Week 2, Day 4

til.txt

string is the default for data type when creating attributes for a model

rails generate model Product name price:integer image_url description     <-- all attributes of model Product will be strings except price (integer)


1. WEB REQUEST                                                                     WINDOW ORDER
2. API ROUTE                                                      DESKTOP   CHROME    SUBLIME   TERMINAL    SLACK
3. API CONTROLLER (gets data from MODEL)  <-- subject for today
4. JSON VIEW
5. WEB RESPONSE
                                    
rails new mini_capstone
cd mini_capstone
rake db:create
rails generate controller api/products  <-- all controller names must be plural
subl .
rails generate model Product name price:integer image_url description          

                        ^ Name of model upper camelcase and singular.
                          Attributes default to string if data type not specified
                                                                        
rake db:migrate                           
rails console   (or open seeds.rb and enter this data as one hash at a time followed by product.save -- remember to add {} around the hash--ex.: product = Product.new({all the hash data here})                                                                              
product = Product.new(name: "Dialogue", price: 40, image_url: "google.com/images.html", description: "a conversation for sale")

product.save

git add --all
git commit -m "added products to seed.rb"

git push origin master

Now open config->routes / config->controller / views

Rails.application.routes.draw do          <-- in the routes.rb file
  namespace :api do
    get '/all_products' => 'products#all_products'
    get '/one_product' => 'products#one_product'
  end
end


class Api::ProductsController < ApplicationController
  def all_products
    @products = Product.all
    render 'all_products.json.jbuilder'
  end
  
  def one_product
    @product = Product.first
    render 'one_product.json.jbuilder'
  end
end


json.array! @products.each do |product|           <-- in a file all_products.json.jbuilder
  json.id product.id
  json.name product.name  
  json.price product.price
  json.image_url product.image_url
  json.description product.description
end

json.id @product.id            <-- in file one_product.json.jbuilder
json.name @product.name
json.price @product.price
json.image_url @product.image_url
json.description @product.description

==============================================================================================

Falsey means evaluates as false.
Truthy means evaluates as true.

In Ruby, only nil or false are falsey.

!!(expression) is truthy if the expression is not false.

5   <-- evaluates as truthy
5 && 6  <-- evaluates as truthy and returns 6
"hello" && 5 && true <-- evaluates as truthy and returns true
5 && nil && "ghost" <-- evaluates as falsey and returns nil
false && "ghost" <-- evaluates as falsey and returns false

5 || 6 evaluates as truthy and returns 5
"hello" || 5 || false evaluates as truthy and returns "hello"

5 || 6 && "WAT"  evaluates as truthy and returns 5
"hello" && 5 || true evaluates as truthy and returns 5
false || "kazoo" && 17 evaluates as truthy and returns 17
nil && 77 || "ghost" evaluates as falsey and returns nil
(55 && "hi") || 9 evaluates as truthy and returns "hi"

(5||6) && ("WAT"||9) evaluates as truthy and returns "WAT"
("hello" && 0)||(5 && true) evaluates as truthy and returns 0
(false || "kazoo" && true) || 17 evaluates as truthy and returns true
nil && (true || true || true) evaluates as falsey and returns nil
(true && false) || (true && false) evaluates as falsey and returns false

!(5 || 6) && ("WAT" || 9) returns false and evaluates as falsey
("hello" && 0) || !(5 && true) returns 0 and evaluates as truthy
(false || "kazoo" && [3,4] && !!17 returns true and evaluates as truthy
!nil && !(true || false || true) returns false and evaluates as falsey

START->false||nil||true/[4,3]&&!5||FINISH

==================================================================================

string query parameters (params)    <-- http://www.google.com/search?q=dog      <-- google search for dog uses string query parameter with ?q=dog added to the URL
URL segment params  
body params (form params)

@message = params[:my_message] <-- is a hash that is given to you with rails in a web request that allows you access to the parameters

http://localhost:3000/api/query_params?my_message=yelp&message_2=welp&message_3=try again
^translates to
http://localhost:3000/api/query_params?my_message=yelp&message_2=welp&message_3=try%20again