debian-mirror-gitlab/lib/banzai/object_renderer.rb
2016-08-24 12:49:21 +05:30

86 lines
2.8 KiB
Ruby

module Banzai
# Class for rendering multiple objects (e.g. Note instances) in a single pass.
#
# Rendered Markdown is stored in an attribute in every object based on the
# name of the attribute containing the Markdown. For example, when the
# attribute `note` is rendered the HTML is stored in `note_html`.
class ObjectRenderer
attr_reader :project, :user
# Make sure to set the appropriate pipeline in the `raw_context` attribute
# (e.g. `:note` for Note instances).
#
# project - A Project to use for rendering and redacting Markdown.
# user - The user viewing the Markdown/HTML documents, if any.
# context - A Hash containing extra attributes to use in the rendering
# pipeline.
def initialize(project, user = nil, raw_context = {})
@project = project
@user = user
@raw_context = raw_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_objects(objects, attribute)
redacted = redact_documents(documents)
objects.each_with_index do |object, index|
redacted_data = redacted[index]
object.__send__("#{attribute}_html=", redacted_data[:document].to_html.html_safe)
object.user_visible_reference_count = redacted_data[:visible_reference_count]
end
end
# Renders the attribute of every given object.
def render_objects(objects, attribute)
render_attributes(objects, attribute)
end
# Redacts the list of documents.
#
# Returns an Array containing the redacted documents.
def redact_documents(documents)
redactor = Redactor.new(project, user)
redactor.redact(documents)
end
# Returns a Banzai context for the given object and attribute.
def context_for(object, attribute)
context = base_context.merge(cache_key: [object, attribute])
if object.respond_to?(:author)
context[:author] = object.author
end
context
end
# Renders the attributes of a set of objects.
#
# Returns an Array of `Nokogiri::HTML::Document`.
def render_attributes(objects, attribute)
strings_and_contexts = objects.map do |object|
context = context_for(object, attribute)
string = object.__send__(attribute)
{ text: string, context: context }
end
Banzai.cache_collection_render(strings_and_contexts).each_with_index.map do |html, index|
Banzai::Pipeline[:relative_link].to_document(html, strings_and_contexts[index][:context])
end
end
def base_context
@base_context ||= @raw_context.merge(current_user: user, project: project)
end
end
end