Redirect project.wiki.git to project wiki home

https://gitlab.com/gitlab-org/gitlab-ce/issues/19186

changelogs/unreleased/19186-redirect-wiki-git-route-to-wiki.yml

+---
+title: Redirect from a project wiki git route to the project wiki home
+merge_request: 31085
+author:
+type: added

config/routes/git_http.rb

@@ -34,6 +34,18 @@ scope(path: '*namespace_id/:project_id',
     end
   end
+  # Redirect /group/project.wiki.git to the project wiki
+  scope(format: true, constraints: { project_id: Gitlab::PathRegex.project_wiki_git_route_regex, format: :git }) do
+    wiki_redirect = redirect do |params, request|
+      project_id = params[:project_id].delete_suffix('.wiki')
+      path = [params[:namespace_id], project_id, 'wikis'].join('/')
+      path << "?#{request.query_string}" unless request.query_string.blank?
+      path
+    end
+
+    get '/', to: wiki_redirect
+  end
+
   # Redirect /group/project/info/refs to /group/project.git/info/refs
   scope(constraints: { project_id: Gitlab::PathRegex.project_route_regex }) do
     # Allow /info/refs, /info/refs?service=git-upload-pack, and

lib/gitlab/path_regex.rb

@@ -175,6 +175,10 @@ module Gitlab
       @project_git_route_regex ||= /#{project_route_regex}\.git/.freeze
     end
+    def project_wiki_git_route_regex
+      @project_wiki_git_route_regex ||= /#{PATH_REGEX_STR}\.wiki/.freeze
+    end
+
     def full_namespace_path_regex
       @full_namespace_path_regex ||= %r{\A#{full_namespace_route_regex}/\z}
     end

spec/routing/git_http_routing_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe 'git_http routing' do
+  include RSpec::Rails::RequestExampleGroup
+
+  describe 'wiki.git routing', 'routing' do
+    let(:wiki_path)  { '/gitlab/gitlabhq/wikis' }
+
+    it 'redirects namespace/project.wiki.git to the project wiki' do
+      expect(get('/gitlab/gitlabhq.wiki.git')).to redirect_to(wiki_path)
+    end
+
+    it 'preserves query parameters' do
+      expect(get('/gitlab/gitlabhq.wiki.git?foo=bar&baz=qux')).to redirect_to("#{wiki_path}?foo=bar&baz=qux")
+    end
+
+    it 'only redirects when the format is .git' do
+      expect(get('/gitlab/gitlabhq.wiki')).not_to redirect_to(wiki_path)
+      expect(get('/gitlab/gitlabhq.wiki.json')).not_to redirect_to(wiki_path)
+    end
+  end
+end