Add more storage statistics

This adds counters for build artifacts and LFS objects, and moves
the preexisting repository_size and commit_count from the projects
table into a new project_statistics table.

The counters are displayed in the administration area for projects
and groups, and also available through the API for admins (on */all)
and normal users (on */owned)

The statistics are updated through ProjectCacheWorker, which can now
do more granular updates with the new :statistics argument.

1 files changed, 43 insertions, 0 deletions

diff --git a/app/models/project_statistics.rb b/app/models/project_statistics.rb
new file mode 100644
index 00000000000..2270ac75071
--- /dev/null
+++ b/app/models/project_statistics.rb
@@ -0,0 +1,43 @@
+class ProjectStatistics < ActiveRecord::Base
+  belongs_to :project
+  belongs_to :namespace
+
+  before_save :update_storage_size
+
+  STORAGE_COLUMNS = [:repository_size, :lfs_objects_size, :build_artifacts_size]
+  STATISTICS_COLUMNS = [:commit_count] + STORAGE_COLUMNS
+
+  def total_repository_size
+    repository_size + lfs_objects_size
+  end
+
+  def refresh!(only: nil)
+    STATISTICS_COLUMNS.each do |column, generator|
+      if only.blank? || only.include?(column)
+        public_send("update_#{column}")
+      end
+    end
+
+    save!
+  end
+
+  def update_commit_count
+    self.commit_count = project.repository.commit_count
+  end
+
+  def update_repository_size
+    self.repository_size = project.repository.size
+  end
+
+  def update_lfs_objects_size
+    self.lfs_objects_size = project.lfs_objects.sum(:size)
+  end
+
+  def update_build_artifacts_size
+    self.build_artifacts_size = project.builds.sum(:artifacts_size)
+  end
+
+  def update_storage_size
+    self.storage_size = STORAGE_COLUMNS.sum(&method(:read_attribute))
+  end
+end