Add SQLite support

- UUID support
- Schema compatibility layer, ignore MySQL specific options
- Search not working yet

config/database.yml

@@ -1,4 +1,7 @@
 <%
+  database_adapter = ENV.fetch("DATABASE_ADAPTER", "mysql")
+  use_sqlite = database_adapter == "sqlite"
+
   if ENV["MIGRATE"].present?
     mysql_app_user_key = "MYSQL_ALTER_USER"
     mysql_app_password_key = "MYSQL_ALTER_PASSWORD"
@@ -12,13 +15,24 @@
 %>
 
 default: &default
+  <% if use_sqlite %>
+  adapter: sqlite3
+  pool: 50
+  timeout: 5000
+  <% else %>
   adapter: trilogy
   host: <%= ENV.fetch "FIZZY_DB_HOST", "127.0.0.1" %>
   port: <%= ENV.fetch "FIZZY_DB_PORT", 3306 %>
   pool: 50
   timeout: 5000
+  <% end %>
 
 development:
+  <% if use_sqlite %>
+  primary:
+    <<: *default
+    database: db/development.sqlite3
+  <% else %>
   primary:
     <<: *default
     database: fizzy_development
@@ -26,28 +40,34 @@ development:
   replica:
     <<: *default
     database: fizzy_development
-    replica: true
     port: <%= ENV.fetch "FIZZY_DB_PORT", 33380 %>
+    replica: true
   cable:
     <<: *default
     database: development_cable
-    migrations_paths: db/cable_migrate
     port: <%= ENV.fetch "FIZZY_DB_PORT", 33380 %>
+    migrations_paths: db/cable_migrate
   cache:
     <<: *default
     database: development_cache
-    migrations_paths: db/cache_migrate
     port: <%= ENV.fetch "FIZZY_DB_PORT", 33380 %>
+    migrations_paths: db/cache_migrate
   queue:
     <<: *default
     database: development_queue
-    migrations_paths: db/queue_migrate
     port: <%= ENV.fetch "FIZZY_DB_PORT", 33380 %>
+    migrations_paths: db/queue_migrate
+  <% end %>
 
 # Warning: The database defined as "test" will be erased and
 # re-generated from your development database when you run "rake".
 # Do not set this db to the same as development or production.
 test:
+  <% if use_sqlite %>
+  primary:
+    <<: *default
+    database: db/test.sqlite3
+  <% else %>
   primary:
     <<: *default
     database: fizzy_test
@@ -57,6 +77,7 @@ test:
     database: fizzy_test
     port: <%= ENV.fetch "FIZZY_DB_PORT", 33380 %>
     replica: true
+  <% end %>
 
 production: &production
   primary:

config/initializers/active_storage.rb

@@ -6,7 +6,12 @@ end
 
 # Use DB read/write splitting for Active Storage models
 ActiveSupport.on_load(:active_storage_record) do
-  connects_to database: { writing: :primary, reading: :replica }
+  # SQLite doesn't use separate replica databases
+  if ENV.fetch("DATABASE_ADAPTER", "mysql") == "sqlite"
+    connects_to database: { writing: :primary, reading: :primary }
+  else
+    connects_to database: { writing: :primary, reading: :replica }
+  end
 end
 
 module ActiveStorageControllerExtensions

config/initializers/sqlite_compatibility.rb

@@ -0,0 +1,54 @@
+# SQLite compatibility layer - filters out MySQL-specific options when using SQLite
+
+# Define modules outside on_load so they're available immediately
+module SQLiteCompatibility
+  module SQLiteTableDefinitionCompatibility
+    # Override column method to filter out MySQL-specific options
+    def column(name, type, **options)
+      # Check if we're using SQLite by checking the connection adapter
+      if @conn.is_a?(ActiveRecord::ConnectionAdapters::SQLite3Adapter)
+        # Remove MySQL-specific options that SQLite doesn't support
+        options = options.except(:size, :charset, :collation, :unsigned)
+      end
+      super(name, type, **options)
+    end
+
+    # Override index method to filter out MySQL-specific index options
+    def index(column_name, **options)
+      if @conn.is_a?(ActiveRecord::ConnectionAdapters::SQLite3Adapter)
+        # Skip fulltext indexes entirely for SQLite
+        return if options[:type] == :fulltext
+        # SQLite doesn't support length-limited indexes
+        options = options.except(:length)
+      end
+      super(column_name, **options)
+    end
+  end
+
+  module SQLiteSchemaStatementCompatibility
+    # Override create_table to filter out MySQL-specific table options
+    def create_table(table_name, **options)
+      if is_a?(ActiveRecord::ConnectionAdapters::SQLite3Adapter)
+        # Remove MySQL-specific table options
+        options = options.except(:charset, :collation)
+      end
+      super(table_name, **options)
+    end
+  end
+end
+
+# Apply the prepends - both in on_load callback and immediately
+def apply_sqlite_compatibility
+  if defined?(ActiveRecord::ConnectionAdapters::SQLite3Adapter)
+    ActiveRecord::ConnectionAdapters::TableDefinition.prepend(SQLiteCompatibility::SQLiteTableDefinitionCompatibility)
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.prepend(SQLiteCompatibility::SQLiteSchemaStatementCompatibility)
+  end
+end
+
+# Run immediately if ActiveRecord is already loaded
+apply_sqlite_compatibility
+
+# Also run when ActiveRecord loads (for cases where it loads later)
+ActiveSupport.on_load(:active_record) do
+  apply_sqlite_compatibility
+end

config/initializers/uuid_primary_keys.rb

@@ -16,7 +16,42 @@ ActiveSupport.on_load(:active_record) do
     end
   end
 
-  ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter.prepend(MysqlUuidAdapter)
+  if defined?(ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter)
+    ActiveRecord::ConnectionAdapters::AbstractMysqlAdapter.prepend(MysqlUuidAdapter)
+  end
+
+  module SqliteUuidAdapter
+    # Add UUID to SQLite's native database types
+    def native_database_types
+      @native_database_types_with_uuid ||= super.merge(uuid: { name: "blob", limit: 16 })
+    end
+
+    # Override lookup_cast_type to recognize BLOB as UUID type
+    def lookup_cast_type(sql_type)
+      if sql_type == "blob(16)"
+        ActiveRecord::Type.lookup(:uuid, adapter: :sqlite3)
+      else
+        super
+      end
+    end
+
+    # Override fetch_type_metadata to preserve UUID type and limit
+    def fetch_type_metadata(sql_type)
+      if sql_type == "blob(16)"
+        ActiveRecord::ConnectionAdapters::SqlTypeMetadata.new(
+          sql_type: sql_type,
+          type: :uuid,
+          limit: 16
+        )
+      else
+        super
+      end
+    end
+  end
+
+  if defined?(ActiveRecord::ConnectionAdapters::SQLite3Adapter)
+    ActiveRecord::ConnectionAdapters::SQLite3Adapter.prepend(SqliteUuidAdapter)
+  end
 
   module SchemaDumperUuidType
     # Map binary(16) columns to :uuid type in schema.rb
@@ -29,7 +64,9 @@ ActiveSupport.on_load(:active_record) do
     end
   end
 
-  ActiveRecord::ConnectionAdapters::MySQL::SchemaDumper.prepend(SchemaDumperUuidType)
+  if defined?(ActiveRecord::ConnectionAdapters::MySQL::SchemaDumper)
+    ActiveRecord::ConnectionAdapters::MySQL::SchemaDumper.prepend(SchemaDumperUuidType)
+  end
 
   module TableDefinitionUuidSupport
     def uuid(name, **options)