Saner and cleaner actions with action_args

.rubocop.yml

@@ -13,3 +13,6 @@ Layout:
 
 Metrics:
   Enabled: false
+
+Naming/MethodParameterName:
+  Enabled: false

Gemfile

@@ -26,6 +26,8 @@ gem "stimulus-rails"
 
 gem 'tailwindcss-rails'
 
+gem 'action_args'
+
 gem 'active_decorator'
 
 # Use Redis adapter to run Action Cable in production

Gemfile.lock

@@ -1,6 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
+    action_args (2.7.3)
     actioncable (8.0.3)
       actionpack (= 8.0.3)
       activesupport (= 8.0.3)
@@ -349,6 +350,7 @@ PLATFORMS
   x86_64-linux-musl
 
 DEPENDENCIES
+  action_args
   active_decorator
   aws-sdk-s3 (~> 1)
   bootsnap

app/controllers/messages_controller.rb

@@ -1,16 +1,16 @@
 class MessagesController < ApplicationController
   PER_PAGE = 50
 
-  # GET /messages
-  def index
-    if (list_name = params[:list_name])
+  # GET /ruby-dev or /q=searchterm
+  def index(list_name: nil, q: nil, page: nil)
+    if list_name
       @list = List.find_by_name list_name
 
       messages = Message.with_recursive(parent_and_children: [Message.where(list_id: @list, parent_id: nil).order(:id).limit(100), Message.joins('inner join parent_and_children on messages.parent_id = parent_and_children.id')])
         .joins('inner join parent_and_children on parent_and_children.id = messages.id')
       @messages = compose_tree(messages)
-    elsif (query = params[:q])
-      search query
+    elsif q
+      search q, page
 
       render :search
     else
@@ -20,10 +20,10 @@ def index
     end
   end
 
-  # GET /messages/ruby-dev/1
-  def show
-    @list = List.find_by_name(params[:list_name])
-    @message = Message.find_by(list_id: @list, list_seq: params[:list_seq])
+  # GET /ruby-dev/1
+  def show(list_name:, list_seq:)
+    @list = List.find_by_name(list_name)
+    @message = Message.find_by!(list_id: @list, list_seq: list_seq)
   end
 
   private
@@ -38,8 +38,7 @@ def get_list_ids(params)
     list_ids
   end
 
-  def search(query)
-    page = params[:page].to_i
+  def search(query, page)
     list_ids = get_list_ids(params)
     if list_ids.empty?
       raise "Need to select at least one list"
@@ -48,7 +47,7 @@ def search(query)
     # %> and <-> are defined by pg_trgm.
     # https://www.postgresql.org/docs/17/pgtrgm.html
     message_where = Message.where('body %> ? AND list_id IN (?)', query, list_ids).order(Arel.sql('body <-> ?', query))
-    @messages = message_where.offset(page * PER_PAGE).limit(PER_PAGE)
+    @messages = message_where.offset(page.to_i * PER_PAGE).limit(PER_PAGE)
   end
 
   def compose_tree(messages)