module Banzai # Class for rendering multiple objects (e.g. Note instances) in a single pass, # using +render_field+ to benefit from caching in the database. Rendering and # redaction are both performed. # # The unredacted HTML is generated according to the usual +render_field+ # policy, so specify the pipeline and any other context options on the model. # # The *redacted* (i.e., suitable for use) HTML is placed in an attribute # named "redacted_", where is the name of the cache field for the # chosen attribute. # # As an example, rendering the attribute `note` would place the unredacted # HTML into `note_html` and the redacted HTML into `redacted_note_html`. class ObjectRenderer attr_reader :context # default_project - A default Project to use for redacting Markdown. # user - The user viewing the Markdown/HTML documents, if any. # redaction_context - A Hash containing extra attributes to use during redaction def initialize(default_project: nil, user: nil, redaction_context: {}) @context = RenderContext.new(default_project, user) @redaction_context = base_context.merge(redaction_context) end # Renders and redacts an Array of objects. # # objects - The objects to render. # attribute - The attribute containing the raw Markdown to render. # # Returns the same input objects. def render(objects, attribute) documents = render_documents(objects, attribute) documents = post_process_documents(documents, objects, attribute) redacted = redact_documents(documents) objects.each_with_index do |object, index| redacted_data = redacted[index] object.__send__("redacted_#{attribute}_html=", redacted_data[:document].to_html(save_options).html_safe) # rubocop:disable GitlabSecurity/PublicSend object.user_visible_reference_count = redacted_data[:visible_reference_count] if object.respond_to?(:user_visible_reference_count) end end private def render_documents(objects, attribute) pipeline = HTML::Pipeline.new([]) objects.map do |object| document = pipeline.to_document(Banzai.render_field(object, attribute)) context.associate_document(document, object) document end end def post_process_documents(documents, objects, attribute) # Called here to populate cache, refer to IssuableExtractor docs IssuableExtractor.new(context).extract(documents) documents.zip(objects).map do |document, object| pipeline_context = context_for(document, object, attribute) Banzai::Pipeline[:post_process].to_document(document, pipeline_context) end end # Redacts the list of documents. # # Returns an Array containing the redacted documents. def redact_documents(documents) redactor = Redactor.new(context) redactor.redact(documents) end # Returns a Banzai context for the given object and attribute. def context_for(document, object, attribute) @redaction_context.merge(object.banzai_render_context(attribute)).merge( project: context.project_for_node(document) ) end def base_context { current_user: context.current_user, skip_redaction: true } end def save_options return {} unless @redaction_context[:xhtml] { save_with: Nokogiri::XML::Node::SaveOptions::AS_XHTML } end end end