Add helper methods to redirect legacy paths

3 files changed, 27 insertions, 0 deletions

diff --git a/changelogs/unreleased/bvl-free-paths.yml b/changelogs/unreleased/bvl-free-paths.yml
new file mode 100644
index 00000000000..f15459cc788
--- /dev/null
+++ b/changelogs/unreleased/bvl-free-paths.yml
@@ -0,0 +1,5 @@
+---
+title: Free up some reserved group names
+merge_request: 15052
+author:
+type: other
diff --git a/lib/gitlab/routing.rb b/lib/gitlab/routing.rb
index e57890f1143..abfd413b7ea 100644
--- a/lib/gitlab/routing.rb
+++ b/lib/gitlab/routing.rb
@@ -40,5 +40,14 @@ module Gitlab
     def self.url_helpers
       @url_helpers ||= Gitlab::Application.routes.url_helpers
     end
+
+    def self.redirect_legacy_paths(router, *paths)
+      paths.each do |path|
+        router.match "/#{path}(/*rest)",
+                     via: [:get, :post, :patch, :delete],
+                     to: router.redirect { |_params, request| request.fullpath.gsub(%r{/#{path}/*}, "/-/#{path}/") },
+                     as: "legacy_#{path}_redirect"
+      end
+    end
   end
 end
diff --git a/spec/support/legacy_path_redirect_shared_examples.rb b/spec/support/legacy_path_redirect_shared_examples.rb
new file mode 100644
index 00000000000..f300bdd48b1
--- /dev/null
+++ b/spec/support/legacy_path_redirect_shared_examples.rb
@@ -0,0 +1,13 @@
+shared_examples 'redirecting a legacy path' do |source, target|
+  include RSpec::Rails::RequestExampleGroup
+
+  it "redirects #{source} to #{target} when the resource does not exist" do
+    expect(get(source)).to redirect_to(target)
+  end
+
+  it "does not redirect #{source} to #{target} when the resource exists" do
+    resource
+
+    expect(get(source)).not_to redirect_to(target)
+  end
+end