Ruby Expert

Ruby专家

Expert guidance for Ruby development, including Ruby 3+ features, Rails framework, testing with RSpec, and Ruby best practices.

为Ruby开发提供专业指导，包括Ruby 3+特性、Rails框架、RSpec测试以及Ruby最佳实践。

Core Concepts

核心概念

Ruby 3+ Features

Ruby 3+ 新特性

Pattern matching
Ractors (parallel execution)
Fibers (cooperative concurrency)
Type signatures (RBS)
Endless methods
Numbered block parameters
Hash literal value omission

模式匹配
Ractors（并行执行）
Fibers（协作式并发）
类型签名（RBS）
极简方法定义
编号块参数
哈希字面量值省略

Object-Oriented

面向对象特性

Everything is an object
Classes and modules
Inheritance and mixins
Method visibility (public, private, protected)
Singleton methods and eigenclasses
Duck typing

一切皆对象
类与模块
继承与混入
方法可见性（public、private、protected）
单例方法与 eigenclass
鸭子类型

Functional Features

函数式特性

Blocks, procs, and lambdas
Higher-order functions (map, reduce, select)
Enumerables
Lazy evaluation

块、Proc与Lambda
高阶函数（map、reduce、select）
可枚举类型
惰性求值

Modern Ruby Syntax

现代Ruby语法

Pattern Matching (Ruby 3.0+)

模式匹配（Ruby 3.0+）

ruby

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ruby

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Case/in pattern matching

def process_response(response) case response in { status: 200, body: } puts "Success: #{body}" in { status: 404 } puts "Not found" in { status: 500..599, error: message } puts "Server error: #{message}" else puts "Unknown response" end end

Rightward assignment

response = { status: 200, body: "OK" } response => { status:, body: } puts status # 200 puts body # "OK"

Array pattern matching

def summarize(data) case data in [] "Empty" in [item] "Single item: #{item}" in [first, *rest] "First: #{first}, Rest: #{rest.length} items" end end

undefined

def summarize(data) case data in [] "Empty" in [item] "Single item: #{item}" in [first, *rest] "First: #{first}, Rest: #{rest.length} items" end end

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Endless Methods

极简方法定义

ruby

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ruby

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Single-line method definition

def greet(name) = "Hello, #{name}!"

def square(x) = x * x

def full_name = "#{first_name} #{last_name}"

class User attr_reader :name, :email

def initialize(name:, email:) = (@name = name; @email = email)

def admin? = @role == :admin end

undefined

def greet(name) = "Hello, #{name}!"

def square(x) = x * x

def full_name = "#{first_name} #{last_name}"

class User attr_reader :name, :email

def initialize(name:, email:) = (@name = name; @email = email)

def admin? = @role == :admin end

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Numbered Block Parameters

编号块参数

ruby

undefined

ruby

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Use _1, _2, etc. for block parameters

[1, 2, 3].map { _1 * 2 } # [2, 4, 6]

{ a: 1, b: 2 }.map { "#{_1}: #{_2}" } # ["a: 1", "b: 2"]

users.sort_by { [_1.last_name, _1.first_name] }

undefined

[1, 2, 3].map { _1 * 2 } # [2, 4, 6]

{ a: 1, b: 2 }.map { "#{_1}: #{_2}" } # ["a: 1", "b: 2"]

users.sort_by { [_1.last_name, _1.first_name] }

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Hash Literal Value Omission

哈希字面量值省略

ruby

name = "Alice"
age = 30
email = "alice@example.com"

ruby

name = "Alice"
age = 30
email = "alice@example.com"

Before

user = { name: name, age: age, email: email }

After (Ruby 3.1+)

user = { name:, age:, email: }

undefined

user = { name:, age:, email: }

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Ruby on Rails

Rails 7+ Application

Rails 7+ 应用示例

ruby

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ruby

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app/models/user.rb

class User < ApplicationRecord

Validations

validates :email, presence: true, uniqueness: true, format: { with: URI::MailTo::EMAIL_REGEXP } validates :name, presence: true, length: { minimum: 2, maximum: 100 } validates :age, numericality: { greater_than_or_equal_to: 18 }, allow_nil: true

Associations

has_many :posts, dependent: :destroy has_many :comments, dependent: :destroy has_many :likes, dependent: :destroy has_many :liked_posts, through: :likes, source: :post

Scopes

scope :active, -> { where(active: true) } scope :recent, -> { order(created_at: :desc) } scope :with_posts, -> { joins(:posts).distinct }

Callbacks

before_save :normalize_email after_create :send_welcome_email

Enums

enum role: { user: 0, moderator: 1, admin: 2 }

Instance methods

def full_name "#{first_name} #{last_name}" end

def admin? role == 'admin' end

private

def normalize_email self.email = email.downcase.strip end

def send_welcome_email UserMailer.welcome(self).deliver_later end end

class User < ApplicationRecord

Validations

validates :email, presence: true, uniqueness: true, format: { with: URI::MailTo::EMAIL_REGEXP } validates :name, presence: true, length: { minimum: 2, maximum: 100 } validates :age, numericality: { greater_than_or_equal_to: 18 }, allow_nil: true

Associations

has_many :posts, dependent: :destroy has_many :comments, dependent: :destroy has_many :likes, dependent: :destroy has_many :liked_posts, through: :likes, source: :post

Scopes

scope :active, -> { where(active: true) } scope :recent, -> { order(created_at: :desc) } scope :with_posts, -> { joins(:posts).distinct }

Callbacks

before_save :normalize_email after_create :send_welcome_email

Enums

enum role: { user: 0, moderator: 1, admin: 2 }

Instance methods

def full_name "#{first_name} #{last_name}" end

def admin? role == 'admin' end

private

def normalize_email self.email = email.downcase.strip end

def send_welcome_email UserMailer.welcome(self).deliver_later end end

app/models/post.rb

class Post < ApplicationRecord belongs_to :user has_many :comments, dependent: :destroy has_many :likes, dependent: :destroy has_many :liking_users, through: :likes, source: :user

has_one_attached :cover_image has_rich_text :content

validates :title, presence: true, length: { minimum: 5, maximum: 200 } validates :content, presence: true

scope :published, -> { where(published: true) } scope :by_user, ->(user) { where(user: user) } scope :search, ->(query) { where('title ILIKE ? OR content ILIKE ?', "%#{query}%", "%#{query}%") }

before_save :generate_slug

def publish! update!(published: true, published_at: Time.current) end

private

def generate_slug self.slug = title.parameterize end end

undefined

class Post < ApplicationRecord belongs_to :user has_many :comments, dependent: :destroy has_many :likes, dependent: :destroy has_many :liking_users, through: :likes, source: :user

has_one_attached :cover_image has_rich_text :content

validates :title, presence: true, length: { minimum: 5, maximum: 200 } validates :content, presence: true

scope :published, -> { where(published: true) } scope :by_user, ->(user) { where(user: user) } scope :search, ->(query) { where('title ILIKE ? OR content ILIKE ?', "%#{query}%", "%#{query}%") }

before_save :generate_slug

def publish! update!(published: true, published_at: Time.current) end

private

def generate_slug self.slug = title.parameterize end end

undefined

Controllers

控制器示例

ruby

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ruby

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app/controllers/api/v1/posts_controller.rb

module Api module V1 class PostsController < ApplicationController before_action :authenticate_user!, except: [:index, :show] before_action :set_post, only: [:show, :update, :destroy] before_action :authorize_post, only: [:update, :destroy]

  # GET /api/v1/posts
  def index
    @posts = Post.published
                 .includes(:user, :comments)
                 .page(params[:page])
                 .per(20)

    render json: @posts, each_serializer: PostSerializer
  end

  # GET /api/v1/posts/:id
  def show
    render json: @post, serializer: PostSerializer, include: [:user, :comments]
  end

  # POST /api/v1/posts
  def create
    @post = current_user.posts.build(post_params)

    if @post.save
      render json: @post, serializer: PostSerializer, status: :created
    else
      render json: { errors: @post.errors.full_messages }, status: :unprocessable_entity
    end
  end

  # PATCH/PUT /api/v1/posts/:id
  def update
    if @post.update(post_params)
      render json: @post, serializer: PostSerializer
    else
      render json: { errors: @post.errors.full_messages }, status: :unprocessable_entity
    end
  end

  # DELETE /api/v1/posts/:id
  def destroy
    @post.destroy
    head :no_content
  end

  private

  def set_post
    @post = Post.find(params[:id])
  rescue ActiveRecord::RecordNotFound
    render json: { error: 'Post not found' }, status: :not_found
  end

  def authorize_post
    unless @post.user == current_user || current_user.admin?
      render json: { error: 'Unauthorized' }, status: :forbidden
    end
  end

  def post_params
    params.require(:post).permit(:title, :content, :published, :cover_image)
  end
end

end end

undefined

module Api module V1 class PostsController < ApplicationController before_action :authenticate_user!, except: [:index, :show] before_action :set_post, only: [:show, :update, :destroy] before_action :authorize_post, only: [:update, :destroy]

  # GET /api/v1/posts
  def index
    @posts = Post.published
                 .includes(:user, :comments)
                 .page(params[:page])
                 .per(20)

    render json: @posts, each_serializer: PostSerializer
  end

  # GET /api/v1/posts/:id
  def show
    render json: @post, serializer: PostSerializer, include: [:user, :comments]
  end

  # POST /api/v1/posts
  def create
    @post = current_user.posts.build(post_params)

    if @post.save
      render json: @post, serializer: PostSerializer, status: :created
    else
      render json: { errors: @post.errors.full_messages }, status: :unprocessable_entity
    end
  end

  # PATCH/PUT /api/v1/posts/:id
  def update
    if @post.update(post_params)
      render json: @post, serializer: PostSerializer
    else
      render json: { errors: @post.errors.full_messages }, status: :unprocessable_entity
    end
  end

  # DELETE /api/v1/posts/:id
  def destroy
    @post.destroy
    head :no_content
  end

  private

  def set_post
    @post = Post.find(params[:id])
  rescue ActiveRecord::RecordNotFound
    render json: { error: 'Post not found' }, status: :not_found
  end

  def authorize_post
    unless @post.user == current_user || current_user.admin?
      render json: { error: 'Unauthorized' }, status: :forbidden
    end
  end

  def post_params
    params.require(:post).permit(:title, :content, :published, :cover_image)
  end
end

end end

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Active Record Queries

Active Record 查询

ruby

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Efficient queries

User.includes(:posts).where(posts: { published: true }) User.joins(:posts).group('users.id').having('COUNT(posts.id) > ?', 5) User.left_joins(:posts).where(posts: { id: nil }) # Users with no posts

Complex queries

Post.where('created_at > ?', 1.week.ago) .where(published: true) .order(created_at: :desc) .limit(10)

Find or create

user = User.find_or_create_by(email: 'user@example.com') do |u| u.name = 'New User' u.role = :user end

Upsert (Rails 6+)

User.upsert({ email: 'user@example.com', name: 'Alice' }, unique_by: :email)

Batch processing

User.find_each(batch_size: 100) do |user| user.update_subscription_status end

Transactions

ActiveRecord::Base.transaction do user.update!(balance: user.balance - amount) recipient.update!(balance: recipient.balance + amount) Transaction.create!(from: user, to: recipient, amount: amount) end

Raw SQL (when needed)

ActiveRecord::Base.connection.execute( "SELECT * FROM users WHERE created_at > '2024-01-01'" )

undefined

ActiveRecord::Base.connection.execute( "SELECT * FROM users WHERE created_at > '2024-01-01'" )

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Background Jobs (Sidekiq)

后台任务（Sidekiq）

ruby

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ruby

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app/jobs/send_email_job.rb

class SendEmailJob < ApplicationJob queue_as :default retry_on Net::SMTPServerBusy, wait: :exponentially_longer

def perform(user_id, email_type) user = User.find(user_id) case email_type when 'welcome' UserMailer.welcome(user).deliver_now when 'notification' UserMailer.notification(user).deliver_now end end end

class SendEmailJob < ApplicationJob queue_as :default retry_on Net::SMTPServerBusy, wait: :exponentially_longer

def perform(user_id, email_type) user = User.find(user_id) case email_type when 'welcome' UserMailer.welcome(user).deliver_now when 'notification' UserMailer.notification(user).deliver_now end end end

Usage

SendEmailJob.perform_later(user.id, 'welcome') SendEmailJob.set(wait: 1.hour).perform_later(user.id, 'notification')

undefined

SendEmailJob.perform_later(user.id, 'welcome') SendEmailJob.set(wait: 1.hour).perform_later(user.id, 'notification')

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Mailers

邮件发送器

ruby

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ruby

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app/mailers/user_mailer.rb

class UserMailer < ApplicationMailer default from: 'noreply@example.com'

def welcome(user) @user = user @url = 'https://example.com/login' mail(to: @user.email, subject: 'Welcome to My App') end

def notification(user, message) @user = user @message = message mail( to: @user.email, subject: 'New Notification', reply_to: 'support@example.com' ) end end

undefined

class UserMailer < ApplicationMailer default from: 'noreply@example.com'

def welcome(user) @user = user @url = 'https://example.com/login' mail(to: @user.email, subject: 'Welcome to My App') end

def notification(user, message) @user = user @message = message mail( to: @user.email, subject: 'New Notification', reply_to: 'support@example.com' ) end end

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Routes

路由配置

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config/routes.rb

Rails.application.routes.draw do root 'home#index'

RESTful resources

resources :posts do member do post :publish post :like end collection do get :trending end resources :comments, only: [:create, :destroy] end

Nested resources

resources :users do resources :posts, only: [:index, :show] end

Namespaced routes

namespace :api do namespace :v1 do resources :posts, only: [:index, :show, :create, :update, :destroy] resources :users, only: [:index, :show] end end

Constraints

constraints(subdomain: 'api') do scope module: 'api' do resources :posts end end

Custom routes

get '/about', to: 'pages#about' post '/contact', to: 'pages#contact' end

undefined

Rails.application.routes.draw do root 'home#index'

RESTful resources

resources :posts do member do post :publish post :like end collection do get :trending end resources :comments, only: [:create, :destroy] end

Nested resources

resources :users do resources :posts, only: [:index, :show] end

Namespaced routes

namespace :api do namespace :v1 do resources :posts, only: [:index, :show, :create, :update, :destroy] resources :users, only: [:index, :show] end end

Constraints

constraints(subdomain: 'api') do scope module: 'api' do resources :posts end end

Custom routes

get '/about', to: 'pages#about' post '/contact', to: 'pages#contact' end

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Testing with RSpec

RSpec测试

Model Specs

模型测试

ruby

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ruby

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spec/models/user_spec.rb

require 'rails_helper'

RSpec.describe User, type: :model do describe 'validations' do it { should validate_presence_of(:email) } it { should validate_uniqueness_of(:email) } it { should validate_presence_of(:name) } it { should validate_length_of(:name).is_at_least(2).is_at_most(100) } end

describe 'associations' do it { should have_many(:posts).dependent(:destroy) } it { should have_many(:comments).dependent(:destroy) } end

describe '#full_name' do it 'returns the full name' do user = User.new(first_name: 'Alice', last_name: 'Smith') expect(user.full_name).to eq('Alice Smith') end end

describe '#admin?' do it 'returns true for admin users' do user = User.new(role: :admin) expect(user).to be_admin end

it 'returns false for regular users' do
  user = User.new(role: :user)
  expect(user).not_to be_admin
end

end

describe 'callbacks' do it 'normalizes email before save' do user = create(:user, email: ' Alice@Example.COM ') expect(user.email).to eq('alice@example.com') end

it 'sends welcome email after create' do
  expect {
    create(:user)
  }.to have_enqueued_job(SendEmailJob).with(anything, 'welcome')
end

end end

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require 'rails_helper'

RSpec.describe User, type: :model do describe 'validations' do it { should validate_presence_of(:email) } it { should validate_uniqueness_of(:email) } it { should validate_presence_of(:name) } it { should validate_length_of(:name).is_at_least(2).is_at_most(100) } end

describe 'associations' do it { should have_many(:posts).dependent(:destroy) } it { should have_many(:comments).dependent(:destroy) } end

describe '#full_name' do it 'returns the full name' do user = User.new(first_name: 'Alice', last_name: 'Smith') expect(user.full_name).to eq('Alice Smith') end end

describe '#admin?' do it 'returns true for admin users' do user = User.new(role: :admin) expect(user).to be_admin end

it 'returns false for regular users' do
  user = User.new(role: :user)
  expect(user).not_to be_admin
end

end

describe 'callbacks' do it 'normalizes email before save' do user = create(:user, email: ' Alice@Example.COM ') expect(user.email).to eq('alice@example.com') end

it 'sends welcome email after create' do
  expect {
    create(:user)
  }.to have_enqueued_job(SendEmailJob).with(anything, 'welcome')
end

end end

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Controller Specs

控制器测试

ruby

undefined

ruby

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spec/controllers/posts_controller_spec.rb

require 'rails_helper'

RSpec.describe PostsController, type: :controller do let(:user) { create(:user) } let(:post) { create(:post, user: user) }

describe 'GET #index' do it 'returns a success response' do get :index expect(response).to have_http_status(:success) end

it 'assigns @posts' do
  post1 = create(:post, published: true)
  post2 = create(:post, published: true)
  get :index
  expect(assigns(:posts)).to match_array([post1, post2])
end

end

describe 'POST #create' do context 'when authenticated' do before { sign_in user }

  context 'with valid params' do
    let(:valid_params) { { post: { title: 'Test Post', content: 'Content' } } }

    it 'creates a new post' do
      expect {
        post :create, params: valid_params
      }.to change(Post, :count).by(1)
    end

    it 'returns created status' do
      post :create, params: valid_params
      expect(response).to have_http_status(:created)
    end
  end

  context 'with invalid params' do
    let(:invalid_params) { { post: { title: '' } } }

    it 'does not create a post' do
      expect {
        post :create, params: invalid_params
      }.not_to change(Post, :count)
    end

    it 'returns unprocessable entity status' do
      post :create, params: invalid_params
      expect(response).to have_http_status(:unprocessable_entity)
    end
  end
end

context 'when not authenticated' do
  it 'returns unauthorized status' do
    post :create, params: { post: { title: 'Test' } }
    expect(response).to have_http_status(:unauthorized)
  end
end

end end

undefined

require 'rails_helper'

RSpec.describe PostsController, type: :controller do let(:user) { create(:user) } let(:post) { create(:post, user: user) }

describe 'GET #index' do it 'returns a success response' do get :index expect(response).to have_http_status(:success) end

it 'assigns @posts' do
  post1 = create(:post, published: true)
  post2 = create(:post, published: true)
  get :index
  expect(assigns(:posts)).to match_array([post1, post2])
end

end

describe 'POST #create' do context 'when authenticated' do before { sign_in user }

  context 'with valid params' do
    let(:valid_params) { { post: { title: 'Test Post', content: 'Content' } } }

    it 'creates a new post' do
      expect {
        post :create, params: valid_params
      }.to change(Post, :count).by(1)
    end

    it 'returns created status' do
      post :create, params: valid_params
      expect(response).to have_http_status(:created)
    end
  end

  context 'with invalid params' do
    let(:invalid_params) { { post: { title: '' } } }

    it 'does not create a post' do
      expect {
        post :create, params: invalid_params
      }.not_to change(Post, :count)
    end

    it 'returns unprocessable entity status' do
      post :create, params: invalid_params
      expect(response).to have_http_status(:unprocessable_entity)
    end
  end
end

context 'when not authenticated' do
  it 'returns unauthorized status' do
    post :create, params: { post: { title: 'Test' } }
    expect(response).to have_http_status(:unauthorized)
  end
end

end end

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Request Specs

请求测试

ruby

undefined

ruby

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spec/requests/api/v1/posts_spec.rb

require 'rails_helper'

RSpec.describe 'Api::V1::Posts', type: :request do let(:user) { create(:user) } let(:headers) { { 'Authorization' => "Bearer #{user.auth_token}" } }

describe 'GET /api/v1/posts' do before do create_list(:post, 3, published: true) create(:post, published: false) end

it 'returns published posts' do
  get '/api/v1/posts'
  expect(response).to have_http_status(:success)
  expect(JSON.parse(response.body).length).to eq(3)
end

it 'paginates results' do
  create_list(:post, 25, published: true)
  get '/api/v1/posts', params: { page: 2 }
  expect(JSON.parse(response.body).length).to eq(8)  # 28 total, 20 per page
end

end

describe 'POST /api/v1/posts' do context 'with valid params' do let(:valid_params) do { post: { title: 'Test Post', content: 'Content' } } end

  it 'creates a post' do
    expect {
      post '/api/v1/posts', params: valid_params, headers: headers
    }.to change(Post, :count).by(1)
  end

  it 'returns the created post' do
    post '/api/v1/posts', params: valid_params, headers: headers
    expect(response).to have_http_status(:created)
    expect(JSON.parse(response.body)['title']).to eq('Test Post')
  end
end

end end

undefined

require 'rails_helper'

RSpec.describe 'Api::V1::Posts', type: :request do let(:user) { create(:user) } let(:headers) { { 'Authorization' => "Bearer #{user.auth_token}" } }

describe 'GET /api/v1/posts' do before do create_list(:post, 3, published: true) create(:post, published: false) end

it 'returns published posts' do
  get '/api/v1/posts'
  expect(response).to have_http_status(:success)
  expect(JSON.parse(response.body).length).to eq(3)
end

it 'paginates results' do
  create_list(:post, 25, published: true)
  get '/api/v1/posts', params: { page: 2 }
  expect(JSON.parse(response.body).length).to eq(8)  # 28 total, 20 per page
end

end

describe 'POST /api/v1/posts' do context 'with valid params' do let(:valid_params) do { post: { title: 'Test Post', content: 'Content' } } end

  it 'creates a post' do
    expect {
      post '/api/v1/posts', params: valid_params, headers: headers
    }.to change(Post, :count).by(1)
  end

  it 'returns the created post' do
    post '/api/v1/posts', params: valid_params, headers: headers
    expect(response).to have_http_status(:created)
    expect(JSON.parse(response.body)['title']).to eq('Test Post')
  end
end

end end

undefined

FactoryBot

FactoryBot工厂

ruby

undefined

ruby

undefined

spec/factories/users.rb

FactoryBot.define do factory :user do sequence(:email) { |n| "user#{n}@example.com" } name { Faker::Name.name } password { 'password123' } role { :user }

trait :admin do
  role { :admin }
end

trait :with_posts do
  transient do
    posts_count { 5 }
  end

  after(:create) do |user, evaluator|
    create_list(:post, evaluator.posts_count, user: user)
  end
end

end

factory :post do association :user title { Faker::Lorem.sentence } content { Faker::Lorem.paragraph } published { false }

trait :published do
  published { true }
  published_at { Time.current }
end

end end

FactoryBot.define do factory :user do sequence(:email) { |n| "user#{n}@example.com" } name { Faker::Name.name } password { 'password123' } role { :user }

trait :admin do
  role { :admin }
end

trait :with_posts do
  transient do
    posts_count { 5 }
  end

  after(:create) do |user, evaluator|
    create_list(:post, evaluator.posts_count, user: user)
  end
end

end

factory :post do association :user title { Faker::Lorem.sentence } content { Faker::Lorem.paragraph } published { false }

trait :published do
  published { true }
  published_at { Time.current }
end

end end

Usage

user = create(:user) admin = create(:user, :admin) user_with_posts = create(:user, :with_posts, posts_count: 10) published_post = create(:post, :published)

undefined

user = create(:user) admin = create(:user, :admin) user_with_posts = create(:user, :with_posts, posts_count: 10) published_post = create(:post, :published)

undefined

Metaprogramming

元编程

ruby

undefined

ruby

undefined

Define methods dynamically

class User %w[name email phone].each do |attr| define_method("#{attr}_present?") do send(attr).present? end end end

Method missing

class Configuration def initialize @settings = {} end

def method_missing(method, *args) method_name = method.to_s if method_name.end_with?('=') @settings[method_name.chomp('=')] = args.first else @settings[method_name] end end

def respond_to_missing?(method, include_private = false) true end end

config = Configuration.new config.api_key = 'secret' config.api_key # => 'secret'

class Configuration def initialize @settings = {} end

def method_missing(method, *args) method_name = method.to_s if method_name.end_with?('=') @settings[method_name.chomp('=')] = args.first else @settings[method_name] end end

def respond_to_missing?(method, include_private = false) true end end

config = Configuration.new config.api_key = 'secret' config.api_key # => 'secret'

Class macros

module Timestampable def self.included(base) base.extend(ClassMethods) end

module ClassMethods def timestampable before_save :set_timestamps

  define_method(:set_timestamps) do
    self.updated_at = Time.current
    self.created_at ||= Time.current
  end
end

end end

class Post include Timestampable timestampable end

undefined

module Timestampable def self.included(base) base.extend(ClassMethods) end

module ClassMethods def timestampable before_save :set_timestamps

  define_method(:set_timestamps) do
    self.updated_at = Time.current
    self.created_at ||= Time.current
  end
end

end end

class Post include Timestampable timestampable end

undefined

Best Practices

最佳实践

Code Style

代码风格

Follow Ruby Style Guide
Use 2-space indentation
Prefer symbols over strings for keys
Use
```
snake_case
```
for methods and variables
Use
```
CamelCase
```
for classes
Use meaningful variable names

遵循Ruby风格指南
使用2空格缩进
优先使用符号而非字符串作为键
方法和变量使用
```
snake_case
```
命名
类使用
```
CamelCase
```
命名
使用有意义的变量名

Performance

性能优化

Use
```
includes
```
to avoid N+1 queries
Add database indexes on foreign keys
Use
```
select
```
to load only needed columns
Use
```
find_each
```
for large datasets
Cache expensive computations

使用
```
includes
```
避免N+1查询
为外键添加数据库索引
使用
```
select
```
仅加载所需列
处理大数据集时使用
```
find_each
```
缓存耗时计算结果

Security

安全规范

Use strong parameters in controllers
Sanitize user input
Protect against SQL injection (use parameterized queries)
Use CSRF protection
Implement authentication and authorization
Keep dependencies updated

控制器中使用强参数
对用户输入进行 sanitize 处理
防范SQL注入（使用参数化查询）
启用CSRF保护
实现身份认证与授权
及时更新依赖包

Anti-Patterns to Avoid

需避免的反模式

❌ Fat models: Extract logic to service objects ❌ N+1 queries: Use

includes

or

eager_load

❌ Long controller actions: Extract to services ❌ Missing indexes: Add indexes on foreign keys ❌ Skipping validations: Always validate data ❌ Exposing internals: Use serializers for API responses ❌ Global state: Avoid global variables and class variables

❌ 胖模型：将逻辑提取到服务对象中 ❌ N+1查询：使用

includes

或

eager_load

❌ 控制器动作过长：提取到服务层 ❌ 缺失索引：为外键添加索引 ❌ 跳过验证：始终对数据进行验证 ❌ 暴露内部实现：API响应使用序列化器 ❌ 全局状态：避免全局变量和类变量

Resources

参考资源

Ruby Documentation: https://ruby-doc.org/
Rails Guides: https://guides.rubyonrails.org/
RSpec: https://rspec.info/
Ruby Style Guide: https://rubystyle.guide/
Rails API: https://api.rubyonrails.org/

Ruby文档：https://ruby-doc.org/
Rails指南：https://guides.rubyonrails.org/
RSpec官网：https://rspec.info/
Ruby风格指南：https://rubystyle.guide/
Rails API文档：https://api.rubyonrails.org/

ruby-expert

Original

Translation

Ruby Expert

Ruby专家

Core Concepts

核心概念

Ruby 3+ Features

Ruby 3+ 新特性

Object-Oriented

面向对象特性

Functional Features

函数式特性

Modern Ruby Syntax

现代Ruby语法

Pattern Matching (Ruby 3.0+)

模式匹配（Ruby 3.0+）

Case/in pattern matching

Case/in pattern matching

Rightward assignment

Rightward assignment

Array pattern matching

Array pattern matching

Endless Methods

极简方法定义

Single-line method definition

Single-line method definition

Numbered Block Parameters

编号块参数

Use _1, _2, etc. for block parameters

Use _1, _2, etc. for block parameters

Hash Literal Value Omission

哈希字面量值省略

Before

Before

After (Ruby 3.1+)

After (Ruby 3.1+)

Ruby on Rails

Ruby on Rails

Rails 7+ Application

Rails 7+ 应用示例

app/models/user.rb

app/models/user.rb

Validations

Associations

Scopes

Callbacks

Enums

Instance methods

Validations

Associations

Scopes

Callbacks

Enums

Instance methods

app/models/post.rb

app/models/post.rb

Controllers

控制器示例

app/controllers/api/v1/posts_controller.rb

app/controllers/api/v1/posts_controller.rb

Active Record Queries

Active Record 查询

Efficient queries

Efficient queries

Complex queries

Complex queries

Find or create

Find or create

Upsert (Rails 6+)

Upsert (Rails 6+)

Batch processing

Batch processing

Transactions

Transactions

Raw SQL (when needed)

Raw SQL (when needed)

Background Jobs (Sidekiq)

后台任务（Sidekiq）

app/jobs/send_email_job.rb