rails

Rails Framework Skill - Quick Reference

Framework: Ruby on Rails 7+ For Agent: backend-developer Purpose: Fast lookup of common Rails patterns and conventions

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1. Rails MVC Patterns

Controllers (RESTful Actions)

class PostsController < ApplicationController
  before_action :set_post, only: %i[show edit update destroy]
  before_action :authenticate_user!, except: %i[index show]

  def index
    @posts = Post.published.order(created_at: :desc).page(params[:page])
  end

  def show
    # @post set by before_action
  end

  def new
    @post = Post.new
  end

  def create
    @post = current_user.posts.build(post_params)
    if @post.save
      redirect_to @post, notice: 'Post created successfully.'
    else
      render :new, status: :unprocessable_entity
    end
  end

  def edit
    # @post set by before_action
  end

  def update
    if @post.update(post_params)
      redirect_to @post, notice: 'Post updated successfully.'
    else
      render :edit, status: :unprocessable_entity
    end
  end

  def destroy
    @post.destroy
    redirect_to posts_url, notice: 'Post deleted successfully.'
  end

  private

  def set_post
    @post = Post.find(params[:id])
  end

  def post_params
    params.require(:post).permit(:title, :body, :published, :category_id, tag_ids: [])
  end
end

Models (Active Record)

class Post < ApplicationRecord
  # Associations
  belongs_to :author, class_name: 'User'
  belongs_to :category
  has_many :comments, dependent: :destroy
  has_many :taggings, dependent: :destroy
  has_many :tags, through: :taggings

  # Validations
  validates :title, presence: true, length: { minimum: 5, maximum: 200 }
  validates :body, presence: true
  validates :author, presence: true

  # Scopes
  scope :published, -> { where(published: true) }
  scope :recent, -> { order(created_at: :desc) }
  scope :by_author, ->(user) { where(author: user) }

  # Callbacks
  before_save :generate_slug
  after_create :notify_subscribers

  # Class methods
  def self.search(query)
    where('title ILIKE ? OR body ILIKE ?', "%#{query}%", "%#{query}%")
  end

  # Instance methods
  def published?
    published && published_at.present?
  end

  private

  def generate_slug
    self.slug = title.parameterize if title_changed?
  end

  def notify_subscribers
    NotifySubscribersJob.perform_later(id)
  end
end