rails5.md

http://guides.rubyonrails.org/getting_started.html

STEP 1 create new project (creates scaffolding)

$ rails new JMDMega

$ bin/rails server--> Check localhost:3000 -> Stop ctrl +C

STEP 2 create a controller, an action, a view, 2 routes,

$ bin/rails generate controller Welcome index

creates: welcome_controller, index function, index.html.erb,(welcome/index, default route)

<\app\controller\action_controller.rb>

class ApplicationController < ActionController::Base 
end

<\app\controller\welcome_controller.rb>

class WelcomeController<ApplicationController
     def index; end; end

<\view\welcome\index.html.erb> <h1>Hello, Rails!</h1> the first extension is the format of the template, the second extension is the handler that will be used to render the template.

<\config\routes>

       Rails.application.routes.draw  do
           get 'welcome/index'
           root 'welcome#index'

STEP 3 Adding a resource route -collection of similar objects- articles

<\config\routes.rb> - add resource: :articles --> this creates API CRUD routes

$bin/rails routes

route Verb	URI	Action
root GET	/	welcome#index
welcome_index GET	/welcome/index(.:format)	welcome#index
.	articles GET	/articles(.:format)
.	POST	/articles(.:format)
.	new_article GET	/articles/new(.:format)
edit_article GET	/articles/:id/edit(.:format)	articles#edit

article GET   |   /articles/:id(.:format)  |    articles#show|

STEP 4 Adding resource Controller

  $ bin/rails generate controller Articles

STEP 5 Adding resource View

create a new file at app/views/articles/new.html.erb

<h1>New Article<h1>

STEP 6 The first form

To create a form within this template, you will use a form builder. The primary form builder for Rails is provided by a helper method called form_with. The form needs to use a different URL in order to go somewhere else. This can be done quite simply with the :url option of form_with.

<%= form_with scope: :article, url: articles_path, local: true do |form| %>

STEP 7 Adding actions in Controller

def create ; render plain: params[:article].inspect ; end

STEP 8 Creating the Article model

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

$ bin/rails generate model Article title:string text:text

app/models/article.rb and db/migrate/20140120191729_create_articles.rb

class CreateArticles < ActiveRecord::Migration[5.0]
  def change
    create_table :articles do |t|
      t.string :title
      t.text :text
   t.timestamps

Migrations 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 are processed in the order that they were created.

STEP 8 5.5 Running a Migration

$ bin/rails db:migrate
==  CreateArticles: migrating ==================================================
-- create_table(:articles)
   -> 0.0019s
==  CreateArticles: migrated (0.0020s) =========================================

STEP 9 Saving data in controller

def create
  @article = Article.new(params[:article])
      #/ attritube mapped to respective db model
      #/ class named Article that is defined in app/models/article.rb.
      
  @article.save         #/ returns boolean-the article was saved or not.
  redirect_to @article    #/ show action, which we'll define later
end

STEP 10 Security feature: strong parameters, which requires us to tell

Rails exactly which parameters are allowed into our controller actions. #articles_controller.rb

@article = Article.new(article_params)

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

STEP 11 Showing Articles

TODO

5.11 Updating Articles

We've covered the "CR" part of CRUD. Now let's focus on the "U" part, updating articles. TODO

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MM- MVCR app
rails new project (creates defaults), 
1. Welcome Page- CVR- no Model
`generate controller Welcome index`  
add action index (), create <index.html.erb> View "<h1>Hello, Rails!</h1>",  
add <config\routes.rb> `get 'welcome/index' `
 
  resources :articles, root route)

2. route add `resource: :articles` (creates CRUD API routes)
`generate controller Articles `, <new.html.erb> View "New Art",
create form- view Articles using form_with
create action- #create
generate model Article title:string text:text

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Output of $ bin/rails generate controller Welcome index
Running via Spring preloader in process 45551
      create  app/controllers/welcome_controller.rb
       route  get 'welcome/index'
      invoke  erb
      create    app/views/welcome
      create    app/views/welcome/index.html.erb
      invoke  test_unit
      create    test/controllers/welcome_controller_test.rb
      invoke  helper
      create    app/helpers/welcome_helper.rb
      invoke    test_unit
      invoke  assets
      invoke    coffee
      create      app/assets/javascripts/welcome.coffee
      invoke    scss
      create      app/assets/stylesheets/welcome.scss

$ bin/rails generate controller Articles
Running via Spring preloader in process 2146
      create  app/controllers/articles_controller.rb
      invoke  erb
      create    app/views/articles
      invoke  test_unit
      create    test/controllers/articles_controller_test.rb
      invoke  helper
      create    app/helpers/articles_helper.rb
      invoke    test_unit
      invoke  assets
      invoke    coffee
      create      app/assets/javascripts/articles.coffee
      invoke    scss
      create      app/assets/stylesheets/articles.scss

      $ Generate scaffolding User name:string

codeami/rails5.md