Add Geo::PackageFileRegistry model

and its table.

config/initializers/0_inflections.rb

@@ -19,6 +19,7 @@ ActiveSupport::Inflector.inflections do |inflect|
     group_view
     job_artifact_registry
     lfs_object_registry
+    package_file_registry
     project_auto_devops
     project_registry
     project_statistics

ee/app/models/geo/package_file_registry.rb

+# frozen_string_literal: true
+
+class Geo::PackageFileRegistry < Geo::BaseRegistry
+  include ::Delay
+
+  STATE_VALUES = {
+    pending: 0,
+    started: 1,
+    synced: 2,
+    failed: 3
+  }.freeze
+
+  belongs_to :package_file, class_name: 'Packages::PackageFile'
+
+  scope :package_file_id_not_in, -> (ids) { where.not(package_file_id: ids) }
+  scope :never, -> { where(last_synced_at: nil) }
+  scope :failed, -> { with_state(:failed) }
+  scope :synced, -> { with_state(:synced) }
+  scope :retry_due, -> { where(arel_table[:retry_at].eq(nil).or(arel_table[:retry_at].lt(Time.now))) }
+
+  state_machine :state, initial: :pending do
+    state :pending, value: STATE_VALUES[:pending]
+    state :started, value: STATE_VALUES[:started]
+    state :synced, value: STATE_VALUES[:synced]
+    state :failed, value: STATE_VALUES[:failed]
+
+    before_transition any => :started do |registry, _|
+      registry.last_synced_at = Time.now
+    end
+
+    before_transition any => :pending do |registry, _|
+      registry.retry_at = 0
+      registry.retry_count = 0
+    end
+
+    before_transition any => :failed do |registry, _|
+      registry.retry_count += 1
+      registry.retry_at = registry.next_retry_time(registry.retry_count)
+    end
+
+    before_transition any => :synced do |registry, _|
+      registry.retry_count = 0
+      registry.last_sync_failure = nil
+      registry.retry_at = nil
+    end
+
+    event :start do
+      transition [:pending, :synced, :failed] => :started
+    end
+
+    event :synced do
+      transition [:started] => :synced
+    end
+
+    event :failed do
+      transition [:started] => :failed
+    end
+
+    event :resync do
+      transition [:synced, :failed] => :pending
+    end
+  end
+
+  # @return [Geo::PackageFileRegistry] an instance of this class
+  def self.for_model_record_id(id)
+    find_or_initialize_by(package_file_id: id)
+  end
+
+  def self.state_value(state_string)
+    STATE_VALUES[state_string]
+  end
+
+  # Override state machine failed! event method to record a failure message at
+  # the same time.
+  #
+  # @param [String] message error information
+  # @param [StandardError] error exception
+  def failed!(message, error = nil)
+    self.last_sync_failure = message
+    self.last_sync_failure += ": #{error.message}" if error.respond_to?(:message)
+
+    super()
+  end
+end

ee/db/geo/migrate/20200121194300_create_package_file_registry.rb

+# frozen_string_literal: true
+
+class CreatePackageFileRegistry < ActiveRecord::Migration[5.2]
+  DOWNTIME = false
+
+  def change
+    create_table :package_file_registry, id: :serial, force: :cascade do |t|
+      t.integer :package_file_id, null: false
+      t.integer :state, default: 0, null: false
+      t.integer :retry_count, default: 0
+      t.string :last_sync_failure, limit: 255
+      t.datetime_with_timezone :retry_at
+      t.datetime_with_timezone :last_synced_at
+      t.datetime_with_timezone :created_at, null: false
+
+      t.index :package_file_id, name: :index_package_file_registry_on_repository_id, using: :btree
+      t.index :retry_at, name: :index_package_file_registry_on_retry_at, using: :btree
+      t.index :state, name: :index_package_file_registry_on_state, using: :btree
+    end
+  end
+end

ee/db/geo/schema.rb

@@ -2,15 +2,15 @@
 # of editing this file, please use the migrations feature of Active Record to
 # incrementally modify your database, and then regenerate this schema definition.
 #
-# Note that this schema.rb definition is the authoritative source for your
-# database schema. If you need to create the application database on another
-# system, you should be using db:schema:load, not running all the migrations
-# from scratch. The latter is a flawed and unsustainable approach (the more migrations
-# you'll amass, the slower it'll run and the greater likelihood for issues).
+# This file is the source Rails uses to define your schema when running `rails
+# db:schema:load`. When creating a new database, `rails db:schema:load` tends to
+# be faster and is potentially less error prone than running all of your
+# migrations from scratch. Old migrations may fail to apply correctly if those
+# migrations use external dependencies or application code.
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2019_10_25_194337) do
+ActiveRecord::Schema.define(version: 2020_01_21_194300) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -91,6 +91,19 @@ ActiveRecord::Schema.define(version: 2019_10_25_194337) do
     t.index ["success"], name: "index_lfs_object_registry_on_success"
   end
 
+  create_table "package_file_registry", id: :serial, force: :cascade do |t|
+    t.integer "package_file_id", null: false
+    t.integer "state", default: 0, null: false
+    t.integer "retry_count", default: 0
+    t.string "last_sync_failure", limit: 255
+    t.datetime_with_timezone "retry_at"
+    t.datetime_with_timezone "last_synced_at"
+    t.datetime_with_timezone "created_at", null: false
+    t.index ["package_file_id"], name: "index_package_file_registry_on_repository_id"
+    t.index ["retry_at"], name: "index_package_file_registry_on_retry_at"
+    t.index ["state"], name: "index_package_file_registry_on_state"
+  end
+
   create_table "project_registry", id: :serial, force: :cascade do |t|
     t.integer "project_id", null: false
     t.datetime "last_repository_synced_at"

ee/spec/factories/geo/package_file_registry.rb

+# frozen_string_literal: true
+
+FactoryBot.define do
+  factory :package_file_registry, class: 'Geo::PackageFileRegistry' do
+    association :package_file, factory: [:package_file, :npm]
+    last_sync_failure { nil }
+    last_synced_at { nil }
+    state { Geo::PackageFileRegistry.state_value(:pending) }
+
+    trait :synced do
+      state { Geo::PackageFileRegistry.state_value(:synced) }
+      last_synced_at { 5.days.ago }
+    end
+
+    trait :failed do
+      state { Geo::PackageFileRegistry.state_value(:failed) }
+      last_synced_at { 1.day.ago }
+      retry_count { 2 }
+      last_sync_failure { 'Random error' }
+    end
+
+    trait :started do
+      state { Geo::PackageFileRegistry.state_value(:started) }
+      last_synced_at { 1.day.ago }
+      retry_count { 0 }
+    end
+  end
+end

ee/spec/models/geo/package_file_registry_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Geo::PackageFileRegistry, :geo, type: :model do
+  let_it_be(:registry) { create(:package_file_registry) }
+
+  specify 'factory is valid' do
+    expect(registry).to be_valid
+  end
+end