Separate the cache database

config/application.rb

@@ -28,6 +28,7 @@ module BlackCandy
   include BlackCandy::Configurable
 
   has_config :db_url
+  has_config :cache_db_url
   has_config :media_path
   has_config :db_adapter, default: "sqlite"
   has_config :nginx_sendfile, default: false
@@ -39,8 +40,10 @@ module BlackCandy
       raise_config_validation_error "Unsupported database adapter."
     end
 
-    if value == "postgresql" && ENV["RAILS_ENV"] == "production" && config.db_url.blank?
-      raise_config_validation_error "DB_URL is required if database adapter is postgresql"
+    if value == "postgresql" &&
+        ENV["RAILS_ENV"] == "production" &&
+        (config.db_url.blank? || config.cache_db_url.blank?)
+      raise_config_validation_error "DB_URL and CACHE_DB_URL are required if database adapter is postgresql"
     end
   end
 

config/cache.yml

@@ -0,0 +1,16 @@
+default: &default
+  database: cache
+  store_options:
+    # Cap age of oldest cache entry to fulfill retention policies
+    # max_age: <%= 60.days.to_i %>
+    max_size: <%= 256.megabytes %>
+    namespace: <%= Rails.env %>
+
+development:
+  <<: *default
+
+test:
+  <<: *default
+
+production:
+  <<: *default

config/database.yml

@@ -11,32 +11,62 @@ pg_default: &pg_default
 
 <% if BlackCandy.config.db_adapter == "postgresql" %>
 development:
-  <<: *pg_default
-  username: <%= ENV['DB_USERNAME'] %>
-  password: <%= ENV['DB_PASSWORD'] %>
-  database: blackcandy_development
-  host: localhost
+  primary: &primary_development
+    <<: *pg_default
+    username: <%= ENV['DB_USERNAME'] %>
+    password: <%= ENV['DB_PASSWORD'] %>
+    database: blackcandy_development
+    host: localhost
+  cache:
+    <<: *primary_development
+    database: blackcandy_development_cache
+    migrations_paths: db/cache_migrate
 
 test:
-  <<: *pg_default
-  username: <%= ENV['DB_USERNAME'] %>
-  password: <%= ENV['DB_PASSWORD'] %>
-  database: blackcandy_test
-  host: localhost
+  primary: &primary_test
+    <<: *pg_default
+    username: <%= ENV['DB_USERNAME'] %>
+    password: <%= ENV['DB_PASSWORD'] %>
+    database: blackcandy_test
+    host: localhost
+  cache:
+    <<: *primary_test
+    database: blackcandy_test_cache
+    migrations_paths: db/cache_migrate
 
 production:
-  <<: *pg_default
-  url: <%= BlackCandy.config.db_url %>
+  primary: &primary_production
+    <<: *pg_default
+    url: <%= BlackCandy.config.db_url %>
+  cache:
+    <<: *primary_production
+    url: <%= BlackCandy.config.cache_db_url %>
+    migrations_paths: db/cache_migrate
 <% else %>
 development:
-  <<: *sqlite_default
-  database: storage/development.sqlite3
+  primary:
+    <<: *sqlite_default
+    database: storage/development.sqlite3
+  cache:
+    <<: *sqlite_default
+    database: storage/development_cache.sqlite3
+    migrations_paths: db/cache_migrate
 
 test:
-  <<: *sqlite_default
-  database: storage/test.sqlite3
+  primary:
+    <<: *sqlite_default
+    database: storage/test.sqlite3
+  cache:
+    <<: *sqlite_default
+    database: storage/test_cache.sqlite3
+    migrations_paths: db/cache_migrate
 
 production:
-  <<: *sqlite_default
-  database: storage/production.sqlite3
+  primary:
+    <<: *sqlite_default
+    database: storage/production.sqlite3
+  cache:
+    <<: *sqlite_default
+    database: storage/production_cache.sqlite3
+    migrations_paths: db/cache_migrate
 <% end %>

db/cache_schema.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+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/20241016135211_drop_solid_cache_entries_table.rb

@@ -0,0 +1,14 @@
+class DropSolidCacheEntriesTable < ActiveRecord::Migration[7.2]
+  def change
+    drop_table :solid_cache_entries 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[7.1].define(version: 2024_02_06_051609) do
+ActiveRecord::Schema[7.2].define(version: 2024_10_16_135211) do
   create_table "active_storage_attachments", force: :cascade do |t|
     t.string "name", null: false
     t.string "record_type", null: false
@@ -91,17 +91,6 @@
     t.index ["singleton_guard"], name: "index_settings_on_singleton_guard", unique: true
   end
 
-  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
-
   create_table "solid_queue_blocked_executions", force: :cascade do |t|
     t.integer "job_id", null: false
     t.string "queue_name", null: false

test/lib/black_candy/config_test.rb

@@ -61,7 +61,7 @@ class BlackCandy::ConfigTest < ActiveSupport::TestCase
       end
     end
 
-    with_env("DB_ADAPTER" => "postgresql", "DB_URL" => "database_url", "RAILS_ENV" => "production") do
+    with_env("DB_ADAPTER" => "postgresql", "DB_URL" => "database_url", "CACHE_DB_URL" => "cache_db_url", "RAILS_ENV" => "production") do
       assert_equal "postgresql", BlackCandy.config.db_adapter
     end
   end