# Debug Extension for Yii 2
This extension provides a debugger for Yii 2 applications. When this extension is used, a debugger toolbar will appear at the bottom of every page. The extension also provides a set of standalone pages to display more detailed debug information.
The toolbar displays information about the currently opened page, while the debugger can be used to analyze data you've previously collected (i.e., to confirm the values of variables).
Out of the box these tools allow you to:
* quickly get the framework version, PHP version, response status, current controller and action, performance info and more via toolbar;
* browse the application and PHP configuration;
* view the request data, request and response headers, session data, and environment variables;
* see, search, and filter the logs;
* view any profiling results;
* view the database queries executed by the page;
* view the emails sent by the application.
All of this information will be available per request, allowing you to revisit the information for past requests as well.
## [](https://github.com/yiisoft/yii2-debug/blob/master/docs/guide/README.md#getting-started)Getting Started
* [Installation](https://github.com/yiisoft/yii2-debug/blob/master/docs/guide/installation.md)
* **TBD** [Basic Usage](https://github.com/yiisoft/yii2-debug/blob/master/docs/guide/basic-usage.md)
## [](https://github.com/yiisoft/yii2-debug/blob/master/docs/guide/README.md#additional-topics)Additional topics
* [Creating your own panels](https://github.com/yiisoft/yii2-debug/blob/master/docs/guide/topics-creating-your-own-panels.md)
- 介绍(Introduction)
- 关于 Yii(About Yii)
- 从 Yii 1.1 升级(Upgrading from Version 1.1)
- 入门(Getting Started)
- 安装 Yii(Installing Yii)
- 运行应用(Running Applications)
- 第一次问候(Saying Hello)
- 使用 Forms(Working with Forms)
- 玩转 Databases(Working with Databases)
- 用 Gii 生成代码(Generating Code with Gii)
- 更上一层楼(Looking Ahead)
- 应用结构(Application Structure)
- 结构概述(Overview)
- 入口脚本(Entry Scripts)
- 应用(Applications)
- 应用组件(Application Components)
- 控制器(Controllers)
- 模型(Models)
- 视图(Views)
- 模块(Modules)
- 过滤器(Filters)
- 小部件(Widgets)
- 前端资源(Assets)
- 扩展(Extensions)
- 请求处理(Handling Requests)
- 运行概述(Overview)
- 引导(Bootstrapping)
- 路由引导与创建 URL(Routing and URL Creation)
- 请求(Requests)
- 响应(Responses)
- Sessions and Cookies
- 错误处理(Handling Errors)
- 日志(Logging)
- 关键概念(Key Concepts)
- 组件(Components)
- 属性(Properties)
- 事件(Events)
- 行为(Behaviors)
- 配置(Configurations)
- 别名(Aliases)
- 类自动加载(Class Autoloading)
- 服务定位器(Service Locator)
- 依赖注入容器(Dependency Injection Container)
- 配合数据库工作(Working with Databases)
- 数据库访问(Data Access Objects): 数据库连接、基本查询、事务和模式操作
- 查询生成器(Query Builder): 使用简单抽象层查询数据库
- 活动记录(Active Record): 活动记录对象关系映射(ORM),检索和操作记录、定义关联关系
- 数据库迁移(Migrations): 在团体开发中对你的数据库使用版本控制
- Sphinx
- Redis
- MongoDB
- ElasticSearch
- 接收用户数据(Getting Data from Users)
- 创建表单(Creating Forms)
- 输入验证(Validating Input)
- 文件上传(Uploading Files)
- 收集列表输入(Collecting Tabular Input)
- 多模型同时输入(Getting Data for Multiple Models)
- 显示数据(Displaying Data)
- 格式化输出数据(Data Formatting)
- 分页(Pagination)
- 排序(Sorting)
- 数据提供器(Data Providers)
- 数据小部件(Data Widgets)
- 操作客户端脚本(Working with Client Scripts)
- 主题(Theming)
- 安全(Security)
- 认证(Authentication)
- 授权(Authorization)
- 处理密码(Working with Passwords)
- 客户端认证(Auth Clients)
- 安全领域的最佳实践(Best Practices)
- 缓存(Caching)
- 概述(Overview)
- 数据缓存(Data Caching)
- 片段缓存(Fragment Caching)
- 分页缓存(Page Caching)
- HTTP 缓存(HTTP Caching)
- RESTful Web 服务
- 快速入门(Quick Start)
- 资源(Resources)
- 控制器(Controllers)
- 路由(Routing)
- 格式化响应(Response Formatting)
- 授权验证(Authentication)
- 速率限制(Rate Limiting)
- 版本化(Versioning)
- 错误处理(Error Handling)
- 开发工具(Development Tools)
- 调试工具栏和调试器(Debug Toolbar and Debugger)
- 使用 Gii 生成代码(Generating Code using Gii)
- TBD 生成 API 文档(Generating API Documentation)
- 测试(Testing)
- 概述(Overview)
- 搭建测试环境(Testing environment setup)
- 单元测试(Unit Tests)
- 功能测试(Functional Tests)
- 验收测试(Acceptance Tests)
- 测试夹具(Fixtures)
- 高级专题(Special Topics)
- 高级应用模版(Advanced Project Template)
- 从头构建自定义模版(Building Application from Scratch)
- 控制台命令(Console Commands)
- 核心验证器(Core Validators)
- 国际化(Internationalization)
- 收发邮件(Mailing)
- 性能优化(Performance Tuning)
- 共享主机环境(Shared Hosting Environment)
- 模板引擎(Template Engines)
- 集成第三方代码(Working with Third-Party Code)
- 小部件(Widgets)
- Bootstrap 小部件(Bootstrap Widgets)
- jQuery UI 小部件(jQuery UI Widgets)
- 助手类(Helpers)
- 助手一览(Overview)
- Array 助手(ArrayHelper)
- Html 助手(Html)
- Url 助手(Url)