Class: ActiveRecord::Materialized::Reconciler Private

Inherits:
Object
  • Object
show all
Defined in:
lib/activerecord/materialized/reconciler.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Bounds a view's staleness in time: verifies its materialized contents against the source (via DataVerifier) and repairs whatever the change source missed, using SCOPED maintenance — never a full rebuild. Meant to run on a schedule as a backstop for writes any change source can miss (a bulk/raw write, a dropped or lagging CDC event).

Safe alongside normal refresh. It drains pending maintenance first, so remaining drift is genuinely missed writes rather than un-applied maintenance, then repairs through the same guarded, transactional maintenance path. When a refresh is already in flight it defers to the next tick rather than verifying a cache mid-mutation or racing that cycle's payload — so it can neither corrupt the cache nor double-maintain.

Instance Method Summary collapse

Constructor Details

#initialize(view_class, mode: :checksum, sample: nil) ⇒ Reconciler

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of Reconciler.



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# File 'lib/activerecord/materialized/reconciler.rb', line 20

def initialize(view_class, mode: :checksum, sample: nil)
  @view_class = view_class
  @mode = mode
  @sample = sample
end

Instance Method Details

#reconcile! ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future. 



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# File 'lib/activerecord/materialized/reconciler.rb', line 26

def reconcile!
  # Route the whole cycle to the writer so the repair writes (merge!/mark_reconciled!/refresh!)
  # land on the primary; DataVerifier.verify nests its own reading role, so verification still
  # reads from the replica while repair stays on the primary.
  ConnectionRouting.maintenance do
    divergent = []
    next emit(build) unless @view_class.materialized? # cold view: no cache to verify or repair

    @view_class.refresh! # drain pending maintenance so any remaining drift is genuine
    divergent = detect_drift
    repair!(divergent) unless divergent.empty?
    mark_reconciled!(divergent)
    emit(build(repaired_keys: divergent))
  rescue Refresher::AlreadyRefreshingError
    # A live refresh owns the cycle; the scoped repair we queued (if any) drains on
    # that cycle or the next tick. Defer without corrupting or double-maintaining.
    emit(build(repaired_keys: divergent || [], deferred: true))
  end
end