Fix POST /internal/allowed to cope with gitlab-shell v4.0.0 project paths

gitlab-shell v3.6.6 would give project paths like so:

* namespace/project

gitlab-shell v4.0.0 can give project paths like so:

* /namespace1/namespace2/project
* /namespace/project
* /path/to/repository/storage/namespace1/namespace2/project
* /path/to/repository/storage/namespace/project

1 files changed, 57 insertions, 0 deletions

diff --git a/lib/api/helpers/internal_helpers.rb b/lib/api/helpers/internal_helpers.rb
new file mode 100644
index 00000000000..eb223c1101d
--- /dev/null
+++ b/lib/api/helpers/internal_helpers.rb
@@ -0,0 +1,57 @@
+module API
+  module Helpers
+    module InternalHelpers
+      # Project paths may be any of the following:
+      #   * /repository/storage/path/namespace/project
+      #   * /namespace/project
+      #   * namespace/project
+      #
+      # In addition, they may have a '.git' extension and multiple namespaces
+      #
+      # Transform all these cases to 'namespace/project'
+      def clean_project_path(project_path, storage_paths = Repository.storages.values)
+        project_path = project_path.sub(/\.git\z/, '')
+
+        storage_paths.each do |storage_path|
+          storage_path = File.expand_path(storage_path)
+
+          if project_path.start_with?(storage_path)
+            project_path = project_path.sub(storage_path, '')
+            break
+          end
+        end
+
+        project_path.sub(/\A\//, '')
+      end
+
+      def project_path
+        @project_path ||= clean_project_path(params[:project])
+      end
+
+      def wiki?
+        @wiki ||= project_path.end_with?('.wiki') &&
+          !Project.find_with_namespace(project_path)
+      end
+
+      def project
+        @project ||= begin
+          # Check for *.wiki repositories.
+          # Strip out the .wiki from the pathname before finding the
+          # project. This applies the correct project permissions to
+          # the wiki repository as well.
+          project_path.chomp!('.wiki') if wiki?
+
+          Project.find_with_namespace(project_path)
+        end
+      end
+
+      def ssh_authentication_abilities
+        [
+          :read_project,
+          :download_code,
+          :push_code
+        ]
+      end
+    end
+  end
+end