- # Inserts middleware to perform automatic connection switching.
- # The `database_selector` hash is used to pass options to the DatabaseSelector
- # middleware. The `delay` is used to determine how long to wait after a write
- # to send a subsequent read to the primary.
- #
- # The `database_resolver` class is used by the middleware to determine which
- # database is appropriate to use based on the time delay.
- #
- # The `database_resolver_context` class is used by the middleware to set
- # timestamps for the last write to the primary. The resolver uses the context
- # class timestamps to determine how long to wait before reading from the
- # replica.
- #
- # By default Rails will store a last write timestamp in the session. The
- # DatabaseSelector middleware is designed as such you can define your own
- # strategy for connection switching and pass that into the middleware through
- # these configuration options.
- # config.active_record.database_selector = { delay: 2.seconds }
- # config.active_record.database_resolver = ActiveRecord::Middleware::DatabaseSelector::Resolver
- # config.active_record.database_resolver_context = ActiveRecord::Middleware::DatabaseSelector::Resolver::Session
-