module RailsAiAdmin::RecordVersion

The optimistic version a form, intent, selection or work item carries for one record. Models with Rails optimistic locking use lock_version. Other models use updated_at, as whole microseconds since the epoch, compared after the record is loaded with a row lock inside the write transaction.

Constants

STRATEGIES

Public Instance Methods

column (model)

Source

# File lib/rails_ai_admin/record_version.rb, line 38
  def column(model) = strategy(model)&.to_s
end

The column a resource must never let a person write directly.

of (record)

Source

# File lib/rails_ai_admin/record_version.rb, line 27
def of(record)
  case strategy(record.class)
  when :lock_version then record.lock_version
  when :updated_at
    time = record.read_attribute("updated_at")
    time.nil? ? 0 : (time.to_r * 1_000_000).to_i
  else raise ConfigurationError, "Writes require lock_version or an updated_at timestamp"
  end
end

A nonnegative Integer. A record whose updated_at is still NULL is version 0 until its first write sets it.

strategy (model)

Source

# File lib/rails_ai_admin/record_version.rb, line 14
def strategy(model)
  return :lock_version if model.locking_enabled? && model.locking_column == "lock_version"
  column = model.columns_hash["updated_at"]
  return :updated_at if column && %i[datetime timestamp].include?(column.type) && model.record_timestamps
  nil
end

:lock_version, :updated_at or nil when the model cannot carry a version.

supported? (model)

Source

# File lib/rails_ai_admin/record_version.rb, line 21
def supported?(model)
  !strategy(model).nil? && !model.composite_primary_key?
end