mastodon/app/controllers/concerns/cache_concern.rb
Akihiko Odaki 64ef37b89d
Introduce ApplicationController#cache_collection_paginated_by_id (#14677)
* Replace incorrect use of distinct with group

Some uses of ActiveRecord::QueryMethods#distinct pass field names but they
are incorrect for the current version of Rails.

ActiveRecord::QueryMethods#group provides the expected behavior and
benefits performance. See commit 6da24aad4cafdef8d8a2c92bac2002a5fc2fe9c8.

* Introduce ApplicationController#cache_collection_paginated_by_id

ApplicationController#cache_collection_paginated_by_id fuses
ApplicationController#cache_collection and Paginable.paginate_by_id.

An advantage of this method is that it prevents from modifying scope which
Paginable.paginate_by_id may provide.
ApplicationController#cache_collection always return an array and there
is no possibility of the scope modification. It is also clear for a
programmer, considering the implication of "cache".

This method can also emit more efficient queries by using
Cacheable.cache_ids before calling Paginable.paginate_by_id.
2020-08-28 12:31:56 +02:00

55 lines
2 KiB
Ruby

# frozen_string_literal: true
module CacheConcern
extend ActiveSupport::Concern
def render_with_cache(**options)
raise ArgumentError, 'only JSON render calls are supported' unless options.key?(:json) || block_given?
key = options.delete(:key) || [[params[:controller], params[:action]].join('/'), options[:json].respond_to?(:cache_key) ? options[:json].cache_key : nil, options[:fields].nil? ? nil : options[:fields].join(',')].compact.join(':')
expires_in = options.delete(:expires_in) || 3.minutes
body = Rails.cache.read(key, raw: true)
if body
render(options.except(:json, :serializer, :each_serializer, :adapter, :fields).merge(json: body))
else
if block_given?
options[:json] = yield
elsif options[:json].is_a?(Symbol)
options[:json] = send(options[:json])
end
render(options)
Rails.cache.write(key, response.body, expires_in: expires_in, raw: true)
end
end
def set_cache_headers
response.headers['Vary'] = public_fetch_mode? ? 'Accept' : 'Accept, Signature'
end
def cache_collection(raw, klass)
return raw unless klass.respond_to?(:with_includes)
raw = raw.cache_ids.to_a if raw.is_a?(ActiveRecord::Relation)
cached_keys_with_value = Rails.cache.read_multi(*raw).transform_keys(&:id)
uncached_ids = raw.map(&:id) - cached_keys_with_value.keys
klass.reload_stale_associations!(cached_keys_with_value.values) if klass.respond_to?(:reload_stale_associations!)
unless uncached_ids.empty?
uncached = klass.where(id: uncached_ids).with_includes.each_with_object({}) { |item, h| h[item.id] = item }
uncached.each_value do |item|
Rails.cache.write(item, item)
end
end
raw.map { |item| cached_keys_with_value[item.id] || uncached[item.id] }.compact
end
def cache_collection_paginated_by_id(raw, klass, limit, options)
cache_collection raw.cache_ids.paginate_by_id(limit, options), klass
end
end