1 files changed, 101 insertions, 6 deletions

diff --git a/app/models/concerns/routable.rb b/app/models/concerns/routable.rb
index 529fb5ce988..c4463abdfe6 100644
--- a/app/models/concerns/routable.rb
+++ b/app/models/concerns/routable.rb
@@ -5,6 +5,7 @@ module Routable
 
   included do
     has_one :route, as: :source, autosave: true, dependent: :destroy
+    has_many :redirect_routes, as: :source, autosave: true, dependent: :destroy
 
     validates_associated :route
     validates :route, presence: true
@@ -26,16 +27,31 @@ module Routable
     #     Klass.find_by_full_path('gitlab-org/gitlab-ce')
     #
     # Returns a single object, or nil.
-    def find_by_full_path(path)
+    def find_by_full_path(path, follow_redirects: false)
       # On MySQL we want to ensure the ORDER BY uses a case-sensitive match so
       # any literal matches come first, for this we have to use "BINARY".
       # Without this there's still no guarantee in what order MySQL will return
       # rows.
+      #
+      # Why do we do this?
+      #
+      # Even though we have Rails validation on Route for unique paths
+      # (case-insensitive), there are old projects in our DB (and possibly
+      # clients' DBs) that have the same path with different cases.
+      # See https://gitlab.com/gitlab-org/gitlab-ce/issues/18603. Also note that
+      # our unique index is case-sensitive in Postgres.
       binary = Gitlab::Database.mysql? ? 'BINARY' : ''
-
       order_sql = "(CASE WHEN #{binary} routes.path = #{connection.quote(path)} THEN 0 ELSE 1 END)"
-
-      where_full_path_in([path]).reorder(order_sql).take
+      found = where_full_path_in([path]).reorder(order_sql).take
+      return found if found
+
+      if follow_redirects
+        if Gitlab::Database.postgresql?
+          joins(:redirect_routes).find_by("LOWER(redirect_routes.path) = LOWER(?)", path)
+        else
+          joins(:redirect_routes).find_by(redirect_routes: { path: path })
+        end
+      end
     end
 
     # Builds a relation to find multiple objects by their full paths.
@@ -83,6 +99,74 @@ module Routable
                AND members.source_type = r2.source_type").
         where('members.user_id = ?', user_id)
     end
+
+    # Builds a relation to find multiple objects that are nested under user
+    # membership. Includes the parent, as opposed to `#member_descendants`
+    # which only includes the descendants.
+    #
+    # Usage:
+    #
+    #     Klass.member_self_and_descendants(1)
+    #
+    # Returns an ActiveRecord::Relation.
+    def member_self_and_descendants(user_id)
+      joins(:route).
+        joins("INNER JOIN routes r2 ON routes.path LIKE CONCAT(r2.path, '/%')
+               OR routes.path = r2.path
+               INNER JOIN members ON members.source_id = r2.source_id
+               AND members.source_type = r2.source_type").
+        where('members.user_id = ?', user_id)
+    end
+
+    # Returns all objects in a hierarchy, where any node in the hierarchy is
+    # under the user membership.
+    #
+    # Usage:
+    #
+    #     Klass.member_hierarchy(1)
+    #
+    # Examples:
+    #
+    #     Given the following group tree...
+    #
+    #            _______group_1_______
+    #           |                     |
+    #           |                     |
+    #     nested_group_1        nested_group_2
+    #           |                     |
+    #           |                     |
+    #     nested_group_1_1      nested_group_2_1
+    #
+    #
+    #     ... the following results are returned:
+    #
+    #     * the user is a member of group 1
+    #       => 'group_1',
+    #          'nested_group_1', nested_group_1_1',
+    #          'nested_group_2', 'nested_group_2_1'
+    #
+    #     * the user is a member of nested_group_2
+    #       => 'group1',
+    #          'nested_group_2', 'nested_group_2_1'
+    #
+    #     * the user is a member of nested_group_2_1
+    #       => 'group1',
+    #          'nested_group_2', 'nested_group_2_1'
+    #
+    # Returns an ActiveRecord::Relation.
+    def member_hierarchy(user_id)
+      paths = member_self_and_descendants(user_id).pluck('routes.path')
+
+      return none if paths.empty?
+
+      wheres = paths.map do |path|
+        "#{connection.quote(path)} = routes.path
+         OR
+         #{connection.quote(path)} LIKE CONCAT(routes.path, '/%')"
+      end
+
+      joins(:route).where(wheres.join(' OR '))
+    end
   end
 
   def full_name
@@ -95,7 +179,20 @@ module Routable
     end
   end
 
+  # Every time `project.namespace.becomes(Namespace)` is called for polymorphic_path,
+  # a new instance is instantiated, and we end up duplicating the same query to retrieve
+  # the route. Caching this per request ensures that even if we have multiple instances,
+  # we will not have to duplicate work, avoiding N+1 queries in some cases.
   def full_path
+    return uncached_full_path unless RequestStore.active?
+
+    key = "routable/full_path/#{self.class.name}/#{self.id}"
+    RequestStore[key] ||= uncached_full_path
+  end
+
+  private
+
+  def uncached_full_path
     if route && route.path.present?
       @full_path ||= route.path
     else
@@ -105,8 +202,6 @@ module Routable
     end
   end
 
-  private
-
   def full_name_changed?
     name_changed? || parent_changed?
   end