Merge branch 'fix-access-to-pipelines-for-anonymous' into 'master'

Allow anonymous user to access pipelines

## What does this MR do?

It fixes an issue where the Pipelines is shown for the Anonymous users,
but they get 404 when clicked. Their session is then logged out.

Fixes #17717.

See merge request !4233

CHANGELOG

@@ -2,6 +2,7 @@ Please view this file on the master branch, on stable branches it's out of date.
 v 8.8.1
   - Add documentation for the "Health Check" feature
+  - Allow anonymous users to access a public project's pipelines
   - Fix MySQL compatibility in zero downtime migrations helpers
   - Fix the CI login to Container Registry (the gitlab-ci-token user)

app/helpers/projects_helper.rb

@@ -144,6 +144,10 @@ module ProjectsHelper
       nav_tabs << :merge_requests
     end
+    if can?(current_user, :read_pipeline, project)
+      nav_tabs << :pipelines
+    end
+
     if can?(current_user, :read_build, project)
       nav_tabs << :builds
     end

app/models/ability.rb

@@ -60,6 +60,7 @@ class Ability
           :read_project_member,
           :read_merge_request,
           :read_note,
+          :read_pipeline,
           :read_commit_status,
           :read_container_image,
           :download_code

app/views/layouts/nav/_project.html.haml

@@ -38,7 +38,7 @@
         %span
           Commits
-  - if project_nav_tab? :builds
+  - if project_nav_tab? :pipelines
     = nav_link(controller: :pipelines) do
       = link_to project_pipelines_path(@project), title: 'Pipelines', class: 'shortcuts-pipelines' do
         = icon('ship fw')
@@ -46,6 +46,7 @@
           Pipelines
           %span.count.ci_counter= number_with_delimiter(@project.ci_commits.running_or_pending.count)
+  - if project_nav_tab? :builds
     = nav_link(controller: %w(builds)) do
       = link_to project_builds_path(@project), title: 'Builds', class: 'shortcuts-builds' do
         = icon('cubes fw')

spec/features/pipelines_spec.rb

@@ -24,6 +24,12 @@ describe "Pipelines" do
       end
     end
+    context 'anonymous access' do
+      before { visit namespace_project_pipelines_path(project.namespace, project) }
+
+      it { expect(page).to have_http_status(:success) }
+    end
+
     context 'cancelable pipeline' do
       let!(:running) { create(:ci_build, :running, commit: pipeline, stage: 'test', commands: 'test') }