How to get the ID in ruby on rails on windows

Question

I am currently doing simple CRUD. I already done in part of adding a new item, display all the items and now I want to view the specific item..

Question: How can I do that? Is my syntax correct?

Note: If yes, I am encountered erro " undefined local variable or method `item_showItem_path' for #<#:0xaf75068> Did you mean? items_addItem_path "

View

<h1>Welcome to my First CRUD!</h1>
    <table border = "1" width="100%">
        <tr>
            <td>ID</td>
            <td>Name</td>
            <td>Description</td>
            <td>Price</td>
            <td>Created At</td>
            <td>Updated At</td>
            <td>Action</td>
        </tr>
        <% @items.each do |t| %>

        <tr>
            <td><%= t.id %></td>
            <td><%= t.name %></td>
            <td><%= t.description %></td>
            <td><%= t.price %></td>
            <td><%= t.created_at.strftime("%B, %d, %Y") %></td>
            <td><%= t.updated_at %></td>
            <td><%= link_to 'View ITEM', item_showItem_path%></td> 
        </tr>
        <% end %>

    </table>
<%= link_to 'Add ITEM', items_addItem_path %>

Controller

class ItemsController < ApplicationController
    before_action :set_item, only: [:show,:edit,:destroy] 
    def index

        @items = Item.all.order('created_at DESC')
    end
    def addItem

    end
    def create
      @post = Item.new(post_params)
      @post.save
      redirect_to @items_path
    end
    def showItem
        @post = Item.find(params[:id])
    end
    def show

    end
    private
        def post_params
            params.require(:item).permit(:name, :description, :price)
        end
        def set_post
            @post = Item.find(params[:id])
        end
end

My show view

<h1 class="name">
    <%= @post.name%>
</h1>
<h1 class="description">
    <%= @post.description%>
</h1><h1 class="date">
    Submitted <%= time_ago_in_words(@post.created_at)%> Ago
</h1>

<%= link_to 'BACK', items_path %>

Routes

Rails.application.routes.draw do
    root "items#index"
            # URL           Controller#method
    get '/items/addItem' => 'items#addItem'
    get '/items/' => 'items#index'
    post '/items/create' => 'items#create'
    get '/items/showItem/:id' => 'items#showItem'


end

Answer 1

Part of learning Rails is learning how to use the conventions to your advantage - at which you're failing since you're setup is more complex than it needs to be.

To create CRUD routes for a resource use resources

Rails.application.routes.draw do
  root to: "items#index"
  resources :items
end

This will create the following RESTful routes:

   Prefix Verb   URI Pattern               Controller#Action
    items GET    /items(.:format)          items#index
          POST   /items(.:format)          items#create
 new_item GET    /items/new(.:format)      items#new
edit_item GET    /items/:id/edit(.:format) items#edit
     item GET    /items/:id(.:format)      items#show
          PATCH  /items/:id(.:format)      items#update
          PUT    /items/:id(.:format)      items#update
          DELETE /items/:id(.:format)      items#destroy

Which means that we can create a link to item by:

<%= link_to item.name, item_path(item) %>
# Or 
<%= link_to item.name, item %>

It also lets you do the rest of the CRUD operations on a item by changing the request method while the path remains the same:

<%= button_to 'Delete item', item_path(@item), method: :delete %>

# This is explicit just for the sake of the example
# normally you would just use `form_for(@item)`
<%= form_for(@item, path: item_path(@item), method: :patch) do |f| %>
  <h1>Edit item</h1>
  # ...
<% end %>

Note that there is no special path for create either. You create a new record by sending a POST request to the collection path ( /items ).

This is what the simplest possible conventional CRUD controller for a classic web looks like:

class ItemsController < ApplicationController
  before_action :set_item, only: [:show,:edit,:destroy] 

  # GET /items/new
  def new
    @item = Item.new
  end

  # POST /items
  def create
    @item = Item.new(post_params)
    if @item.save
      redirect_to @item, success: 'Item created'
    else
      render :new, error: 'Item was not valid'
    end
  end

  # GET /items
  def index
    @items = Item.all.order('created_at DESC')
  end

  # GET /items/:id
  # We don't even need to declare this since 
  # Rails will render the (items/show) view by convention.
  # 
  # def show
  # end

  # GET /items/:id/edit
  # We don't even need to declare this since 
  # Rails will render the (items/edit) view by convention.
  # 
  # def edit
  # end

  # PUT|PATCH /items/:id
  def update
    if @item.update(item_params)
      redirect_to @item, success: 'Item updated.'
    else
      render :edit
    end
  end

  # DELETE /items/:id
  def destroy
    @item.destroy
    redirect_to items_path, success: 'Item deleted.'
  end

  private
  def item_params
    params.require(:item).permit(:name, :description, :price)
  end
  def set_item
    @item = Item.find(params[:id])
  end
end

Answer 2

you will need to pass item id in your item_showItem_path

change this

<td><%= link_to 'View ITEM', item_showItem_path%></td>

to this

<td><%= link_to 'View ITEM', item_showItem_path(t) %></td>

or

<td><%= link_to 'View ITEM', item_showItem_path(t.id) %></td>

you can see in your routes, it is expecting :id

get '/items/showItem/:id' => 'items#showItem' . Once you pass the object t , rails will get id from that object.

SIDE NOTE:

your naming convention is not following ruby convention. normally in ruby we name methods using underscore.

eg showItem will be show_item

I would also rename variable t to item so it is easier to understand.

You already have show method in controller, so there is no need to define new method and route for showItem. you can just use show method.

You can also rename addItem to def new if you want to follow Rails convention.