Install solid cable using the primary database

Gemfile

@@ -8,4 +8,5 @@ gem "activestorage"
 gem "rake"
 gem "rspec"
 gem "rubocop-katalyst"
+gem "solid_cable"
 gem "solid_queue"

Gemfile.lock

@@ -8,6 +8,12 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
+    actioncable (8.1.3)
+      actionpack (= 8.1.3)
+      activesupport (= 8.1.3)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+      zeitwerk (~> 2.6)
     actionpack (8.1.3)
       actionview (= 8.1.3)
       activesupport (= 8.1.3)
@@ -90,6 +96,7 @@ GEM
     minitest (6.0.6)
       drb (~> 2.0)
       prism (~> 1.5)
+    nio4r (2.7.5)
     nokogiri (1.19.4-aarch64-linux-gnu)
       racc (~> 1.4)
     nokogiri (1.19.4-aarch64-linux-musl)
@@ -218,6 +225,11 @@ GEM
       rubocop-rspec (~> 3.5)
     ruby-progressbar (1.13.0)
     securerandom (0.4.1)
+    solid_cable (4.0.0)
+      actioncable (>= 7.2)
+      activejob (>= 7.2)
+      activerecord (>= 7.2)
+      railties (>= 7.2)
     solid_queue (1.4.0)
       activejob (>= 7.1)
       activerecord (>= 7.1)
@@ -236,6 +248,10 @@ GEM
     unicode-emoji (4.2.0)
     uri (1.1.1)
     useragent (0.16.11)
+    websocket-driver (0.8.1)
+      base64
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.5)
     zeitwerk (2.8.2)
 
 PLATFORMS
@@ -254,9 +270,11 @@ DEPENDENCIES
   rake
   rspec
   rubocop-katalyst
+  solid_cable
   solid_queue
 
 CHECKSUMS
+  actioncable (8.1.3) sha256=e5bc7f75e44e6a22de29c4f43176927c3a9ce4824464b74ed18d8226e75a80f0
   actionpack (8.1.3) sha256=af998cae4d47c5d581a2cc363b5c77eb718b7c4b45748d81b1887b25621c29a3
   actionview (8.1.3) sha256=1347c88c7f3edb38100c5ce0e9fb5e62d7755f3edc1b61cce2eb0b2c6ea2fd5d
   activejob (8.1.3) sha256=a149b1766aa8204c3c3da7309e4becd40fcd5529c348cffbf6c9b16b565fe8d3
@@ -291,6 +309,7 @@ CHECKSUMS
   loofah (2.25.1) sha256=d436c73dbd0c1147b16c4a41db097942d217303e1f7728704b37e4df9f6d2e04
   marcel (1.2.1) sha256=1678e9360e32f9eafa917c80029e2f6d10b2715c66a4b87b6d0da9b9cd1f859f
   minitest (6.0.6) sha256=153ea36d1d987a62942382b61075745042a2b3123b1cd48f4c3675af9cc7d6f1
+  nio4r (2.7.5) sha256=6c90168e48fb5f8e768419c93abb94ba2b892a1d0602cb06eef16d8b7df1dca1
   nokogiri (1.19.4-aarch64-linux-gnu) sha256=1269fb644a6de405057a53dd5c762b1209b43ca7424f839454d3dbc677c31a8f
   nokogiri (1.19.4-aarch64-linux-musl) sha256=35c65b9ce72b3bb03207bdbe7067915019dc18c1b9b59139684bd6690fdd01af
   nokogiri (1.19.4-arm-linux-gnu) sha256=a301313e38bb065d68239e79734bcd6f56fb6efaacebde29e9abf2a4735340ca
@@ -336,6 +355,7 @@ CHECKSUMS
   rubocop-rspec_rails (2.32.0) sha256=4a0d641c72f6ebb957534f539d9d0a62c47abd8ce0d0aeee1ef4701e892a9100
   ruby-progressbar (1.13.0) sha256=80fc9c47a9b640d6834e0dc7b3c94c9df37f08cb072b7761e4a71e22cff29b33
   securerandom (0.4.1) sha256=cc5193d414a4341b6e225f0cb4446aceca8e50d5e1888743fac16987638ea0b1
+  solid_cable (4.0.0) sha256=8379680ef6bf36e195eb876a6306ea290f87d5fa10bc4a757bc2a918f83229b5
   solid_queue (1.4.0) sha256=e6a18d196f0b27cb6e3c77c5b31258b05fb634f8ed64fb1866ed164047216c2a
   stringio (3.2.0) sha256=c37cb2e58b4ffbd33fe5cd948c05934af997b36e0b6ca6fdf43afa234cf222e1
   thor (1.5.0) sha256=e3a9e55fe857e44859ce104a84675ab6e8cd59c650a49106a05f55f136425e73
@@ -346,6 +366,8 @@ CHECKSUMS
   unicode-emoji (4.2.0) sha256=519e69150f75652e40bf736106cfbc8f0f73aa3fb6a65afe62fefa7f80b0f80f
   uri (1.1.1) sha256=379fa58d27ffb1387eaada68c749d1426738bd0f654d812fcc07e7568f5c57c6
   useragent (0.16.11) sha256=700e6413ad4bb954bb63547fa098dddf7b0ebe75b40cc6f93b8d54255b173844
+  websocket-driver (0.8.1) sha256=5ab238238ce230e5d4b262d2be39624c867914eab99171dc4952b58b577c2d96
+  websocket-extensions (0.1.5) sha256=1c6ba63092cda343eb53fc657110c71c754c56484aad42578495227d717a8241
   zeitwerk (2.8.2) sha256=7212a61311083c604184b1ea2574b9aa05cd14f855a0841c06985cabe9181d12
 
 BUNDLED WITH

lib/generators/thermite/install/solid_cable/USAGE

@@ -0,0 +1,16 @@
+Description:
+    Installs Solid Cable using a single, shared database (Katalyst's preferred setup).
+
+    Unlike `solid_cable:install`, this does not provision a separate cable
+    database. The solid_cable tables are added to the primary database via a
+    normal migration in db/migrate, and config/cable.yml uses the solid_cable
+    adapter without a `connects_to` configuration.
+
+    Requires the solid_cable gem to be present in the host application.
+
+Example:
+    bin/rails thermite:install:solid_cable
+
+    This will:
+        Create config/cable.yml
+        Create a db/migrate migration for the solid_cable tables

lib/generators/thermite/install/solid_cable/solid_cable_generator.rb

@@ -0,0 +1,98 @@
+# frozen_string_literal: true
+
+require "rails"
+require "rails/generators"
+require "rails/generators/active_record/migration"
+
+require "active_record"
+require "yaml"
+
+# For a single-database install, solid cable's documented setup is to copy the contents
+# of db/cable_schema.rb into a normal migration, delete db/cable_schema.rb,
+# remove connects_to from config/cable.yml, then run db:migrate.
+# Thermite follows that path by generating the migration directly.
+#
+# solid_cable is an optional dependency: it is required lazily in #verify_solid_cable!
+# so the generator still loads (and lists) when solid_cable is absent.
+module Thermite
+  module Install
+    class SolidCableGenerator < Rails::Generators::Base
+      # Provides migration_template, next_migration_number (timestamped) and the
+      # CreateMigration action that makes re-runs safe: identical content is
+      # skipped, a same-named migration with different content raises a conflict.
+      include ActiveRecord::Generators::Migration
+
+      # Reuse solid_cable's own templates. Resolved lazily so the class loads
+      # without solid_cable present; populated once #verify_solid_cable! requires it.
+      def self.source_root
+        ::SolidCable::InstallGenerator.source_root if defined?(::SolidCable::InstallGenerator)
+      end
+
+      # Search our own templates (the migration) first, then solid_cable's
+      # (cable.yml).
+      def self.source_paths
+        [File.expand_path("templates", __dir__), source_root].compact
+      end
+
+      # Our source_root points into solid_cable, so the inherited USAGE lookup
+      # would resolve to solid_cable's USAGE. Point it at ours instead.
+      def self.usage_path
+        File.expand_path("USAGE", __dir__)
+      end
+
+      # Fail early with a helpful message when solid_cable isn't available.
+      def verify_solid_cable!
+        require "solid_cable/version"
+        require "generators/solid_cable/install/install_generator"
+      rescue LoadError
+        raise Thor::Error, <<~MSG.strip
+          thermite:install:solid_cable requires the solid_cable gem, which is not available.
+          Add it to your Gemfile and run `bundle install`:
+
+              gem "solid_cable"
+        MSG
+      end
+
+      # Based on SolidCable::InstallGenerator#copy_files but writing schema to a migration instead
+      # @see https://github.com/rails/solid_cable#single-database-configuration
+      def copy_files
+        template "config/cable.yml"
+        migration_template "add_solid_cable.rb", "db/migrate/add_solid_cable.rb", skip: true
+      end
+
+      private
+
+      # The application's extra environments, derived from config/environments/*.rb so
+      # we don't hard-code names like "staging" / "uat".
+      def extra_environments
+        environments
+          .reject { |pathname| local?(pathname) || production?(pathname) }
+          .map { |path| path.basename(".rb").to_s }
+      end
+
+      def environments
+        Pathname(destination_root).join("config/environments").glob("*.rb")
+      end
+
+      def local?(pathname)
+        %w[development test].include?(pathname.basename(".rb").to_s)
+      end
+
+      def production?(pathname)
+        pathname.basename(".rb").to_s == "production"
+      end
+
+      def solid_cable_schema_body
+        schema = File.read(File.join(self.class.source_root, "db/cable_schema.rb"))
+
+        schema
+          # Keep only the schema block body.
+          .sub(%r{\A.*ActiveRecord::Schema[^\n]+do\n}, "")
+          .sub(/\nend\n?\z/, "")
+          .lines
+          .map { |line| line == "\n" ? line : "  #{line}" }
+          .join
+      end
+    end
+  end
+end

lib/generators/thermite/install/solid_cable/templates/add_solid_cable.rb.tt

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class <%= migration_class_name %> < ActiveRecord::Migration[<%= ActiveRecord::Migration.current_version %>]
+  def change
+<%= solid_cable_schema_body.chomp %>
+  end
+end

lib/generators/thermite/install/solid_cable/templates/config/cable.yml.tt

@@ -0,0 +1,16 @@
+development:
+  adapter: async
+
+test:
+  adapter: test
+
+production: &production
+  adapter: solid_cable
+  polling_interval: 0.1.seconds
+  message_retention: 1.day
+
+<% extra_environments.each do |environment| -%>
+
+<%= environment %>:
+  <<: *production
+<% end -%>

lib/thermite/tasks.rb

@@ -11,5 +11,10 @@
     task :active_storage do
       Rails::Command.invoke :generate, ["thermite:install:active_storage"]
     end
+
+    desc "Install Solid Cable"
+    task :solid_cable do
+      Rails::Command.invoke :generate, ["thermite:install:solid_cable"]
+    end
   end
 end

spec/generators/thermite/install/solid_cable_generator_spec.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+require "generators/thermite/install/solid_cable/solid_cable_generator"
+
+RSpec.describe Thermite::Install::SolidCableGenerator do
+  it "completes successfully" do
+    expect { run_generator }.not_to raise_error
+  end
+
+  it "writes cable config and migration" do
+    run_generator
+
+    assert_file "config/cable.yml"
+    assert_migration "db/migrate/add_solid_cable.rb"
+  end
+
+  it "includes non-standard environments like staging in the cable config" do
+    run_generator
+
+    assert_file "config/cable.yml", /^staging:/
+  end
+
+  it "raises a helpful error when solid_cable is unavailable" do
+    allow(generator).to receive(:require).and_raise(LoadError)
+
+    expect { generator.verify_solid_cable! }
+      .to raise_error(Thor::Error, /requires the solid_cable gem/)
+  end
+end

spec/support/generator_helpers.rb

@@ -2,6 +2,7 @@
 
 require "rails/generators/testing/behavior"
 require "rails/generators/testing/assertions"
+require "minitest"
 require "minitest/assertions"
 require "fileutils"