perf: EventCardComponent + Solid Cache for event listings

Gemfile

@@ -129,3 +129,5 @@ gem 'scout_apm'
 
 gem 'carrierwave-aws', '~> 1.6'
 gem 'sitemap_generator', '~> 7.0'
+
+gem "solid_cache", "~> 1.0"

Gemfile.lock

@@ -555,6 +555,10 @@ GEM
     snaky_hash (2.0.6)
       hashie (>= 0.1.0, < 6)
       version_gem (>= 1.1.8, < 3)
+    solid_cache (1.0.10)
+      activejob (>= 7.2)
+      activerecord (>= 7.2)
+      railties (>= 7.2)
     sprockets (4.2.2)
       concurrent-ruby (~> 1.0)
       logger
@@ -698,6 +702,7 @@ DEPENDENCIES
   simplecov
   simplecov-lcov
   sitemap_generator (~> 7.0)
+  solid_cache (~> 1.0)
   sprockets-rails
   stimulus-rails
   stripe
@@ -918,6 +923,7 @@ CHECKSUMS
   sitemap_generator (7.0.2) sha256=c5c15f265edc4bb0eb3954c80a62f3f33576cf8b6e3af72e90f030613822134d
   slop (3.6.0) sha256=76ccab03be66bfcab4838cdc07cab019cd3e192a3538266246749e79e4788803
   snaky_hash (2.0.6) sha256=3663cae48cdef582b517025cf8a39d8789996eaf0b4ed89e2f0624836505654a
+  solid_cache (1.0.10) sha256=bc05a2fb3ac78a6f43cbb5946679cf9db67dd30d22939ededc385cb93e120d41
   sprockets (4.2.2) sha256=761e5a49f1c288704763f73139763564c845a8f856d52fba013458f8af1b59b1
   sprockets-rails (3.5.2) sha256=a9e88e6ce9f8c912d349aa5401509165ec42326baf9e942a85de4b76dbc4119e
   ssrf_filter (1.5.0) sha256=e03dcdb9d1730d7f6710532a606b3543df2a448a0293ce04a2d995523c5a97f6

app/components/event_card_component.html.erb

@@ -0,0 +1,75 @@
+<% cache @event.cache_key_with_version do %>
+  <div class="card mb-4" data-test="event">
+    <div class="card-body">
+      <div class="d-md-flex justify-content-md-between">
+        <div class="order-md-2">
+          <% if @event.chapter %>
+            <span class="badge bg-primary mb-3 mb-md-0">
+              <%= link_to @event.chapter.name, @event.chapter.slug, class: "text-light text-decoration-none" %>
+            </span>
+          <% end %>
+          <% if user_presenter %>
+            <% if user_presenter.attending?(@event) %>
+              <span class="badge bg-success mb-3 mb-md-0">
+                <%= link_to "Attending", @event.path, class: "text-light text-decoration-none" %>
+              </span>
+            <% end %>
+            <% if user_presenter.organiser? && user_presenter.event_organiser?(@event) %>
+              <span class="badge bg-secondary mb-3 mb-md-0">
+                <%= link_to "Manage", @event.admin_path, class: "text-light text-decoration-none" %>
+              </span>
+            <% end %>
+          <% end %>
+        </div>
+        <div class="order-md-1">
+          <h3 class="h5">
+            <%= link_to @event.to_s, @event.path %>
+            <% if @event.venue.present? %>
+              at
+              <%= link_to @event.venue.name, @event.venue.website %>
+            <% end %>
+          </h3>
+        </div>
+      </div>
+
+      <div class="mt-3">
+        <p class="mb-0">
+          <i class="far fa-calendar"></i>
+          <%= @event.date %>
+        </p>
+        <p>
+          <i class="far fa-clock"></i>
+          <%= @event.time %>
+        </p>
+      </div>
+
+        <div class="d-md-flex justify-content-md-between align-items-md-center">
+          <% if @event.organisers.any? %>
+            <div class="mb-3 mb-md-0">
+              <% @event.organisers.each do |organiser| %>
+                <%= image_tag(organiser.avatar(26), class: "rounded-circle", title: organiser.full_name, alt: organiser.full_name) %>
+              <% end %>
+            </div>
+          <% end %>
+
+          <% if @event.sponsors.any? %>
+            <div class="ms-auto">
+              <% @event.sponsors.each do |sponsor| %>
+                <%= link_to sponsor.website, class: "d-inline-block" do %>
+                  <%= image_tag(sponsor.avatar.thumb.url, class: "sponsor-sm mx-1", alt: sponsor.name) %>
+                <% end %>
+              <% end %>
+            </div>
+          <% end %>
+
+          <% if @event.is_a?(MeetingPresenter) && @event.venue.present? %>
+            <div class="ms-auto">
+              <%= link_to @event.venue.website, class: "d-inline-block" do %>
+                <%= image_tag(@event.venue.avatar.url, class: "sponsor-sm", alt: @event.venue.name) %>
+              <% end %>
+            </div>
+          <% end %>
+        </div>
+    </div>
+  </div>
+<% end %>

app/components/event_card_component.rb

@@ -0,0 +1,11 @@
+class EventCardComponent < ViewComponent::Base
+  def initialize(event_card:, user: nil)
+    @event = event_card
+    @user = user
+  end
+
+  # Wraps raw Member in MemberPresenter; double-wrapping a presenter is a no-op.
+  def user_presenter
+    @user && MemberPresenter.new(@user)
+  end
+end

app/views/chapter/show.html.haml

@@ -29,13 +29,13 @@
           %h2.mb-4= t('homepage.events.upcoming')
           - @upcoming_workshops.each do |date, workshops|
             %h3.h5= date
-            = render workshops
+            = render EventCardComponent.with_collection(workshops)
 
         - if @latest_workshops.any?
           .pt-4
             %h2.mb-4 Past Events
             - @latest_workshops.each do |date, workshops|
-              = render workshops
+              = render EventCardComponent.with_collection(workshops)
 
 - if @recent_sponsors.any?
   .py-4.py-lg-5.bg-light

app/views/dashboard/dashboard.html.haml

@@ -32,4 +32,4 @@
           There are no upcoming events announced for the chapters you are subscribed to.
         - @ordered_events.each do |date, workshops|
           %h4= date
-          = render workshops
+          = render EventCardComponent.with_collection(workshops, user: current_user)

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 EventCardComponent.with_collection(workshops, user: current_user)
 
         - if @has_more_events
           = link_to 'Explore all events →', upcoming_events_path, class: 'btn btn-outline-primary mt-3'

app/views/events/_events.html.haml

@@ -1,7 +1,7 @@
-- grouped_events.each do |date, workshops|
+- grouped_events.each do |date, events|
   .row
     .col-12
       %h3.h5= date
   .row
     .col-md-8
-      = render workshops
+      = render EventCardComponent.with_collection(events)

config/cache.yml

@@ -0,0 +1,17 @@
+development:
+  store_options:
+    max_age: <%= 60.days.to_i %>
+    max_size: <%= 256.megabytes %>
+    namespace: <%= Rails.env %>
+
+test:
+  store_options:
+    max_age: <%= 60.days.to_i %>
+    max_size: <%= 256.megabytes %>
+    namespace: <%= Rails.env %>
+
+production:
+  store_options:
+    max_age: <%= 60.days.to_i %>
+    max_size: <%= 500.megabytes %>
+    namespace: <%= Rails.env %>

config/environments/production.rb

@@ -52,7 +52,7 @@
   config.active_support.report_deprecations = false
 
   # Replace the default in-process memory cache store with a durable alternative.
-  # config.cache_store = :mem_cache_store
+  config.cache_store = :solid_cache_store
 
   # Replace the default in-process and non-durable queuing backend for Active Job.
   # config.active_job.queue_adapter = :resque

db/cache_schema.rb

@@ -0,0 +1,12 @@
+ActiveRecord::Schema[7.2].define(version: 1) do
+  create_table "solid_cache_entries", force: :cascade do |t|
+    t.binary "key", limit: 1024, null: false
+    t.binary "value", limit: 536870912, null: false
+    t.datetime "created_at", null: false
+    t.integer "key_hash", limit: 8, null: false
+    t.integer "byte_size", limit: 4, null: false
+    t.index ["byte_size"], name: "index_solid_cache_entries_on_byte_size"
+    t.index ["key_hash", "byte_size"], name: "index_solid_cache_entries_on_key_hash_and_byte_size"
+    t.index ["key_hash"], name: "index_solid_cache_entries_on_key_hash", unique: true
+  end
+end

db/migrate/20260702102700_create_solid_cache_entries.rb

@@ -0,0 +1,14 @@
+class CreateSolidCacheEntries < ActiveRecord::Migration[8.1]
+  def change
+    create_table "solid_cache_entries", force: :cascade do |t|
+      t.binary "key", limit: 1024, null: false
+      t.binary "value", limit: 536870912, null: false
+      t.datetime "created_at", null: false
+      t.integer "key_hash", limit: 8, null: false
+      t.integer "byte_size", limit: 4, null: false
+      t.index ["byte_size"], name: "index_solid_cache_entries_on_byte_size"
+      t.index ["key_hash", "byte_size"], name: "index_solid_cache_entries_on_key_hash_and_byte_size"
+      t.index ["key_hash"], name: "index_solid_cache_entries_on_key_hash", unique: true
+    end
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[8.1].define(version: 2026_06_21_050948) do
+ActiveRecord::Schema[8.1].define(version: 2026_07_02_102700) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "pg_catalog.plpgsql"
 
@@ -483,6 +483,17 @@
     t.datetime "updated_at", precision: nil
   end
 
+  create_table "solid_cache_entries", force: :cascade do |t|
+    t.integer "byte_size", null: false
+    t.datetime "created_at", null: false
+    t.binary "key", null: false
+    t.bigint "key_hash", null: false
+    t.binary "value", null: false
+    t.index ["byte_size"], name: "index_solid_cache_entries_on_byte_size"
+    t.index ["key_hash", "byte_size"], name: "index_solid_cache_entries_on_key_hash_and_byte_size"
+    t.index ["key_hash"], name: "index_solid_cache_entries_on_key_hash", unique: true
+  end
+
   create_table "sponsors", id: :serial, force: :cascade do |t|
     t.text "accessibility_info"
     t.string "avatar"

script/benchmark_events.rb

@@ -0,0 +1,33 @@
+#!/usr/bin/env ruby
+# Run: DB_NAME=codebar_dump bundle exec ruby script/benchmark_events.rb
+ENV["RAILS_ENV"] ||= "development"
+require_relative "../config/environment"
+require "benchmark"
+
+session = ActionDispatch::Integration::Session.new(Rails.application)
+session.host = "localhost"
+
+def measure(session, path)
+  qc = 0
+  cb = ->(*, **) { qc += 1 }
+  time = nil
+  ActiveSupport::Notifications.subscribed(cb, "sql.active_record") do
+    time = Benchmark.measure { session.get(path) }
+  end
+  [time.real, qc]
+end
+
+puts "=== Database: #{ActiveRecord::Base.connection_db_config.database} ===\n\n"
+
+%w[/events/upcoming /events/past /events/past?page=2].each do |path|
+  ActiveRecord::Base.connection.query_cache.clear
+  Rails.cache.clear if Rails.cache
+
+  cold_t, cold_q = measure(session, path)
+  warm = 3.times.map { measure(session, path).first }
+
+  puts "#{path}"
+  puts "  cold: #{cold_t.round(3)}s | #{cold_q} queries"
+  puts "  warm: #{warm.sort[1].round(3)}s (min #{warm.min.round(3)}, max #{warm.max.round(3)})"
+  puts
+end