Add data migration for productivity analytics

ee/lib/gitlab/background_migration/recalculate_productivity_analytics.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module BackgroundMigration
+    # Execution time estimates: 55 records per second,
+    # with 3 month period it will be 3.2mln records affected
+    # and with 320 batches it will be ~16h total execution time
+    class RecalculateProductivityAnalytics
+      BATCH_SIZE = 1_000
+
+      METRICS_TO_CALCULATE = %w[first_comment_at first_commit_at last_commit_at diff_size commits_count modified_paths_size].freeze
+
+      module Migratable
+        class Metrics < ActiveRecord::Base
+          include EachBatch
+
+          belongs_to :merge_request, class_name: 'Migratable::MergeRequest', foreign_key: :merge_request_id, inverse_of: :metrics
+
+          self.table_name = 'merge_request_metrics'
+        end
+
+        class MergeRequest < ActiveRecord::Base
+          self.table_name = 'merge_requests'
+
+          has_many :diffs, class_name: 'Migratable::MergeRequestDiff', foreign_key: :merge_request_id
+
+          has_many :user_notes, -> { where(noteable_type: 'MergeRequest').where.not(author_id: User.bots) }, class_name: 'Migratable::Note', foreign_key: :noteable_id
+
+          has_one :metrics, class_name: 'Migratable::Metrics', foreign_key: :merge_request_id, inverse_of: :merge_request
+
+          attr_writer :diff, :first_user_note
+
+          def first_user_note
+            @first_user_note ||= user_notes.order(created_at: :asc).first
+          end
+
+          def diff
+            @diff ||= diffs.order(id: :desc).includes(:files).first # max_by(&:id)
+          end
+        end
+
+        class Note < ActiveRecord::Base
+          self.table_name = 'notes'
+        end
+
+        class User < ActiveRecord::Base
+          self.table_name = 'users'
+
+          def self.bots
+            @bots ||= where.not(bot_type: nil).select(:id).to_a
+          end
+        end
+
+        class MergeRequestDiff < ActiveRecord::Base
+          self.table_name = 'merge_request_diffs'
+
+          has_many :commits, class_name: 'Migratable::MergeRequestDiffCommit', foreign_key: :merge_request_diff_id
+          has_many :files, class_name: 'Migratable::MergeRequestDiffFile', foreign_key: :merge_request_diff_id
+
+          attr_writer :first_commit, :last_commit
+
+          def first_commit
+            @first_commit ||= commits.order(relative_order: :desc).first
+          end
+
+          def last_commit
+            @last_commit ||= commits.order(relative_order: :desc).last
+          end
+
+          def lines_count
+            @lines_count ||= Gitlab::Git::DiffCollection.new(files.map(&:to_hash), limits: false).sum(&:line_count)
+          end
+
+          def modified_paths
+            @modified_paths ||= files.map { |f| [f.new_path, f.old_path] }.flatten.uniq
+          end
+        end
+
+        class MergeRequestDiffCommit < ActiveRecord::Base
+          self.table_name = 'merge_request_diff_commits'
+        end
+
+        class MergeRequestDiffFile < ActiveRecord::Base
+          include DiffFile
+
+          self.table_name = 'merge_request_diff_files'
+        end
+      end
+
+      def perform(start_id, end_id)
+        Migratable::Metrics.where("merged_at > ? ", 3.months.ago - 1.day)
+          .where(id: start_id...end_id).each_batch(of: BATCH_SIZE) do |batch|
+          ActiveRecord::Base.transaction do
+            preload(batch).each do |merge_request_metrics|
+              update_merge_request_metrics(merge_request_metrics)
+            end
+          end
+        end
+      end
+
+      private
+
+      def update_merge_request_metrics(metrics)
+        merge_request = metrics.merge_request
+        diff = merge_request.diff
+
+        return unless diff
+
+        metrics.first_comment_at = merge_request.first_user_note&.created_at
+        metrics.first_commit_at = diff.first_commit&.authored_date
+        metrics.last_commit_at = diff.last_commit&.committed_date
+        metrics.commits_count = diff.commits_count
+        metrics.diff_size = diff.lines_count
+        metrics.modified_paths_size = diff.modified_paths.size
+
+        metrics.save!
+      end
+
+      def preload(metrics_batch)
+        metrics_batch.includes(:merge_request).tap do |scope|
+          preload_diffs(scope)
+          preload_notes(scope)
+        end
+      end
+
+      def preload_notes(scope)
+        first_user_notes_ids = Migratable::Note
+          .where(noteable_id: scope.map(&:merge_request_id), noteable_type: 'MergeRequest')
+          .where.not(author_id: Migratable::User.bots).group(:noteable_id).pluck(Arel.sql('noteable_id, MIN(id)')).to_h
+
+        notes = Migratable::Note.where(id: first_user_notes_ids.values)
+
+        scope.each do |metric|
+          first_note_id = first_user_notes_ids[metric.merge_request_id]
+          metric.merge_request.first_user_note = notes.detect { |note| note.id == first_note_id}
+        end
+      end
+
+      def preload_diffs(scope)
+        last_diffs_ids = Migratable::MergeRequestDiff
+          .where(merge_request_id: scope.map(&:merge_request_id))
+          .group(:merge_request_id)
+          .pluck(Arel.sql('merge_request_id, MAX(id)')).to_h
+
+        last_diffs = Migratable::MergeRequestDiff.where(id: last_diffs_ids.values).includes(:files)
+
+        preload_commits(last_diffs)
+
+        scope.each do |metric|
+          diff_id = last_diffs_ids[metric.merge_request.id]
+          next unless diff_id
+
+          diff = last_diffs.detect { |d| d.id == diff_id }
+
+          metric.merge_request.diff = diff
+        end
+      end
+
+      def preload_commits(scope)
+        commits_map = Migratable::MergeRequestDiffCommit.where(merge_request_diff_id: scope.map(&:id))
+          .group(:merge_request_diff_id)
+          .pluck(Arel.sql('merge_request_diff_id, MIN(relative_order), MAX(relative_order)'))
+
+        commits_cond = Arel.sql(commits_map.map do |info|
+          "(merge_request_diff_id = #{info[0]} AND relative_order IN(#{info[1]}, #{info[2]}))"
+        end.join(' OR '))
+
+        commits = Migratable::MergeRequestDiffCommit.where(commits_cond)
+
+        scope.each do |diff|
+          related_commits = commits.select { |c| c.merge_request_diff_id == diff.id }
+
+          diff.first_commit = related_commits.max_by(&:relative_order)
+          diff.last_commit = related_commits.min_by(&:relative_order)
+        end
+      end
+    end
+  end
+end

ee/spec/lib/gitlab/background_migration/recalculate_productivity_analytics_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::BackgroundMigration::RecalculateProductivityAnalytics, migration: true, schema: 20190802012622 do
+  include MigrationHelpers::RecalculateProductivityAnalyticsHelpers
+
+  let(:background_migration) { described_class.new }
+
+  describe '#perform' do
+    let(:merged_at_after) { 6.weeks.ago }
+
+    subject { background_migration.perform(*id_boundaries) }
+
+    let(:id_boundaries) do
+      [merged_mr.id, open_mr.id].minmax
+    end
+
+    let(:merged_mr) { create_populated_mr(user, project, metrics: { merged_at: merged_at_after + 1.week }) }
+    let(:open_mr) { create_populated_mr(user, project) }
+
+    let(:user) do
+      table(:users).create!(
+        email: 'sample_user@user.com',
+        projects_limit: 10,
+        name: 'Test User',
+        username: 'sample_user'
+      )
+    end
+
+    let(:bot) do
+      table(:users).create!(
+        email: 'bot@bot.com',
+        projects_limit: 10,
+        name: 'Test Bot',
+        username: 'sample_bot',
+        bot_type: 1 # support bot
+      )
+    end
+
+    let(:group) { table(:namespaces).create!(path: 'test_group', name: 'test_group') }
+
+    let(:project) do
+      table(:projects).create!(name: 'test project', path: 'test_project', namespace_id: group.id, creator_id: user.id)
+    end
+
+    it 'updates productivity metrics for merged MRs' do
+      Timecop.freeze(Time.zone.now.change(nsec: 0)) do
+        merged_mr
+        expect { subject }
+          .to change {
+            table(:merge_request_metrics).find_by(merge_request_id: merged_mr.id).attributes.slice(*described_class::METRICS_TO_CALCULATE)
+          }.to({ "commits_count" => 2, "diff_size" => 20, "first_comment_at" => 4.weeks.ago + 1.day, "first_commit_at" => 4.weeks.ago, "last_commit_at" => 1.week.ago, "modified_paths_size" => 2 })
+      end
+    end
+
+    it 'does not update productivity metrics for open MR' do
+      open_mr
+      expect { subject }
+        .not_to change {
+          table(:merge_request_metrics).find_by(merge_request_id: open_mr.id).attributes.slice(*described_class::METRICS_TO_CALCULATE)
+        }
+    end
+  end
+end

ee/spec/support/migration_helpers/recalculate_productivity_analytics_helpers.rb

+# frozen_string_literal: true
+
+module MigrationHelpers
+  module RecalculateProductivityAnalyticsHelpers
+    def create_populated_mr(user, project, attributes: {}, metrics: {})
+      base = {
+        author_id: user.id,
+        source_project_id: project.id,
+        target_project_id: project.id,
+        source_branch: 'master',
+        target_branch: 'feature'
+      }
+
+      mr = table(:merge_requests).create!(base.merge(attributes))
+      table(:merge_request_metrics).create!(metrics.merge(merge_request_id: mr.id))
+
+      create_mr_activity(mr)
+      create_notes(mr)
+
+      mr
+    end
+
+    def create_notes(mr)
+      # 4 notes per MR
+      table(:notes).create!(note: 'sample note', noteable_type: 'MergeRequest', noteable_id: mr.id, author_id: user.id, created_at: 4.weeks.ago + 1.day)
+      table(:notes).create!(note: 'sample note 2', noteable_type: 'MergeRequest', noteable_id: mr.id, author_id: user.id, created_at: 4.weeks.ago + 2.days)
+      table(:notes).create!(note: 'system note', noteable_type: 'MergeRequest', noteable_id: mr.id, created_at: 4.weeks.ago + 3.days)
+      table(:notes).create!(note: 'bot note', noteable_type: 'MergeRequest', noteable_id: mr.id, author_id: bot.id, created_at: 4.weeks.ago + 2.days)
+    end
+
+    def create_mr_activity(mr)
+      diff = table(:merge_request_diffs).create!(merge_request_id: mr.id, commits_count: 2)
+
+      # 2 commits per MR
+      table(:merge_request_diff_commits).create!(sha: '456', merge_request_diff_id: diff.id, authored_date: 2.weeks.ago, committed_date: 1.week.ago, relative_order: 0)
+      table(:merge_request_diff_commits).create!(sha: '123', merge_request_diff_id: diff.id, authored_date: 4.weeks.ago, committed_date: 3.weeks.ago, relative_order: 1)
+
+      # 2 diff files per MR
+      base_diff_files_attributes = {
+        merge_request_diff_id: diff.id,
+        new_file: true,
+        renamed_file: false,
+        deleted_file: false,
+        too_large: false,
+        a_mode: '0',
+        b_mode: '160000',
+        diff: "@@ -1,6 +1,6 @@\n class Commit\n   constructor: ->\n     $('.files .diff-file').each ->\n-      new CommitFile(this)\n+      new CommitFile(@)\n \n-@Commit = Commit\n+@Commit = Commit\n\\ No newline at end of file\n",
+        binary: false
+      }
+
+      table(:merge_request_diff_files).create!(
+        base_diff_files_attributes.merge(relative_order: 1, new_path: 'test_file', old_path: 'test_file')
+      )
+      table(:merge_request_diff_files).create!(
+        base_diff_files_attributes.merge(relative_order: 2, new_path: 'test_file_2', old_path: 'test_file_2')
+      )
+    end
+  end
+end