Generate the ids for the workshops a member is attending in one go

This removes a call to '#attending?' for every workshop, instead creating a single method to generate the list.

Running locally with a small sample, it reduced loading time for the homepage by 70%

Signed-off-by: jonathan.kerr <3410350+jonodrew@users.noreply.github.com>

Author: jonodrew

app/controllers/dashboard_controller.rb

@@ -4,7 +4,7 @@ class DashboardController < ApplicationController
 
   DEFAULT_UPCOMING_EVENTS = 5
 
-  helper_method :year_param
+  helper_method :year_param, :attending_workshops
 
   def show
     @chapters = Chapter.active.all.order(:created_at)
@@ -13,7 +13,7 @@ def show
       hash[key] = EventPresenter.decorate_collection(value)
       hash
     end
-
+    @attending_ids = attending_workshops
     @testimonials = Testimonial.order(Arel.sql('RANDOM()')).limit(5).includes(:member)
   end
 
@@ -84,4 +84,8 @@ def all_events(workshops)
 
     [*workshops, *events, meeting].uniq.compact
   end
+
+  def attending_workshops
+    current_user.nil? ? Set.new : current_user.workshop_invitations.accepted.pluck(:id).to_set
+  end
 end

app/views/dashboard/show.html.haml

@@ -71,7 +71,7 @@
         %h2.h3.mb-4= t('homepage.events.upcoming')
         - @upcoming_workshops.each do |date, workshops|
           %h3.h5= date
-          = render workshops
+          = render workshops, attending_ids: @attending_ids
 
     .col-lg-4.pl-lg-5
       %h3

app/views/events/_event.html.haml

@@ -5,10 +5,11 @@
         - if event.chapter
           %span.badge.bg-primary.mb-3.mb-md-0
             = link_to event.chapter.name, event.chapter.slug, class: 'text-light text-decoration-none' 
-        - if @user
-          - if @user.attending?(event.__getobj__)
+        - if !attending_ids.blank?
+          - if attending_ids.include?(event.id)
             %span.badge.bg-success.mb-3.mb-md-0
               = link_to 'Attending', event.path, class: 'text-light text-decoration-none'
+        - if @user
           - if @user.event_organiser?(event)
             %span.badge.bg-secondary.mb-3.mb-md-0
               = link_to 'Manage', event.admin_path, class: 'text-light text-decoration-none'

app/views/workshops/_workshop.html.haml

@@ -1 +1 @@
-= render partial: 'events/event', locals: { event: workshop }
+= render partial: 'events/event', locals: { event: workshop, attending_ids: attending_ids }