Merge branch 'refactor-rendering-redacting' into 'master'

Support for rendering/redacting multiple documents

See merge request !4828

5 files changed, 188 insertions, 28 deletions

diff --git a/lib/banzai/filter/redactor_filter.rb b/lib/banzai/filter/redactor_filter.rb
index c753a84a20d..c59a80dd1c7 100644
--- a/lib/banzai/filter/redactor_filter.rb
+++ b/lib/banzai/filter/redactor_filter.rb
@@ -7,40 +7,13 @@ module Banzai
     #
     class RedactorFilter < HTML::Pipeline::Filter
       def call
-        nodes = Querying.css(doc, 'a.gfm[data-reference-type]')
-        visible = nodes_visible_to_user(nodes)
-
-        nodes.each do |node|
-          unless visible.include?(node)
-            # The reference should be replaced by the original text,
-            # which is not always the same as the rendered text.
-            text = node.attr('data-original') || node.text
-            node.replace(text)
-          end
-        end
+        Redactor.new(project, current_user).redact([doc])
 
         doc
       end
 
       private
 
-      def nodes_visible_to_user(nodes)
-        per_type = Hash.new { |h, k| h[k] = [] }
-        visible = Set.new
-
-        nodes.each do |node|
-          per_type[node.attr('data-reference-type')] << node
-        end
-
-        per_type.each do |type, nodes|
-          parser = Banzai::ReferenceParser[type].new(project, current_user)
-
-          visible.merge(parser.nodes_visible_to_user(current_user, nodes))
-        end
-
-        visible
-      end
-
       def current_user
         context[:current_user]
       end
diff --git a/lib/banzai/note_renderer.rb b/lib/banzai/note_renderer.rb
new file mode 100644
index 00000000000..bab6a9934d1
--- /dev/null
+++ b/lib/banzai/note_renderer.rb
@@ -0,0 +1,22 @@
+module Banzai
+  module NoteRenderer
+    # Renders a collection of Note instances.
+    #
+    # notes - The notes to render.
+    # project - The project to use for rendering/redacting.
+    # user - The user viewing the notes.
+    # path - The request path.
+    # wiki - The project's wiki.
+    # git_ref - The current Git reference.
+    def self.render(notes, project, user = nil, path = nil, wiki = nil, git_ref = nil)
+      renderer = ObjectRenderer.new(project,
+                                    user,
+                                    requested_path: path,
+                                    project_wiki: wiki,
+                                    ref: git_ref,
+                                    pipeline: :note)
+
+      renderer.render(notes, :note)
+    end
+  end
+end
diff --git a/lib/banzai/object_renderer.rb b/lib/banzai/object_renderer.rb
new file mode 100644
index 00000000000..f0e4f28bf12
--- /dev/null
+++ b/lib/banzai/object_renderer.rb
@@ -0,0 +1,85 @@
+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|
+        object.__send__("#{attribute}_html=", redacted.fetch(index))
+      end
+
+      objects
+    end
+
+    # Renders the attribute of every given object.
+    def render_objects(objects, attribute)
+      objects.map do |object|
+        render_attribute(object, attribute)
+      end
+    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).map do |document|
+        document.to_html.html_safe
+      end
+    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 attribute of an object.
+    #
+    # Returns a `Nokogiri::HTML::Document`.
+    def render_attribute(object, attribute)
+      context = context_for(object, attribute)
+
+      string = object.__send__(attribute)
+      html = Banzai.render(string, context)
+
+      Banzai::Pipeline[:relative_link].to_document(html, context)
+    end
+
+    def base_context
+      @base_context ||= @raw_context.merge(current_user: user, project: project)
+    end
+  end
+end
diff --git a/lib/banzai/pipeline/relative_link_pipeline.rb b/lib/banzai/pipeline/relative_link_pipeline.rb
new file mode 100644
index 00000000000..270990e7ab4
--- /dev/null
+++ b/lib/banzai/pipeline/relative_link_pipeline.rb
@@ -0,0 +1,11 @@
+module Banzai
+  module Pipeline
+    class RelativeLinkPipeline < BasePipeline
+      def self.filters
+        FilterArray[
+          Filter::RelativeLinkFilter
+        ]
+      end
+    end
+  end
+end
diff --git a/lib/banzai/redactor.rb b/lib/banzai/redactor.rb
new file mode 100644
index 00000000000..ffd267d5e9a
--- /dev/null
+++ b/lib/banzai/redactor.rb
@@ -0,0 +1,69 @@
+module Banzai
+  # Class for removing Markdown references a certain user is not allowed to
+  # view.
+  class Redactor
+    attr_reader :user, :project
+
+    # project - A Project to use for redacting links.
+    # user - The currently logged in user (if any).
+    def initialize(project, user = nil)
+      @project = project
+      @user = user
+    end
+
+    # Redacts the references in the given Array of documents.
+    #
+    # This method modifies the given documents in-place.
+    #
+    # documents - A list of HTML documents containing references to redact.
+    #
+    # Returns the documents passed as the first argument.
+    def redact(documents)
+      nodes = documents.flat_map do |document|
+        Querying.css(document, 'a.gfm[data-reference-type]')
+      end
+
+      redact_nodes(nodes)
+
+      documents
+    end
+
+    # Redacts the given nodes
+    #
+    # nodes - An Array of HTML nodes to redact.
+    def redact_nodes(nodes)
+      visible = nodes_visible_to_user(nodes)
+
+      nodes.each do |node|
+        unless visible.include?(node)
+          # The reference should be replaced by the original text,
+          # which is not always the same as the rendered text.
+          text = node.attr('data-original') || node.text
+          node.replace(text)
+        end
+      end
+    end
+
+    # Returns the nodes visible to the current user.
+    #
+    # nodes - The input nodes to check.
+    #
+    # Returns a new Array containing the visible nodes.
+    def nodes_visible_to_user(nodes)
+      per_type = Hash.new { |h, k| h[k] = [] }
+      visible = Set.new
+
+      nodes.each do |node|
+        per_type[node.attr('data-reference-type')] << node
+      end
+
+      per_type.each do |type, nodes|
+        parser = Banzai::ReferenceParser[type].new(project, user)
+
+        visible.merge(parser.nodes_visible_to_user(user, nodes))
+      end
+
+      visible
+    end
+  end
+end