? ??? ?? ?????? ??? ????? YII? ?? ??? ?? ??? ?????. ?? ?? ?? (? : ??, URLManager, ????, ??)? ??? ???? ??? ?? ?? (??? ???, ??, ????)? ?????. ??

YII? ???? ??? ?? ??? ??? ??????

YII? ?? ??? ????? ??? ???????. It begins with the entry script, typically index.php , which bootstraps the application. This involves creating an application instance, configuring it based on the application configuration file ( config/web.php or similar), and initiating the request. ?? ?? ??????? ?? ?? ??? ???? ?? ??? (GET, POST ?), ?? ? URL ? ?? ? ???? ?????.

???? ?? ????? URL ???? ???? URL? ?? ???? ??? ?? ???? ???? ? ??? ?????. ???? ?? ? ??? URL? ???? ?? ?????. ??? ???? ?? ???? ??? ?????. ???? ??? ????? ???? ????? ???? ?? ??? ?? ???? ??? ??? ?????. ? ??? ??, ????? ??????.

????? ??? ? ??? HTTP ???? ????? (????)? ?? ?????. ?? ?????? ??? ???? ??? ?? ? ??? ???? ??? ??? ? ??? ?????. ?? ??? ???? ??? ???? ?? ?? ??? ?? ??? ??? ?????. ? ????? ????? ??? ?? ????? YII? ??? ?? ?? ??? ?? ???? ???? ? ??? ???? ???? ??? ?????.

YII? ?? ?? ????? ??? ?? ?? ??? ??????

? ?? ?? ?? ??? YII? ?? ?? ????? ??????.

• Yii::$app (Application): The central component, managing the entire application lifecycle. ??? ???? ?? ?? ??? ?? ???? ?????.
• \yii\web\Request : This component parses the incoming HTTP request, providing information about the request method, URL, headers, and submitted data.
• \yii\web\UrlManager : This component maps incoming URLs to controller actions and vice-versa. ?? ????? ??? ???? ??? ??? ? ??? ????.
• \yii\base\Controller : Controllers handle requests and interact with models. ?? ??? ???? ??? ???? ????.
• \yii\base\Action : Actions are methods within controllers that execute specific tasks in response to a request.
• \yii\web\Response : This component is responsible for sending the HTTP response back to the client. ??, ?? ? ?? ?? (????? ??? ???)? ?????.
• \yii\web\View : This component renders views, which are the templates that generate the HTML output sent to the client. ??? ??? ? ?? ??? ?????.
• Filters (Behaviors): These allow for adding pre- and post-processing logic to controllers and actions, providing hooks for tasks like authentication, authorization, and logging.

?? ??? ?? YII? ?? ?? ??? ??? ??? ????? ????? ?????????

YII? ?? ?? ??? ??? ??? ???? ?????? ? ?? ????? ?????.

• Creating custom controllers and actions: This allows you to implement specific logic to handle particular requests.
• Using event handlers: Yii's components emit events at various stages of the request processing lifecycle. ??? ???? ??? ???? ???? ??? ?? ??? ?? ??? ? ????. For instance, you can listen to the beforeAction event of a controller to perform authentication checks before the action executes.
• Implementing custom filters (behaviors): Behaviors can add functionality to controllers and actions without modifying their core code. ??? ??, ?? ?? ??? ?? ??? ?? ???? ? ?????.
• Overriding default components: You can replace Yii's default components with custom implementations. ?? ?? ??? ??? ??? ?? ??? ? ????. For example, you might create a custom UrlManager to implement a more complex routing scheme.
• Using middleware: (In Yii2 Advanced Application) Middleware provides a powerful mechanism to intercept requests and responses, allowing you to perform tasks such as logging, authentication, and request transformation before the request reaches the application.

YII? ?? ???? ???? ?? ?? ??? ???? ??? ??? ? ? ?????

YII? ?? ???? ? ?? ??? ?? ?? ???? ??? ? ????.

• Database queries: Inefficient database queries are a common culprit. ??? ???, ?? (? : Activerecord ?? ?? Redis? ?? ?? ?? ??? ??)? ???? ??? ????? ?? ?? ???????. ???? ? ??? ???? ?? ??? ??????.
• Slow view rendering: Complex or inefficient views can slow down rendering. ?? ?? ??? ?????? ?? ?? ????? ?? ????? ???? ???? ??? ??? ??????? ???????.
• Inefficient caching: Improperly configured or underutilized caching can negate its benefits. ?? ??? ? ???? ????? ???? ??? ??????.
• Excessive use of extensions: While extensions enhance functionality, poorly written or inefficient extensions can negatively impact performance. ??? ???? ???? ??? ??? ??????.
• Lack of code optimization: Poorly written or unoptimized code can lead to performance problems. ???? ? ??? ???? ???? ?? ??? ???? ?? ?? ???????.

??? ?? :

• Profiling: Use Yii's profiling tools or other profiling tools (like Xdebug) to pinpoint performance bottlenecks.
• Caching: Implement caching strategies for database queries, view rendering, and other frequently accessed data.
• Database optimization: Optimize database queries and schema design. ??? ??? ???? ?????? ?? ??? ??????.
• Code optimization: Refactor inefficient code and use appropriate algorithms and data structures.
• Asset optimization: Minimize and combine CSS and JavaScript files to reduce HTTP requests.
• Load balancing and server upgrades: For high-traffic applications, consider load balancing and upgrading server hardware.

??? ??? ? ?? ??? ???? ??? ??? ??? ?????? YII ?? ????? ??? ?? ???? ? ????.

? ??? YII? ???? ??? ?? ??? ??? ??????? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!