1 files changed, 35 insertions, 0 deletions
diff --git a/app/models/trending_project.rb b/app/models/trending_project.rb
new file mode 100644
index 00000000000..27e3732da17
--- /dev/null
+++ b/app/models/trending_project.rb
@@ -0,0 +1,35 @@
+class TrendingProject < ActiveRecord::Base
+  belongs_to :project
+
+  # The number of months to include in the trending calculation.
+  MONTHS_TO_INCLUDE = 1
+
+  # The maximum number of projects to include in the trending set.
+  PROJECTS_LIMIT = 100
+
+  # Populates the trending projects table with the current list of trending
+  # projects.
+  def self.refresh!
+    # The calculation **must** run in a transaction. If the removal of data and
+    # insertion of new data were to run separately a user might end up with an
+    # empty list of trending projects for a short period of time.
+    transaction do
+      delete_all
+
+      timestamp = connection.quote(MONTHS_TO_INCLUDE.months.ago)
+
+      connection.execute <<-EOF.strip_heredoc
+        INSERT INTO #{table_name} (project_id)
+        SELECT project_id
+        FROM notes
+        INNER JOIN projects ON projects.id = notes.project_id
+        WHERE notes.created_at >= #{timestamp}
+        AND notes.system IS FALSE
+        AND projects.visibility_level = #{Gitlab::VisibilityLevel::PUBLIC}
+        GROUP BY project_id
+        ORDER BY count(*) DESC
+        LIMIT #{PROJECTS_LIMIT};
+      EOF
+    end
+  end
+end