Modify namespace name and path validation

Currently namespace name and path have uniq validaiton which does not
allow us to use same group name/path inside different groups. This
commit changes validation in next way:

* Allow same namespace name with different parent_id
* Allow same namespace path. Uniq validation should be handled by routes table

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/db/migrate/20161206153749_remove_uniq_path_index_from_namespace.rb b/db/migrate/20161206153749_remove_uniq_path_index_from_namespace.rb
new file mode 100644
index 00000000000..2977917f2d1
--- /dev/null
+++ b/db/migrate/20161206153749_remove_uniq_path_index_from_namespace.rb
@@ -0,0 +1,36 @@
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class RemoveUniqPathIndexFromNamespace < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  disable_ddl_transaction!
+
+  DOWNTIME = false
+
+  def up
+    constraint_name = 'namespaces_path_key'
+
+    transaction do
+      if index_exists?(:namespaces, :path)
+        remove_index(:namespaces, :path)
+      end
+
+      # In some bizarre cases PostgreSQL might have a separate unique constraint
+      # that we'll need to drop.
+      if constraint_exists?(constraint_name) && Gitlab::Database.postgresql?
+        execute("ALTER TABLE namespaces DROP CONSTRAINT IF EXISTS #{constraint_name};")
+      end
+    end
+  end
+
+  def down
+    unless index_exists?(:namespaces, :path)
+      add_concurrent_index(:namespaces, :path, unique: true)
+    end
+  end
+
+  def constraint_exists?(name)
+    indexes(:namespaces).map(&:name).include?(name)
+  end
+end