Support Markdown rendering using multiple projectsrendering-markdown-multiple-projects

This refactors the Markdown pipeline so it supports the rendering of
multiple documents that may belong to different projects. An example of
where this happens is when displaying the event feed of a group. In this
case we retrieve events for all projects in the group. Previously we
would group events per project and render these chunks separately, but
this would result in many SQL queries being executed. By extending the
Markdown pipeline to support this out of the box we can drastically
reduce the number of SQL queries.

To achieve this we introduce a new object to the pipeline:
Banzai::RenderContext. This object simply wraps two other objects: an
optional Project instance, and an optional User instance. On its own
this wouldn't be very helpful, but a RenderContext can also be used to
associate HTML documents with specific Project instances. This work is
done in Banzai::ObjectRenderer and allows us to reuse as many queries
(and results) as possible.

7 files changed, 21 insertions, 18 deletions

diff --git a/app/controllers/concerns/notes_actions.rb b/app/controllers/concerns/notes_actions.rb
index 839cac3687c..ad4e936a3d4 100644
--- a/app/controllers/concerns/notes_actions.rb
+++ b/app/controllers/concerns/notes_actions.rb
@@ -41,7 +41,7 @@ module NotesActions
     @note = Notes::CreateService.new(note_project, current_user, create_params).execute
 
     if @note.is_a?(Note)
-      Notes::RenderService.new(current_user).execute([@note], @project)
+      Notes::RenderService.new(current_user).execute([@note])
     end
 
     respond_to do |format|
@@ -56,7 +56,7 @@ module NotesActions
     @note = Notes::UpdateService.new(project, current_user, note_params).execute(note)
 
     if @note.is_a?(Note)
-      Notes::RenderService.new(current_user).execute([@note], @project)
+      Notes::RenderService.new(current_user).execute([@note])
     end
 
     respond_to do |format|
diff --git a/app/controllers/concerns/renders_notes.rb b/app/controllers/concerns/renders_notes.rb
index e7ef297879f..36e3d76ecfe 100644
--- a/app/controllers/concerns/renders_notes.rb
+++ b/app/controllers/concerns/renders_notes.rb
@@ -4,7 +4,7 @@ module RendersNotes
     preload_noteable_for_regular_notes(notes)
     preload_max_access_for_authors(notes, @project)
     preload_first_time_contribution_for_authors(noteable, notes)
-    Notes::RenderService.new(current_user).execute(notes, @project)
+    Notes::RenderService.new(current_user).execute(notes)
 
     notes
   end
diff --git a/app/controllers/groups_controller.rb b/app/controllers/groups_controller.rb
index 283c3e5f1e0..5ac4b8710e2 100644
--- a/app/controllers/groups_controller.rb
+++ b/app/controllers/groups_controller.rb
@@ -173,7 +173,9 @@ class GroupsController < Groups::ApplicationController
       .new(@projects, offset: params[:offset].to_i, filter: event_filter)
       .to_a
 
-    Events::RenderService.new(current_user).execute(@events, atom_request: request.format.atom?)
+    Events::RenderService
+      .new(current_user)
+      .execute(@events, atom_request: request.format.atom?)
   end
 
   def user_actions
diff --git a/app/controllers/projects/notes_controller.rb b/app/controllers/projects/notes_controller.rb
index dd41b9648e8..86c50d88a2a 100644
--- a/app/controllers/projects/notes_controller.rb
+++ b/app/controllers/projects/notes_controller.rb
@@ -68,7 +68,7 @@ class Projects::NotesController < Projects::ApplicationController
   private
 
   def render_json_with_notes_serializer
-    Notes::RenderService.new(current_user).execute([note], project)
+    Notes::RenderService.new(current_user).execute([note])
 
     render json: note_serializer.represent(note)
   end
diff --git a/app/helpers/markup_helper.rb b/app/helpers/markup_helper.rb
index 2fe1927a189..39e7a7fd396 100644
--- a/app/helpers/markup_helper.rb
+++ b/app/helpers/markup_helper.rb
@@ -256,7 +256,7 @@ module MarkupHelper
     return '' unless html.present?
 
     context.merge!(
-      current_user:   (current_user if defined?(current_user)),
+      current_user: (current_user if defined?(current_user)),
 
       # RelativeLinkFilter
       commit:         @commit,
diff --git a/app/services/events/render_service.rb b/app/services/events/render_service.rb
index 0b62d8aedf1..bb72d7685dd 100644
--- a/app/services/events/render_service.rb
+++ b/app/services/events/render_service.rb
@@ -1,15 +1,17 @@
 module Events
   class RenderService < BaseRenderer
     def execute(events, atom_request: false)
-      events.map(&:note).compact.group_by(&:project).each do |project, notes|
-        render_notes(notes, project, atom_request)
-      end
+      notes = events.map(&:note).compact
+
+      render_notes(notes, atom_request)
     end
 
     private
 
-    def render_notes(notes, project, atom_request)
-      Notes::RenderService.new(current_user).execute(notes, project, render_options(atom_request))
+    def render_notes(notes, atom_request)
+      Notes::RenderService
+        .new(current_user)
+        .execute(notes, render_options(atom_request))
     end
 
     def render_options(atom_request)
diff --git a/app/services/notes/render_service.rb b/app/services/notes/render_service.rb
index a77e98c2b07..efc9d6da2aa 100644
--- a/app/services/notes/render_service.rb
+++ b/app/services/notes/render_service.rb
@@ -3,19 +3,18 @@ module Notes
     # Renders a collection of Note instances.
     #
     # notes - The notes to render.
-    # project - The project to use for redacting.
-    # user - The user viewing the notes.
-
+    #
     # Possible options:
+    #
     # requested_path - The request path.
     # project_wiki - The project's wiki.
     # ref - The current Git reference.
     # only_path - flag to turn relative paths into absolute ones.
     # xhtml - flag to save the html in XHTML
-    def execute(notes, project, **opts)
-      renderer = Banzai::ObjectRenderer.new(project, current_user, **opts)
-
-      renderer.render(notes, :note)
+    def execute(notes, options = {})
+      Banzai::ObjectRenderer
+        .new(user: current_user, redaction_context: options)
+        .render(notes, :note)
     end
   end
 end