Ruby Rails Application

Ruby on Rails 应用程序

Overview

概述

Build comprehensive Ruby on Rails applications with proper model associations, RESTful controllers, Active Record queries, authentication systems, middleware chains, and view rendering following Rails conventions.

遵循Rails约定，构建包含完善模型关联、RESTful控制器、Active Record查询、身份验证系统、中间件链和视图渲染的Ruby on Rails应用程序。

When to Use

适用场景

Building Rails web applications
Implementing Active Record models with associations
Creating RESTful controllers and actions
Integrating authentication and authorization
Building complex database relationships
Implementing Rails middleware and filters

构建Rails Web应用程序
实现带有关联关系的Active Record模型
创建RESTful控制器及动作
集成身份验证与授权功能
构建复杂的数据库关系
实现Rails中间件与过滤器

Instructions

操作步骤

1. Rails Project Setup

1. Rails 项目搭建

bash

rails new myapp --api --database=postgresql
cd myapp
rails db:create

bash

rails new myapp --api --database=postgresql
cd myapp
rails db:create

2. Models with Active Record

2. 基于Active Record的模型

ruby

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ruby

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app/models/user.rb

class User < ApplicationRecord has_many :posts, dependent: :destroy has_many :comments, dependent: :destroy

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

validates :email, presence: true, uniqueness: true, format: { with: URI::MailTo::EMAIL_REGEXP } validates :password, presence: true, length: { minimum: 8 }, if: :new_record? validates :first_name, :last_name, presence: true

has_secure_password

before_save :downcase_email

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

def active? is_active end

private

def downcase_email self.email = email.downcase end end

class User < ApplicationRecord has_many :posts, dependent: :destroy has_many :comments, dependent: :destroy

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

validates :email, presence: true, uniqueness: true, format: { with: URI::MailTo::EMAIL_REGEXP } validates :password, presence: true, length: { minimum: 8 }, if: :new_record? validates :first_name, :last_name, presence: true

has_secure_password

before_save :downcase_email

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

def active? is_active end

private

def downcase_email self.email = email.downcase end end

app/models/post.rb

class Post < ApplicationRecord belongs_to :user has_many :comments, dependent: :destroy

enum status: { draft: 0, published: 1, archived: 2 }

validates :title, presence: true, length: { minimum: 1, maximum: 255 } validates :content, presence: true, length: { minimum: 1 } validates :user_id, presence: true

scope :published, -> { where(status: :published) } scope :recent, -> { order(created_at: :desc) } scope :by_author, ->(user_id) { where(user_id: user_id) }

def publish! update(status: :published) end

def unpublish! update(status: :draft) end end

class Post < ApplicationRecord belongs_to :user has_many :comments, dependent: :destroy

enum status: { draft: 0, published: 1, archived: 2 }

validates :title, presence: true, length: { minimum: 1, maximum: 255 } validates :content, presence: true, length: { minimum: 1 } validates :user_id, presence: true

scope :published, -> { where(status: :published) } scope :recent, -> { order(created_at: :desc) } scope :by_author, ->(user_id) { where(user_id: user_id) }

def publish! update(status: :published) end

def unpublish! update(status: :draft) end end

app/models/comment.rb

class Comment < ApplicationRecord belongs_to :user belongs_to :post

validates :content, presence: true, length: { minimum: 1 } validates :user_id, :post_id, presence: true

scope :recent, -> { order(created_at: :desc) } scope :by_author, ->(user_id) { where(user_id: user_id) } end

undefined

class Comment < ApplicationRecord belongs_to :user belongs_to :post

validates :content, presence: true, length: { minimum: 1 } validates :user_id, :post_id, presence: true

scope :recent, -> { order(created_at: :desc) } scope :by_author, ->(user_id) { where(user_id: user_id) } end

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3. Database Migrations

3. 数据库迁移

ruby

undefined

ruby

undefined

db/migrate/20240101120000_create_users.rb

class CreateUsers < ActiveRecord::Migration[7.0] def change create_table :users do |t| t.string :email, null: false t.string :password_digest, null: false t.string :first_name, null: false t.string :last_name, null: false t.integer :role, default: 0 t.boolean :is_active, default: true t.timestamps end

add_index :users, :email, unique: true
add_index :users, :role

end end

class CreateUsers < ActiveRecord::Migration[7.0] def change create_table :users do |t| t.string :email, null: false t.string :password_digest, null: false t.string :first_name, null: false t.string :last_name, null: false t.integer :role, default: 0 t.boolean :is_active, default: true t.timestamps end

add_index :users, :email, unique: true
add_index :users, :role

end end

db/migrate/20240101120001_create_posts.rb

class CreatePosts < ActiveRecord::Migration[7.0] def change create_table :posts do |t| t.string :title, null: false t.text :content, null: false t.integer :status, default: 0 t.references :user, null: false, foreign_key: true t.timestamps end

add_index :posts, :status
add_index :posts, [:user_id, :status]

end end

class CreatePosts < ActiveRecord::Migration[7.0] def change create_table :posts do |t| t.string :title, null: false t.text :content, null: false t.integer :status, default: 0 t.references :user, null: false, foreign_key: true t.timestamps end

add_index :posts, :status
add_index :posts, [:user_id, :status]

end end

db/migrate/20240101120002_create_comments.rb

class CreateComments < ActiveRecord::Migration[7.0] def change create_table :comments do |t| t.text :content, null: false t.references :user, null: false, foreign_key: true t.references :post, null: false, foreign_key: true t.timestamps end

add_index :comments, [:post_id, :created_at]
add_index :comments, [:user_id, :created_at]

end end

undefined

class CreateComments < ActiveRecord::Migration[7.0] def change create_table :comments do |t| t.text :content, null: false t.references :user, null: false, foreign_key: true t.references :post, null: false, foreign_key: true t.timestamps end

add_index :comments, [:post_id, :created_at]
add_index :comments, [:user_id, :created_at]

end end

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4. Controllers with RESTful Actions

4. 带RESTful动作的控制器

ruby

undefined

ruby

undefined

app/controllers/api/v1/users_controller.rb

module Api module V1 class UsersController < ApplicationController before_action :authenticate_request, except: [:create] before_action :set_user, only: [:show, :update, :destroy] before_action :authorize_user!, only: [:update, :destroy]

  def index
    users = User.all
    users = users.where("email ILIKE ?", "%#{params[:q]}%") if params[:q].present?
    users = users.page(params[:page]).per(params[:limit] || 20)

    render json: {
      data: users,
      pagination: pagination_data(users)
    }
  end

  def show
    render json: @user
  end

  def create
    user = User.new(user_params)

    if user.save
      token = encode_token(user.id)
      render json: {
        user: user,
        token: token
      }, status: :created
    else
      render json: { errors: user.errors.full_messages }, status: :unprocessable_entity
    end
  end

  def update
    if @user.update(user_params)
      render json: @user
    else
      render json: { errors: @user.errors.full_messages }, status: :unprocessable_entity
    end
  end

  def destroy
    @user.destroy
    head :no_content
  end

  private

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

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

  def user_params
    params.require(:user).permit(:email, :password, :first_name, :last_name)
  end

  def pagination_data(collection)
    {
      page: collection.current_page,
      per_page: collection.limit_value,
      total: collection.total_count,
      total_pages: collection.total_pages
    }
  end
end

end end

module Api module V1 class UsersController < ApplicationController before_action :authenticate_request, except: [:create] before_action :set_user, only: [:show, :update, :destroy] before_action :authorize_user!, only: [:update, :destroy]

  def index
    users = User.all
    users = users.where("email ILIKE ?", "%#{params[:q]}%") if params[:q].present?
    users = users.page(params[:page]).per(params[:limit] || 20)

    render json: {
      data: users,
      pagination: pagination_data(users)
    }
  end

  def show
    render json: @user
  end

  def create
    user = User.new(user_params)

    if user.save
      token = encode_token(user.id)
      render json: {
        user: user,
        token: token
      }, status: :created
    else
      render json: { errors: user.errors.full_messages }, status: :unprocessable_entity
    end
  end

  def update
    if @user.update(user_params)
      render json: @user
    else
      render json: { errors: @user.errors.full_messages }, status: :unprocessable_entity
    end
  end

  def destroy
    @user.destroy
    head :no_content
  end

  private

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

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

  def user_params
    params.require(:user).permit(:email, :password, :first_name, :last_name)
  end

  def pagination_data(collection)
    {
      page: collection.current_page,
      per_page: collection.limit_value,
      total: collection.total_count,
      total_pages: collection.total_pages
    }
  end
end

end end

app/controllers/api/v1/posts_controller.rb

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

  def index
    posts = Post.published.recent
    posts = posts.by_author(params[:author_id]) if params[:author_id].present?
    posts = posts.where("title ILIKE ?", "%#{params[:q]}%") if params[:q].present?
    posts = posts.page(params[:page]).per(params[:limit] || 20)

    render json: {
      data: posts,
      pagination: pagination_data(posts)
    }
  end

  def show
    if @post.published? || current_user&.id == @post.user_id
      render json: @post
    else
      render json: { error: 'Post not found' }, status: :not_found
    end
  end

  def create
    @post = current_user.posts.build(post_params)

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

  def update
    if @post.update(post_params)
      render json: @post
    else
      render json: { errors: @post.errors.full_messages }, status: :unprocessable_entity
    end
  end

  def destroy
    @post.destroy
    head :no_content
  end

  def publish
    @post.publish!
    render json: @post
  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_owner!
    unless current_user.id == @post.user_id || current_user.admin?
      render json: { error: 'Unauthorized' }, status: :forbidden
    end
  end

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

  def pagination_data(collection)
    {
      page: collection.current_page,
      per_page: collection.limit_value,
      total: collection.total_count
    }
  end
end

end end

undefined

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

  def index
    posts = Post.published.recent
    posts = posts.by_author(params[:author_id]) if params[:author_id].present?
    posts = posts.where("title ILIKE ?", "%#{params[:q]}%") if params[:q].present?
    posts = posts.page(params[:page]).per(params[:limit] || 20)

    render json: {
      data: posts,
      pagination: pagination_data(posts)
    }
  end

  def show
    if @post.published? || current_user&.id == @post.user_id
      render json: @post
    else
      render json: { error: 'Post not found' }, status: :not_found
    end
  end

  def create
    @post = current_user.posts.build(post_params)

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

  def update
    if @post.update(post_params)
      render json: @post
    else
      render json: { errors: @post.errors.full_messages }, status: :unprocessable_entity
    end
  end

  def destroy
    @post.destroy
    head :no_content
  end

  def publish
    @post.publish!
    render json: @post
  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_owner!
    unless current_user.id == @post.user_id || current_user.admin?
      render json: { error: 'Unauthorized' }, status: :forbidden
    end
  end

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

  def pagination_data(collection)
    {
      page: collection.current_page,
      per_page: collection.limit_value,
      total: collection.total_count
    }
  end
end

end end

undefined

5. Authentication with JWT

5. 基于JWT的身份验证

ruby

undefined

ruby

undefined

app/controllers/application_controller.rb

class ApplicationController < ActionController::API include ActionController::Cookies

SECRET_KEY = Rails.application.secrets.secret_key_base

def encode_token(user_id) payload = { user_id: user_id, exp: 24.hours.from_now.to_i } JWT.encode(payload, SECRET_KEY, 'HS256') end

def decode_token(token) begin JWT.decode(token, SECRET_KEY, true, { algorithm: 'HS256' }) rescue JWT::ExpiredSignature, JWT::DecodeError nil end end

def authenticate_request header = request.headers['Authorization'] token = header.split(' ').last if header.present?

decoded = decode_token(token)
if decoded
  @current_user_id = decoded[0]['user_id']
  @current_user = User.find(@current_user_id)
else
  render json: { error: 'Unauthorized' }, status: :unauthorized
end

end

def current_user @current_user end

def logged_in? current_user.present? end end

class ApplicationController < ActionController::API include ActionController::Cookies

SECRET_KEY = Rails.application.secrets.secret_key_base

def encode_token(user_id) payload = { user_id: user_id, exp: 24.hours.from_now.to_i } JWT.encode(payload, SECRET_KEY, 'HS256') end

def decode_token(token) begin JWT.decode(token, SECRET_KEY, true, { algorithm: 'HS256' }) rescue JWT::ExpiredSignature, JWT::DecodeError nil end end

def authenticate_request header = request.headers['Authorization'] token = header.split(' ').last if header.present?

decoded = decode_token(token)
if decoded
  @current_user_id = decoded[0]['user_id']
  @current_user = User.find(@current_user_id)
else
  render json: { error: 'Unauthorized' }, status: :unauthorized
end

end

def current_user @current_user end

def logged_in? current_user.present? end end

config/routes.rb

Rails.application.routes.draw do namespace :api do namespace :v1 do post 'auth/login', to: 'auth#login' post 'auth/register', to: 'auth#register'

  resources :users
  resources :posts do
    member do
      patch :publish
    end
    resources :comments, only: [:index, :create, :destroy]
  end
end

end end

undefined

Rails.application.routes.draw do namespace :api do namespace :v1 do post 'auth/login', to: 'auth#login' post 'auth/register', to: 'auth#register'

  resources :users
  resources :posts do
    member do
      patch :publish
    end
    resources :comments, only: [:index, :create, :destroy]
  end
end

end end

undefined

6. Active Record Queries

6. Active Record 查询

ruby

undefined

ruby

undefined

app/services/post_service.rb

class PostService def self.get_user_posts(user_id, status: nil) posts = Post.by_author(user_id) posts = posts.where(status: status) if status.present? posts.recent end

def self.trending_posts(limit: 10) Post.published .joins(:comments) .group('posts.id') .order('COUNT(comments.id) DESC') .limit(limit) end

def self.search_posts(query) Post.published .where("title ILIKE ? OR content ILIKE ?", "%#{query}%", "%#{query}%") .recent end

def self.archive_old_drafts(days: 30) Post.where(status: :draft) .where('created_at < ?', days.days.ago) .update_all(status: :archived) end end

class PostService def self.get_user_posts(user_id, status: nil) posts = Post.by_author(user_id) posts = posts.where(status: status) if status.present? posts.recent end

def self.trending_posts(limit: 10) Post.published .joins(:comments) .group('posts.id') .order('COUNT(comments.id) DESC') .limit(limit) end

def self.search_posts(query) Post.published .where("title ILIKE ? OR content ILIKE ?", "%#{query}%", "%#{query}%") .recent end

def self.archive_old_drafts(days: 30) Post.where(status: :draft) .where('created_at < ?', days.days.ago) .update_all(status: :archived) end end

Usage

posts = Post.includes(:user).recent.limit(10) recent_comments = Comment.where(post_id: post.id).order(created_at: :desc).limit(5)

undefined

posts = Post.includes(:user).recent.limit(10) recent_comments = Comment.where(post_id: post.id).order(created_at: :desc).limit(5)

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7. Serializers

7. 序列化器

ruby

undefined

ruby

undefined

app/serializers/user_serializer.rb

class UserSerializer def initialize(user) @user = user end

def to_json { id: @user.id, email: @user.email, first_name: @user.first_name, last_name: @user.last_name, full_name: @user.full_name, role: @user.role, is_active: @user.is_active, created_at: @user.created_at.iso8601, updated_at: @user.updated_at.iso8601 } end end

class UserSerializer def initialize(user) @user = user end

def to_json { id: @user.id, email: @user.email, first_name: @user.first_name, last_name: @user.last_name, full_name: @user.full_name, role: @user.role, is_active: @user.is_active, created_at: @user.created_at.iso8601, updated_at: @user.updated_at.iso8601 } end end

In controller

def show render json: UserSerializer.new(@user).to_json end

undefined

def show render json: UserSerializer.new(@user).to_json end

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Best Practices

最佳实践

✅ DO

✅ 建议

Use conventions over configuration
Leverage Active Record associations
Implement proper scopes for queries
Use strong parameters for security
Implement authentication in ApplicationController
Use services for complex business logic
Implement proper error handling
Use database migrations for schema changes
Validate all inputs at model level
Use before_action filters appropriately

遵循"约定优于配置"原则
充分利用Active Record关联
为查询实现合适的作用域
使用强参数保障安全
在ApplicationController中实现身份验证
使用服务层处理复杂业务逻辑
实现完善的错误处理
使用数据库迁移管理Schema变更
在模型层验证所有输入
合理使用before_action过滤器

❌ DON'T

❌ 禁忌

Use raw SQL without parameterization
Implement business logic in controllers
Trust user input without validation
Store secrets in code
Use select * without specifying columns
Forget N+1 query problems (use includes/joins)
Implement authentication in each controller
Use global variables
Ignore database constraints

使用未参数化的原生SQL
在控制器中实现业务逻辑
信任未经过验证的用户输入
在代码中存储敏感信息
使用select *而不指定列
忽略N+1查询问题（使用includes/joins解决）
在每个控制器中单独实现身份验证
使用全局变量
忽略数据库约束

Complete Example

完整示例

ruby

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ruby

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Gemfile

source 'https://rubygems.org' gem 'rails', '~~> 7.0.0' gem 'pg', '~~> 1.1' gem 'bcrypt', '~> 3.1.7' gem 'jwt' gem 'kaminari'

models.rb + controllers.rb (see sections above)

routes.rb and migrations (see sections above)

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",

ruby-rails-application

Original

Translation

Ruby Rails Application

Ruby on Rails 应用程序

Overview

概述

When to Use

适用场景

Instructions

操作步骤

1. Rails Project Setup

1. Rails 项目搭建

2. Models with Active Record

2. 基于Active Record的模型

app/models/user.rb

app/models/user.rb

app/models/post.rb

app/models/post.rb

app/models/comment.rb

app/models/comment.rb

3. Database Migrations

3. 数据库迁移

db/migrate/20240101120000_create_users.rb

db/migrate/20240101120000_create_users.rb

db/migrate/20240101120001_create_posts.rb

db/migrate/20240101120001_create_posts.rb

db/migrate/20240101120002_create_comments.rb

db/migrate/20240101120002_create_comments.rb

4. Controllers with RESTful Actions

4. 带RESTful动作的控制器

app/controllers/api/v1/users_controller.rb

app/controllers/api/v1/users_controller.rb

app/controllers/api/v1/posts_controller.rb

app/controllers/api/v1/posts_controller.rb

5. Authentication with JWT

5. 基于JWT的身份验证

app/controllers/application_controller.rb

app/controllers/application_controller.rb

config/routes.rb

config/routes.rb

6. Active Record Queries

6. Active Record 查询

app/services/post_service.rb

app/services/post_service.rb

Usage

Usage

7. Serializers

7. 序列化器

app/serializers/user_serializer.rb

app/serializers/user_serializer.rb

In controller

In controller

Best Practices

最佳实践

✅ DO

✅ 建议

❌ DON'T

❌ 禁忌

Complete Example

完整示例

Gemfile

Gemfile

models.rb + controllers.rb (see sections above)

models.rb + controllers.rb (see sections above)

routes.rb and migrations (see sections above)

routes.rb and migrations (see sections above)