Merge branch 'zj-load-languages-from-database' into 'master'

Load repository language from the DB if detected

Closes #47390

See merge request gitlab-org/gitlab-ce!25518

app/controllers/projects/graphs_controller.rb

@@ -45,7 +45,14 @@ class Projects::GraphsController < Projects::ApplicationController
   end
 
   def get_languages
-    @languages = @project.repository.languages
+    @languages =
+      if @project.repository_languages.present?
+        @project.repository_languages.map do |lang|
+          { value: lang.share, label: lang.name, color: lang.color, highlight: lang.color }
+        end
+      else
+        @project.repository.languages
+      end
   end
 
   def fetch_graph

changelogs/unreleased/zj-load-languages-from-database.yml

+---
+title: Load repository language from the database if detected before
+merge_request: 25518
+author:
+type: performance

lib/api/projects.rb

@@ -388,8 +388,12 @@ module API
 
       desc 'Get languages in project repository'
       get ':id/languages' do
+        if user_project.repository_languages.present?
+          user_project.repository_languages.map { |l| [l.name, l.share] }.to_h
+        else
           user_project.repository.languages.map { |language| language.values_at(:label, :value) }.to_h
         end
+      end
 
       desc 'Remove a project'
       delete ":id" do

spec/controllers/projects/graphs_controller_spec.rb

@@ -24,4 +24,20 @@ describe Projects::GraphsController do
       expect(response).to redirect_to action: :charts
     end
   end
+
+  describe 'charts' do
+    context 'when languages were previously detected' do
+      let!(:repository_language) { create(:repository_language, project: project) }
+
+      it 'sets the languages properly' do
+        get(:charts, params: { namespace_id: project.namespace.path, project_id: project.path, id: 'master' })
+
+        expect(assigns[:languages]).to eq(
+          [value: repository_language.share,
+           label: repository_language.name,
+           color: repository_language.color,
+           highlight: repository_language.color])
+      end
+    end
+  end
 end

spec/requests/api/projects_spec.rb

@@ -4,6 +4,15 @@ require 'spec_helper'
 shared_examples 'languages and percentages JSON response' do
   let(:expected_languages) { project.repository.languages.map { |language| language.values_at(:label, :value)}.to_h }
 
+  before do
+    allow(project.repository).to receive(:languages).and_return(
+      [{ value: 66.69, label: "Ruby", color: "#701516", highlight: "#701516" },
+       { value: 22.98, label: "JavaScript", color: "#f1e05a", highlight: "#f1e05a" },
+       { value: 7.91, label: "HTML", color: "#e34c26", highlight: "#e34c26" },
+       { value: 2.42, label: "CoffeeScript", color: "#244776", highlight: "#244776" }]
+    )
+  end
+
   it 'returns expected language values' do
     get api("/projects/#{project.id}/languages", user)
 
@@ -11,6 +20,23 @@ shared_examples 'languages and percentages JSON response' do
     expect(json_response).to eq(expected_languages)
     expect(json_response.count).to be > 1
   end
+
+  context 'when the languages were detected before' do
+    before do
+      Projects::DetectRepositoryLanguagesService.new(project, project.owner).execute
+    end
+
+    it 'returns the detection from the database' do
+      # Allow this to happen once, so the expected languages can be determined
+      expect(project.repository).to receive(:languages).once
+
+      get api("/projects/#{project.id}/languages", user)
+
+      expect(response).to have_gitlab_http_status(:ok)
+      expect(json_response).to eq(expected_languages)
+      expect(json_response.count).to be > 1
+    end
+  end
 end
 
 describe API::Projects do