codesnips

activerecord

ruby 
class AddSlugToArticles < ActiveRecord::Migration[7.1]
  def change
    add_column :articles, :slug, :string
    add_index :articles, :slug, unique: true

    reversible do |dir|

Auto-Generating URL Slugs in Rails with a before_validation Callback and Friendly Finder

rails activerecord slugs
by codesnips 4 tabs
ruby 
require 'activerecord-import'

class BulkImportPostsService
  BATCH_SIZE = 1000

  def initialize(csv_file_path)

Bulk operations with ActiveRecord import

rails performance activerecord
by Alex Kumar 1 tab
ruby 
class Article < ApplicationRecord
  has_many :taggings, dependent: :destroy
  has_many :tags, through: :taggings

  scope :published, -> { where.not(published_at: nil) }

Filtering a Listing by Tags with a has_many :through Scope and a Query Object

rails activerecord has-many-through
by codesnips 3 tabs
ruby 
module QueryBudget
  class Counter
    IGNORED = %w[SCHEMA CACHE TRANSACTION].freeze

    attr_reader :count

Per-Request Query Budget (Detect Runaway Pages)

rails performance observability
by codesnips 4 tabs
ruby 
class AddSearchVectorToArticles < ActiveRecord::Migration[7.1]
  def up
    execute <<~SQL
      ALTER TABLE articles
      ADD COLUMN search_vector tsvector
      GENERATED ALWAYS AS (

Multi-Column Full Text Search with tsvector

rails postgres search
by codesnips 3 tabs
ruby 
class Reminder < ApplicationRecord
  belongs_to :user

  validates :time_zone, inclusion: { in: ActiveSupport::TimeZone::MAPPING.values }
  validates :local_time, presence: true

Time Zone Safe Scheduling

rails timezone scheduling
by codesnips 3 tabs
ruby 
class DebouncedReindexJob
  include Sidekiq::Job

  sidekiq_options queue: :indexing, retry: 5

  DEBOUNCE_DELAY = 5 # seconds

Debouncing Sidekiq Jobs Per-Record With Redis So Rapid Updates Coalesce Into One Run

rails sidekiq redis
by codesnips 3 tabs
ruby 
class ArticlesController < ApplicationController
  def index
    # Bounded queries: without preload, article.author in the view raises.
    @articles = Article
      .published
      .preload(:author, :tags)

Strict Loading to Catch N+1 in Development

rails activerecord performance
by codesnips 4 tabs
ruby 
class InventoryLevel < ApplicationRecord
  belongs_to :warehouse

  UPSERT_COLUMNS = %w[warehouse_id sku on_hand reserved updated_at].freeze

  def self.upsert_counts(rows)

Bulk-Upsert Inventory Counts in One Query From a Sidekiq Job

rails postgres upsert
by codesnips 3 tabs
ruby 
require "csv"

class ProductImporter
  BATCH_SIZE = 500

  attr_reader :errors, :inserted

Bulk-Insert a Product CSV in Rails with a Service Object and upsert_all

rails csv bulk-insert
by codesnips 3 tabs
ruby 
class Order < ApplicationRecord
  class InvalidTransition < StandardError; end

  enum status: { pending: 0, paid: 1, shipped: 2, cancelled: 3 }

  has_many :order_transitions, -> { order(:created_at) }, dependent: :destroy

Order State Machine With Guarded Transitions and an Audit Trail in Rails

rails state-machine activerecord
by codesnips 3 tabs
ruby 
class Product < ApplicationRecord
  has_many :reviews, dependent: :destroy

  scope :published, -> { where(published: true) }

  def average_rating

Russian Doll Fragment Caching with Touch Propagation in Rails

rails caching fragment-caching
by codesnips 4 tabs