Backend for HTML serving with GitLab Pages

app/helpers/artifact_helper.rb

+module ArtifactHelper
+  include GitlabRoutingHelper
+
+  def link_to_artifact(project, job, file)
+    if external_url?(file.blob)
+      html_artifact_url(project, job, file.blob)
+    else
+      file_project_job_artifacts_path(project, job, path: file.path)
+    end
+  end
+
+  def external_url?(blob)
+    blob.name.end_with?(".html") &&
+      pages_config.enabled &&
+      pages_config.artifacts_server
+  end
+
+  private
+
+  def html_artifact_url(project, job, blob)
+    http = pages_config.https ? "https://" : "http://"
+    domain = "#{project.namespace.to_param}.#{pages_config.host}/"
+    path = "-/jobs/#{job.id}/artifacts/#{blob.path}"
+
+    http + domain + path
+  end
+
+  def pages_config
+    Gitlab.config.pages
+  end
+end

app/views/projects/artifacts/_tree_file.html.haml

-- todo_external_artifacts_path = 'https://google.com'
-- is_external_link = !todo_external_artifacts_path.blank?
-- path_to_file = todo_external_artifacts_path || file_project_job_artifacts_path(@project, @build, path: file.path)
+- blob = file.blob
+- is_external_link = external_link?(blob)
+- path_to_file = link_to_artifact(@project, @build, file)
 %tr.tree-item.js-artifact-tree-row{ data: { link: path_to_file, external_link: "#{is_external_link}" } }
-  - blob = file.blob
   %td.tree-item-file-name
     = tree_icon('file', blob.mode, blob.name)
     = link_to path_to_file,

config/gitlab.yml.example

@@ -164,6 +164,7 @@ production: &base
     host: example.com
     port: 80 # Set to 443 if you serve the pages with HTTPS
     https: false # Set to true if you serve the pages with HTTPS
+    artifacts_server: true
     # external_http: ["1.1.1.1:80", "[2001::1]:80"] # If defined, enables custom domain support in GitLab Pages
     # external_https: ["1.1.1.1:443", "[2001::1]:443"] # If defined, enables custom domain and certificate support in GitLab Pages

spec/helpers/artifact_helper_spec.rb

+require 'spec_helper'
+
+describe ArtifactHelper do
+  set(:job) { create(:ci_build, :artifacts) }
+
+  let(:html_entry) { job.artifacts_metadata_entry("other_artifacts_0.1.2/index.html") }
+  let(:txt_entry) { job.artifacts_metadata_entry("other_artifacts_0.1.2/doc_sample.txt") }
+
+  before do
+    allow(Gitlab.config.pages).to receive(:enabled).and_return(true)
+    allow(Gitlab.config.pages).to receive(:artifacts_server).and_return(true)
+  end
+
+  describe '#link_to_artifact' do
+    context 'link_to_pages returns true' do
+      subject { link_to_artifact(job.project, job, entry) }
+
+      before do
+        allow(Gitlab.config.pages).to receive(:enabled).and_return(true)
+      end
+
+      context 'when the entry is HTML' do
+        let(:entry) { html_entry }
+
+        it { is_expected.to match Gitlab.config.pages.host }
+        it { is_expected.to match /-\/jobs\/\d+\/artifacts/ }
+      end
+
+      context 'when the entry is not HTML' do
+        let(:entry) { txt_entry }
+
+        it { is_expected.not_to match Gitlab.config.pages.host }
+      end
+    end
+  end
+
+  describe '#external_url?' do
+    context 'pages enabled' do
+      before do
+        allow(Gitlab.config.pages).to receive(:artifacts_server).and_return(true)
+      end
+
+      it 'returns true for HTML files' do
+        expect(external_url?(txt_entry.blob)).to be(false)
+      end
+
+      it 'returns true for HTML files' do
+        expect(external_url?(html_entry.blob)).to be(true)
+      end
+    end
+  end
+end