests to controllers and actions

Question 6

resource

Answer 6

is the term used for a collection of similar objects, such as articles, people or animals. You can create, read, update and destroy items for a resource and these operations are referred to as CRUD operations.

Question 7

resources method

Answer 7

can be used to declare a standard REST resource.

Question 8

controller

Answer 8

is simply a class that is defined to inherit from ApplicationController. It’s inside this class that you’ll define methods that will become the actions for this controller. These actions will perform CRUD operations on the articles within our system. define an action inside a controller, all you need to do is to define a new method inside the controller.

Question 9

:formats in error message

Answer 9

specifies the format of template to be served in response. The default format is :html, and so Rails is looking for an HTML template.

Question 10

key, :handlers in error message

Answer 10

is telling us what template handlers could be used to render our template. :erb is most commonly used for HTML templates, :builder is used for XML templates, and :coffee uses CoffeeScript to build JavaScript templates.

Question 11

form_for

Answer 11

is a use a form builder. primary form builder for Rails is provided by a helper method called form_for.

<br>

When you call form_for, you pass it an identifying object for this form. In this case, it’s the symbol :article. FormBuilder object - represented by f - is used to build the form.

Question 12

form_for : pass :url option

Question 13

params method i

Answer 13

is the object which represents the parameters (or fields) coming in from the form. The params method returns an ActiveSupport::HashWithIndifferentAccess object, which allows you to access the keys of the hash using either strings or symbols.

Question 14

Models

Answer 14

in Rails use a singular name, and their corresponding database tables use a plural name.

Question 15

Migrations

Answer 15

are Ruby classes that are designed to make it simple to create and modify database tables.

Rails uses rake commands to run migrations, and it’s possible to undo a migration after it’s been applied to your database. Migration filenames include a timestamp to ensure that they’re processed in the order that they were created.

Question 16

strong parameters

Answer 16

requires us to tell Rails exactly which parameters are allowed into our controller actions. use controller parameters to prevent wrongful mass assignment. made private

Question 17

strong parameters

Answer 17

private
def article_params
params.require(:article).permit(:title, :text)
end

Question 18

frequent practice - CRUD operation order in controller

Answer 18

index, show, new, edit, create, update

and destroy.

Question 19

controller’s purpose

Answer 19

to receive specific requests for the application.

Question 20

view’s purpose

Answer 20

display this information in a human readable format. view templates are written in a language called eRuby (Embedded Ruby)

Question 21

routing file

Answer 21

which holds entries in a special DSL (domain-specific language) that tells Rails how to connect incoming requests to controllers and actions

Question 22

resource

Answer 22

is the term used for a collection of similar objects, such as articles, people or animals. You can create, read, update and destroy items for a resource and these operations are referred to as CRUD operations.

Question 23

resources method

Answer 23

can be used to declare a standard REST resource.

Question 24

controller

Answer 24

is simply a class that is defined to inherit from ApplicationController. It’s inside this class that you’ll define methods that will become the actions for this controller. These actions will perform CRUD operations on the articles within our system. define an action inside a controller, all you need to do is to define a new method inside the controller.

Question 25

:formats in error message

Answer 25

specifies the format of template to be served in response. The default format is :html, and so Rails is looking for an HTML template.

Question 26

key, :handlers in error message

Answer 26

is telling us what template handlers could be used to render our template. :erb is most commonly used for HTML templates, :builder is used for XML templates, and :coffee uses CoffeeScript to build JavaScript templates.

Question 27

form_for

Answer 27

is a use a form builder. primary form builder for Rails is provided by a helper method called form_for.

<br>

When you call form_for, you pass it an identifying object for this form. In this case, it’s the symbol :article. FormBuilder object - represented by f - is used to build the form.

Question 28

form_for : pass :url option

Question 29

params method i

Answer 29

is the object which represents the parameters (or fields) coming in from the form. The params method returns an ActiveSupport::HashWithIndifferentAccess object, which allows you to access the keys of the hash using either strings or symbols.

Question 30

Models

Answer 30

in Rails use a singular name, and their corresponding database tables use a plural name.

Question 31

Migrations

Answer 31

are Ruby classes that are designed to make it simple to create and modify database tables.

Rails uses rake commands to run migrations, and it’s possible to undo a migration after it’s been applied to your database. Migration filenames include a timestamp to ensure that they’re processed in the order that they were created.

Question 32

strong parameters

Answer 32

requires us to tell Rails exactly which parameters are allowed into our controller actions. use controller parameters to prevent wrongful mass assignment. made private

Question 33

strong parameters

Answer 33

private
def article_params
params.require(:article).permit(:title, :text)
end

Question 34

frequent practice - CRUD operation order in controller

Answer 34

index, show, new, edit, create, update

and destroy.