First try rendering the whole view content

app/presenters/snippet_blob_presenter.rb

 # frozen_string_literal: true
 
 class SnippetBlobPresenter < BlobPresenter
+  include Gitlab::Routing
+
   def rich_data
     return if blob.binary?
+    return unless blob.rich_viewer
 
-    if markup?
-      blob.rendered_markup
-    else
-      highlight(plain: false)
-    end
+    render_rich_partial
   end
 
   def plain_data
     return if blob.binary?
 
-    highlight(plain: !markup?)
+    highlight(plain: false)
   end
 
   def raw_path
@@ -27,10 +26,6 @@ class SnippetBlobPresenter < BlobPresenter
 
   private
 
-  def markup?
-    blob.rich_viewer&.partial_name == 'markup'
-  end
-
   def snippet
     blob.container
   end
@@ -38,4 +33,24 @@ class SnippetBlobPresenter < BlobPresenter
   def language
     nil
   end
+
+  def render_rich_partial
+    renderer.render("projects/blob/viewers/#{blob.rich_viewer.partial_name}",
+                    viewer: blob.rich_viewer,
+                    blob: blob,
+                    blow_raw_path: raw_path)
+  end
+
+  def renderer
+    ActionView::Base.new(build_lookup_context, { snippet: snippet }, ActionController::Base.new).tap do |renderer|
+      renderer.extend ApplicationController._helpers
+      renderer.class_eval do
+        include Rails.application.routes.url_helpers
+      end
+    end
+  end
+
+  def build_lookup_context
+    ActionView::Base.build_lookup_context(ActionController::Base.view_paths)
+  end
 end

spec/presenters/snippet_blob_presenter_spec.rb

@@ -4,36 +4,67 @@ require 'spec_helper'
 
 describe SnippetBlobPresenter do
   describe '#rich_data' do
-    let(:snippet) { build(:personal_snippet) }
+    let_it_be(:snippet) { create(:personal_snippet) }
+
+    before do
+      allow_next_instance_of(ActionController::Base) do |instance|
+        allow(instance).to receive(:current_user).and_return(nil)
+      end
+    end
 
     subject { described_class.new(snippet.blob).rich_data }
 
+    context 'with PersonalSnippet' do
+      let(:raw_url) { "http://127.0.0.1:3000/snippets/#{snippet.id}/raw" }
+      let(:snippet) { build(:personal_snippet) }
+
       it 'returns nil when the snippet blob is binary' do
         allow(snippet.blob).to receive(:binary?).and_return(true)
 
         expect(subject).to be_nil
       end
 
-    it 'returns markdown content when snippet file is markup' do
-      snippet.file_name = 'test.md'
-      snippet.content = '*foo*'
+      context 'with markdown format' do
+        let(:snippet) { create(:personal_snippet, file_name: 'test.md', content: '*foo*') }
 
-      expect(subject).to eq '<p data-sourcepos="1:1-1:5" dir="auto"><em>foo</em></p>'
+        it 'returns rich markdown content' do
+          expect(subject).to eq '<div class="file-content md md-file"><p data-sourcepos="1:1-1:5" dir="auto"><em>foo</em></p></div>'
+        end
       end
 
-    it 'returns syntax highlighted content' do
-      snippet.file_name = 'test.rb'
-      snippet.content = 'class Foo;end'
+      context 'with notebook format' do
+        let(:snippet) { create(:personal_snippet, file_name: 'test.ipynb') }
 
-      expect(subject)
-        .to eq '<span id="LC1" class="line" lang="ruby"><span class="k">class</span> <span class="nc">Foo</span><span class="p">;</span><span class="k">end</span></span>'
+        it 'returns rich notebook content' do
+          expect(subject.strip).to eq '<div class="file-content" data-endpoint="http://127.0.0.1:3000/snippets/'+ snippet.id.to_s + '/raw" id="js-notebook-viewer"></div>'
+        end
       end
 
-    it 'returns plain text highlighted content' do
-      snippet.file_name = 'test'
-      snippet.content = 'foo'
+      context 'with openapi format' do
+        let(:snippet) { create(:personal_snippet, file_name: 'openapi.yml') }
 
-      expect(subject).to eq '<span id="LC1" class="line" lang="plaintext">foo</span>'
+        it 'returns rich openapi content' do
+          expect(subject).to eq '<div class="file-content" data-endpoint="http://127.0.0.1:3000/snippets/'+ snippet.id.to_s + '/raw" id="js-openapi-viewer"></div>'
+        end
+      end
+
+      context 'with svg format' do
+        let(:snippet) { create(:personal_snippet, file_name: 'test.svg') }
+
+        it 'returns rich svg content' do
+          snippet.file_name = 'test.svg'
+
+          expect(subject).to eq '<div class="file-content" data-endpoint="http://127.0.0.1:3000/snippets/'+ snippet.id.to_s + '/raw" id="js-openapi-viewer"></div>'
+        end
+      end
+
+      context 'with other format' do
+        let(:snippet) { create(:personal_snippet, file_name: 'test') }
+
+        it 'does not return no rich content' do
+          expect(subject).to be_nil
+        end
+      end
     end
   end
 
@@ -55,19 +86,19 @@ describe SnippetBlobPresenter do
       expect(subject).to eq '<span id="LC1" class="line" lang="markdown"><span class="ge">*foo*</span></span>'
     end
 
-    it 'returns plain syntax content' do
+    it 'returns highlighted syntax content' do
       snippet.file_name = 'test.rb'
       snippet.content = 'class Foo;end'
 
       expect(subject)
-        .to eq '<span id="LC1" class="line" lang="">class Foo;end</span>'
+        .to eq '<span id="LC1" class="line" lang="ruby"><span class="k">class</span> <span class="nc">Foo</span><span class="p">;</span><span class="k">end</span></span>'
     end
 
     it 'returns plain text highlighted content' do
       snippet.file_name = 'test'
       snippet.content = 'foo'
 
-      expect(subject).to eq '<span id="LC1" class="line" lang="">foo</span>'
+      expect(subject).to eq '<span id="LC1" class="line" lang="plaintext">foo</span>'
     end
   end