Expose blob plain data in GraphQL

This is required for the repository viewer to GraphQL work

Changelog: added

app/graphql/types/repository/blob_type.rb

@@ -67,6 +67,11 @@ module Types
             description: 'Blob content rich viewer.',
             null: true
 
+      field :plain_data, GraphQL::STRING_TYPE,
+            description: 'Blob plain highlighted data.',
+            null: true,
+            calls_gitaly: true
+
       def raw_text_blob
         object.data unless object.binary?
       end

app/presenters/blob_presenter.rb

@@ -14,6 +14,12 @@ class BlobPresenter < Gitlab::View::Presenter::Delegated
     )
   end
 
+  def plain_data
+    return if blob.binary?
+
+    highlight(plain: false)
+  end
+
   def web_url
     url_helpers.project_blob_url(project, ref_qualified_path)
   end

app/presenters/snippet_blob_presenter.rb

@@ -9,12 +9,6 @@ class SnippetBlobPresenter < BlobPresenter
     render_rich_partial
   end
 
-  def plain_data
-    return if blob.binary?
-
-    highlight(plain: false)
-  end
-
   def raw_path
     snippet_blob_raw_route(only_path: true)
   end

changelogs/unreleased/323195-add-blob-plain-data-attribute.yml

+---
+title: Expose blob plain data in GraphQL
+merge_request: 61016
+author:
+type: added

doc/api/graphql/reference/index.md

@@ -11744,6 +11744,7 @@ Returns [`Tree`](#tree).
 | <a id="repositoryblobname"></a>`name` | [`String`](#string) | Blob name. |
 | <a id="repositorybloboid"></a>`oid` | [`String!`](#string) | OID of the blob. |
 | <a id="repositoryblobpath"></a>`path` | [`String!`](#string) | Path of the blob. |
+| <a id="repositoryblobplaindata"></a>`plainData` | [`String`](#string) | Blob plain highlighted data. |
 | <a id="repositoryblobrawblob"></a>`rawBlob` | [`String`](#string) | The raw content of the blob. |
 | <a id="repositoryblobrawpath"></a>`rawPath` | [`String`](#string) | Web path to download the raw blob. |
 | <a id="repositoryblobrawsize"></a>`rawSize` | [`Int`](#int) | Size (in bytes) of the blob, or the blob target if stored externally. |

spec/graphql/types/repository/blob_type_spec.rb

@@ -24,7 +24,8 @@ RSpec.describe Types::Repository::BlobType do
       :raw_path,
       :replace_path,
       :simple_viewer,
-      :rich_viewer
+      :rich_viewer,
+      :plain_data
     )
   end
 end

spec/presenters/blob_presenter_spec.rb

@@ -83,4 +83,43 @@ RSpec.describe BlobPresenter do
       end
     end
   end
+
+  describe '#plain_data' do
+    let(:blob) { repository.blob_at('HEAD', file) }
+
+    subject { described_class.new(blob).plain_data }
+
+    context 'when blob is binary' do
+      let(:file) { 'files/images/logo-black.png' }
+
+      it 'returns nil' do
+        expect(subject).to be_nil
+      end
+    end
+
+    context 'when blob is markup' do
+      let(:file) { 'README.md' }
+
+      it 'returns plain content' do
+        expect(subject).to include('<span id="LC1" class="line" lang="markdown">')
+      end
+    end
+
+    context 'when blob has syntax' do
+      let(:file) { 'files/ruby/regex.rb' }
+
+      it 'returns highlighted syntax content' do
+        expect(subject)
+          .to include '<span id="LC1" class="line" lang="ruby"><span class="k">module</span> <span class="nn">Gitlab</span>'
+      end
+    end
+
+    context 'when blob has plain data' do
+      let(:file) { 'LICENSE' }
+
+      it 'returns plain text highlighted content' do
+        expect(subject).to include('<span id="LC1" class="line" lang="plaintext">The MIT License (MIT)</span>')
+      end
+    end
+  end
 end

spec/presenters/snippet_blob_presenter_spec.rb

@@ -80,45 +80,6 @@ RSpec.describe SnippetBlobPresenter do
     end
   end
 
-  describe '#plain_data' do
-    let(:blob) { blob_at(file) }
-
-    subject { described_class.new(blob).plain_data }
-
-    context 'when blob is binary' do
-      let(:file) { 'files/images/logo-black.png' }
-
-      it 'returns nil' do
-        expect(subject).to be_nil
-      end
-    end
-
-    context 'when blob is markup' do
-      let(:file) { 'README.md' }
-
-      it 'returns plain content' do
-        expect(subject).to include('<span id="LC1" class="line" lang="markdown">')
-      end
-    end
-
-    context 'when blob has syntax' do
-      let(:file) { 'files/ruby/regex.rb' }
-
-      it 'returns highlighted syntax content' do
-        expect(subject)
-          .to include '<span id="LC1" class="line" lang="ruby"><span class="k">module</span> <span class="nn">Gitlab</span>'
-      end
-    end
-
-    context 'when blob has plain data' do
-      let(:file) { 'LICENSE' }
-
-      it 'returns plain text highlighted content' do
-        expect(subject).to include('<span id="LC1" class="line" lang="plaintext">The MIT License (MIT)</span>')
-      end
-    end
-  end
-
   describe 'route helpers' do
     let_it_be(:project)          { create(:project) }
     let_it_be(:user)             { create(:user) }