class ViewModel::DownMigrator

down migrations find a reverse path from the current schema version to the specific version requested by the client.

Private Instance Methods

migrate_viewmodel!(view_name, source_version, view_hash, references) click to toggle source
# File lib/view_model/migrator.rb, line 105
def migrate_viewmodel!(view_name, source_version, view_hash, references)
  path = @paths[view_name]
  return false unless path

  # In a serialized output, the source version should always be the present
  # and the current version, unless already modified by a parent migration
  required_version, current_version = @versions[view_name]
  return false if source_version == required_version

  unless source_version == current_version
    raise ViewModel::Migration::UnspecifiedVersionError.new(view_name, source_version)
  end

  path.reverse_each do |migration|
    migration.down(view_hash, references)
  end

  view_hash[ViewModel::VERSION_ATTRIBUTE] = required_version

  true
end