Merge branch 'sh-optimize-projects-api' into 'master'

Optimize /api/v4/projects endpoint for visibility level

See merge request gitlab-org/gitlab-ce!26481

2 files changed, 36 insertions, 9 deletions

diff --git a/app/finders/projects_finder.rb b/app/finders/projects_finder.rb
index 93d3c991846..0319e95d439 100644
--- a/app/finders/projects_finder.rb
+++ b/app/finders/projects_finder.rb
@@ -81,7 +81,7 @@ class ProjectsFinder < UnionFinder
       if private_only?
         current_user.authorized_projects
       else
-        Project.public_or_visible_to_user(current_user)
+        Project.public_or_visible_to_user(current_user, params[:visibility_level])
       end
     end
   end
diff --git a/app/models/project.rb b/app/models/project.rb
index 97a17d120c6..06010409574 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -459,14 +459,41 @@ class Project < ActiveRecord::Base
 
   # Returns a collection of projects that is either public or visible to the
   # logged in user.
-  def self.public_or_visible_to_user(user = nil)
-    if user
-      where('EXISTS (?) OR projects.visibility_level IN (?)',
-            user.authorizations_for_projects,
-            Gitlab::VisibilityLevel.levels_for_user(user))
-    else
-      public_to_user
-    end
+  #
+  # requested_visiblity_levels: Normally all projects that are visible
+  # to the user (e.g. internal and public) are queried, but this
+  # parameter allows the caller to narrow the search space to optimize
+  # database queries. For instance, a caller may only want to see
+  # internal projects. Instead of querying for internal and public
+  # projects and throwing away public projects, this parameter allows
+  # the query to be targeted for only internal projects.
+  def self.public_or_visible_to_user(user = nil, requested_visibility_levels = [])
+    return public_to_user unless user
+
+    visible_levels = Gitlab::VisibilityLevel.levels_for_user(user)
+    include_private = true
+    requested_visibility_levels = Array(requested_visibility_levels)
+
+    if requested_visibility_levels.present?
+      visible_levels &= requested_visibility_levels
+      include_private = requested_visibility_levels.include?(Gitlab::VisibilityLevel::PRIVATE)
+    end
+
+    public_or_internal_rel =
+      if visible_levels.present?
+        where('projects.visibility_level IN (?)', visible_levels)
+      else
+        Project.none
+      end
+
+    private_rel =
+      if include_private
+        where('EXISTS (?)', user.authorizations_for_projects)
+      else
+        Project.none
+      end
+
+    public_or_internal_rel.or(private_rel)
   end
 
   # project features may be "disabled", "internal", "enabled" or "public". If "internal",