Vfrdtyky

In my app I can search consumptions by dates

I have an active record model Consumption which belongs_to :users and a model ConsumptionSearch

consumption.rb

class Consumption < ApplicationRecord

    belongs_to :user

end

consumption_search.rb

class ConsumptionSearch 

    attr_reader :date_from, :date_to



    def initialize(params)

        params ||= {}

        @date_from = parsed_date(params[:date_from],Time.now.beginning_of_month.to_date.to_s)

        @date_to   = parsed_date(params[:date_to], (Date.today + 1).to_s)

    end



    def date_range

        Consumption.where('created_at BETWEEN ? AND ?', @date_from, @date_to)

    end



    private

        def parsed_date(date_string, default)

            Date.parse(date_string)

            rescue ArgumentError, TypeError

            default

        end

end

In the consumptions_controller in the index action I can retrieve the wanted consumptions by date

class ConsumptionsController < ApplicationController

    def index

        @search = ConsumptionSearch.new(params[:search])

        @consumptions = @search.date_range

        @consumptions = @consumptions.order('created_at ASC').where(user_id: current_user.id)

    end

end

consumptions schema may help:

  create_table "consumptions", force: :cascade do |t|

    t.float "total_price"

    t.float "kilometers"

    t.string "shop"

    t.float "liter_price"

    t.float "total_liters"

    t.datetime "created_at", null: false

    t.datetime "updated_at", null: false

    t.integer "user_id"

    t.float "difference", default: 0.0

  end

So in my consumptions/view/index.html.erb I just have to iterrate over @consumptions to display what I need.

The question is:

How can I make it more "ruby way", I have too much logic in the view... Where and how should I extract the logic? thx

<%= price = (@consumptions.map { |c| c.total_price }.sum - @consumptions.last.total_price).round(2) %> 

<%= total_km = (@consumptions.map { |c| c.difference }.sum).round.abs %>

<%= (price / total_km).round(4) %> 

<%= (price / total_km * 100).round(2) %>

You can create helper: app/helpers/consumptions_helper.rb

module ConsumptionsHelper

 def some_logic

   ...

 end

end

and use it in the view

<%= some_logic %>

Please check RoR doc here
https://api.rubyonrails.org/classes/ActionController/Helpers.html

Why not add the logic to your ConsumptionSearch class? You are already abstracting logic to it. And, you are already accessing it in the view. So, perhaps something like:

class ConsumptionSearch 

  attr_reader :date_from, :date_to



    def initialize(params)

      params ||= {}

      @date_from = parsed_date(params[:date_from],Time.now.beginning_of_month.to_date.to_s)

      @date_to   = parsed_date(params[:date_to], (Date.today + 1).to_s)

    end



    def date_range

      Consumption.where('created_at BETWEEN ? AND ?', @date_from, @date_to)

    end



    def price

      ...

    end



    def total_km

      ...

    end



    def price_per_km(round_to)

      (price/total_km).round(round_to)

    end



  private



    def parsed_date(date_string, default)

      Date.parse(date_string)

      rescue ArgumentError, TypeError

      default

    end

end

And then in view:

<%= @consumptions.price %> 

<%= @consumptions.total_km %>

<%= @consumptions.price_per_km(4) %> 

<%= @consumptions.price_per_km(2) %>

Personally, helpers are not my favorite thing. But, I realize that some people use them regularly and with great success. I'm just odd that way.