codesnips

activerecord

ruby 
class ImportResult
  RowError = Struct.new(:line, :messages)

  attr_reader :imported, :row_errors

  def initialize

Streaming CSV Product Import With Per-Row Validation and Error Reporting in Rails

rails csv service-object
by codesnips 3 tabs
ruby 
class PriceBreakdown < Struct.new(:subtotal_cents, :discount_cents, :tax_cents, keyword_init: true)
  def initialize(*)
    super
    freeze
  end

Memoizing a Pricing Breakdown as an Immutable Value Object in Rails

rails memoization value-object
by codesnips 3 tabs
ruby 
class LastSeenTracker
  THROTTLE = 5.minutes
  PENDING_KEY = "pending:last_seen".freeze

  class << self
    def touch(user_id, at: Time.current)

Database “Last Seen” without Hot Row Updates

rails performance redis
by codesnips 3 tabs
ruby 
class CreateReservations < ActiveRecord::Migration[7.1]
  def up
    enable_extension "btree_gist" unless extension_enabled?("btree_gist")

    create_table :reservations do |t|
      t.references :room, null: false, foreign_key: true

DB-Level “no overlapping ranges” with exclusion constraint

rails postgres exclusion-constraint
by codesnips 3 tabs
erb 
<%= form_with url: bulk_update_orders_path, method: :patch, data: { turbo_confirm: "Update selected orders?" } do %>
  <div class="batch-toolbar">
    <%= select_tag :status,
          options_for_select(Order.statuses.keys.map { |s| [s.humanize, s] }),
          prompt: "Set status to\u2026" %>
    <%= submit_tag "Apply to selected", class: "btn" %>

Bulk-Updating Order Statuses with a Checkbox Collection and update_all Batch Action in Rails

rails activerecord update-all
by codesnips 3 tabs
ruby 
class Coupon < ApplicationRecord
  before_validation :normalize_code

  validates :code,
            coupon_code: { min_length: 6 },
            uniqueness: { case_sensitive: false }

Validating Coupon Codes with a Custom EachValidator in Rails

rails validations activerecord
by codesnips 3 tabs
ruby 
class CreateComments < ActiveRecord::Migration[6.1]
  def change
    create_table :comments do |t|
      t.references :commentable, polymorphic: true, null: false
      t.references :author, null: false, foreign_key: { to_table: :users }
      t.text :body, null: false

Polymorphic associations for flexible relationships

rails activerecord database
by Alex Kumar 3 tabs
ruby 
class DashboardMetrics
  include ActiveModel::Model

  attr_reader :account

  def initialize(account)

Expiring Dashboard Fragment Caches with a Versioned Composite Cache Key in Rails

rails caching fragment-caching
by codesnips 3 tabs
ruby 
class ShippedEmailJob
  include Sidekiq::Job
  sidekiq_options queue: :mailers, retry: 5

  def perform(order_id)
    order = Order.find_by(id: order_id)

Fan Out Notifications to Email and SMS Using an ActiveRecord Observer

rails activerecord observer
by codesnips 3 tabs
ruby 
class InvoicesController < ApplicationController
  def index
    invoices = InvoicesQuery.new(current_account.invoices, filter_params).call

    @invoices = invoices.page(params[:page]).per(25)
    render :index

Building a Composable Query Object for Filtering Rails ActiveRecord Scopes

rails activerecord query-object
by codesnips 3 tabs
ruby 
class AddSlugToPosts < ActiveRecord::Migration[7.1]
  def change
    add_column :posts, :slug, :string, null: false
    add_index :posts, :slug, unique: true
  end
end

Database-Backed Unique Slugs with Retry

rails postgres slugs
by codesnips 4 tabs
ruby 
class AddSoftDeleteToUsers < ActiveRecord::Migration[7.1]
  def change
    add_column :users, :deleted_at, :datetime

    add_index :users, :deleted_at, where: "deleted_at IS NULL", name: "index_users_on_live"

Soft-Delete with a Default Scope, Restore Action, and Unique Index Guard in Rails

rails activerecord soft-delete
by codesnips 3 tabs