Presentation Logic

CodecoreBoot11.md

draper gem

gem 'draper' in your gemfile

bundle

You generate a decorator for a specific object

bin/rails g decorator Campaign

In your config/application.rb We need to add this line so that rails will load the decorator files. By default rails will only load associated files.

config_autoload_paths << RAils.root.join("app","decorators")

app/decorators is where all your decorator files will be stored.

delegate_all

This line of code lets all the methods to be used in decor

Add

def name
  @object.name.titleize
end

We add decorate to the controller file

campaigns/controller

def find_campaign
  @campaign = Campaign.friendly.find(params[:id]).decorate
end

We shoud remove titleize from the view files

app/views/show.html.erb

<%[email protected] %>
to
<%[email protected] %>

In your decorator h is a helper method

def goal
  h.number_to_currency object.goal
end

Formatting the end date

def end_date
  h.formatted_date_time object.end_date
end

<%= @campaign.state_label%>

def state_label
  h.content_tag :div, class: "label label-default" do
    object.aasm_state
  end
end

If you want to change the class

def state_label
  bootstrap_classes = {"draft" => "label-default",
                        "unfunded" => "label-danger",
                        "published" => "label-success",
                        "canceled" => "label-warning"}
  h.content_tag :div, class: "label #{bootstrap_classes[object.aasm_state]}" do
    object.aasm_state
  end
end

<% if @campaign.draft? %>
  <%= link_to "Publish", campaign_publishings_path(@campaign),
                         method: :post,
                         class: "btn btn-primary",
                        data: {confirm: "Are you sure? You won't be able to edit the campaign after it's published."} %>
<% end %>
#Turning this into
<%= @campaign.publish_button %>

def publish_button
  if object.draft?
   h.link_to "Publish", h.campaign_publishings_path(object),
                         method: :post,
                         class: "btn btn-primary",
                         data: {confirm: "Are you sure? You won't be able to edit the campaign after it's published."}
  end
end

---

Service Objects There isn't a standard way to use service object so we will create from scratch 1. Add new folder services ex. app/services Add new folder campaigns app/services/campaign Add new file publish_campaign.rb app/services/campaign/publish_campaign.rb 2. gem 'Virtus' 3.

config_autoload_paths << RAils.root.join("app","services")

class Campaigns::PublishCampaign

  include Virtus.model
  
  attribute :campaign, Campaign
  
  def call
    if campaign.publish!
      DetermineCampaignStateJob.set(wait_until: campaign.end_date).perform_later(campaign)
      true
    else
      false
    end
  end

end