debian-mirror-gitlab/app/models/concerns/cache_markdown_field.rb
2021-11-11 11:23:49 +05:30

227 lines
7.9 KiB
Ruby

# frozen_string_literal: true
# This module takes care of updating cache columns for Markdown-containing
# fields. Use like this in the body of your class:
#
# include CacheMarkdownField
# cache_markdown_field :foo
# cache_markdown_field :bar
# cache_markdown_field :baz, pipeline: :single_line
# cache_markdown_field :baz, whitelisted: true
#
# Corresponding foo_html, bar_html and baz_html fields should exist.
module CacheMarkdownField
extend ActiveSupport::Concern
# changes to these attributes cause the cache to be invalidates
INVALIDATED_BY = %w[author project].freeze
def skip_project_check?
false
end
def can_cache_field?(field)
true
end
# Returns the default Banzai render context for the cached markdown field.
def banzai_render_context(field)
raise ArgumentError, "Unknown field: #{field.inspect}" unless
cached_markdown_fields.key?(field)
# Always include a project key, or Banzai complains
project = self.project if self.respond_to?(:project)
group = self.group if self.respond_to?(:group)
context = cached_markdown_fields[field].merge(project: project, group: group)
# Banzai is less strict about authors, so don't always have an author key
context[:author] = self.author if self.respond_to?(:author)
context[:markdown_engine] = :common_mark
if Feature.enabled?(:personal_snippet_reference_filters, context[:author])
context[:user] = self.parent_user
end
context
end
def rendered_field_content(markdown_field)
return unless can_cache_field?(markdown_field)
options = { skip_project_check: skip_project_check? }
Banzai::Renderer.cacheless_render_field(self, markdown_field, options)
end
# Update every applicable column in a row if any one is invalidated, as we only store
# one version per row
def refresh_markdown_cache
updates = cached_markdown_fields.markdown_fields.to_h do |markdown_field|
[
cached_markdown_fields.html_field(markdown_field),
rendered_field_content(markdown_field)
]
end
updates['cached_markdown_version'] = latest_cached_markdown_version
updates.each { |field, data| write_markdown_field(field, data) }
end
def refresh_markdown_cache!
updates = refresh_markdown_cache
if updates.present? && save_markdown(updates)
# save_markdown updates DB columns directly, so compute and save mentions
# by calling store_mentions! or we end-up with missing mentions although those
# would appear in the notes, descriptions, etc in the UI
store_mentions! if mentionable_attributes_changed?(updates)
end
end
def cached_html_up_to_date?(markdown_field)
return false if cached_html_for(markdown_field).nil? && __send__(markdown_field).present? # rubocop:disable GitlabSecurity/PublicSend
html_field = cached_markdown_fields.html_field(markdown_field)
markdown_changed = markdown_field_changed?(markdown_field)
html_changed = markdown_field_changed?(html_field)
latest_cached_markdown_version == cached_markdown_version &&
(html_changed || markdown_changed == html_changed)
end
def invalidated_markdown_cache?
cached_markdown_fields.html_fields.any? {|html_field| attribute_invalidated?(html_field) }
end
def attribute_invalidated?(attr)
__send__("#{attr}_invalidated?") # rubocop:disable GitlabSecurity/PublicSend
end
def cached_html_for(markdown_field)
raise ArgumentError, "Unknown field: #{markdown_field}" unless
cached_markdown_fields.key?(markdown_field)
__send__(cached_markdown_fields.html_field(markdown_field)) # rubocop:disable GitlabSecurity/PublicSend
end
# Updates the markdown cache if necessary, then returns the field
# Unlike `cached_html_for` it returns `nil` if the field does not exist
def updated_cached_html_for(markdown_field)
return unless cached_markdown_fields.key?(markdown_field)
if attribute_invalidated?(cached_markdown_fields.html_field(markdown_field))
# Invalidated due to Markdown content change
# We should not persist the updated HTML here since this will depend on whether the
# Markdown content change will be persisted. Both will be persisted together when the model is saved.
if changed_attributes.key?(markdown_field)
refresh_markdown_cache
else
# Invalidated due to stale HTML cache
# This could happen when the Markdown cache version is bumped or when a model is imported and the HTML is empty.
# We persist the updated HTML here so that subsequent calls to this method do not have to regenerate the HTML again.
refresh_markdown_cache!
end
end
cached_html_for(markdown_field)
end
def latest_cached_markdown_version
@latest_cached_markdown_version ||= (Gitlab::MarkdownCache::CACHE_COMMONMARK_VERSION << 16) | local_version
end
def local_version
# because local_markdown_version is stored in application_settings which
# uses cached_markdown_version too, we check explicitly to avoid
# endless loop
return local_markdown_version if respond_to?(:has_attribute?) && has_attribute?(:local_markdown_version)
settings = Gitlab::CurrentSettings.current_application_settings
# Following migrations are not properly isolated and
# use real models (by calling .ghost method), in these migrations
# local_markdown_version attribute doesn't exist yet, so we
# use a default value:
# db/migrate/20170825104051_migrate_issues_to_ghost_user.rb
# db/migrate/20171114150259_merge_requests_author_id_foreign_key.rb
if settings.respond_to?(:local_markdown_version)
settings.local_markdown_version
else
0
end
end
def parent_user
nil
end
def store_mentions!
# We can only store mentions if the mentionable is a database object
return unless self.is_a?(ApplicationRecord)
identifier = user_mention_identifier
# this may happen due to notes polymorphism, so noteable_id may point to a record
# that no longer exists as we cannot have FK on noteable_id
return if identifier.blank?
refs = all_references(self.author)
references = {}
references[:mentioned_users_ids] = refs.mentioned_user_ids.presence
references[:mentioned_groups_ids] = refs.mentioned_group_ids.presence
references[:mentioned_projects_ids] = refs.mentioned_project_ids.presence
if references.compact.any?
user_mention_class.upsert(references.merge(identifier), unique_by: identifier.compact.keys)
else
user_mention_class.delete_by(identifier)
end
true
end
def mentionable_attributes_changed?(changes = saved_changes)
return false unless is_a?(Mentionable)
self.class.mentionable_attrs.any? do |attr|
changes.key?(cached_markdown_fields.html_field(attr.first)) &&
changes.fetch(cached_markdown_fields.html_field(attr.first)).last.present?
end
end
included do
cattr_reader :cached_markdown_fields do
Gitlab::MarkdownCache::FieldData.new
end
if self < ActiveRecord::Base
include Gitlab::MarkdownCache::ActiveRecord::Extension
else
prepend Gitlab::MarkdownCache::Redis::Extension
end
end
class_methods do
private
# Specify that a field is markdown. Its rendered output will be cached in
# a corresponding _html field. Any custom rendering options may be provided
# as a context.
def cache_markdown_field(markdown_field, context = {})
cached_markdown_fields[markdown_field] = context
html_field = cached_markdown_fields.html_field(markdown_field)
invalidation_method = "#{html_field}_invalidated?".to_sym
# The HTML becomes invalid if any dependent fields change. For now, assume
# author and project invalidate the cache in all circumstances.
define_method(invalidation_method) do
changed_fields = changed_attributes.keys
invalidations = changed_fields & [markdown_field.to_s, *INVALIDATED_BY]
!invalidations.empty? || !cached_html_up_to_date?(markdown_field)
end
end
end
end