Example PSR-15 Middleware for TYPO3 v13

This middleware demonstrates the implementation of a PSR-15 middleware in TYPO3 v13 with complete PHPDoc documentation for automatic documentation generation.

The middleware adds a custom header to every response and can intercept and specially handle API requests.

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• Full name: \Vendor\ExtensionSkeleton\Middleware\ExampleMiddleware
• This class implements: MiddlewareInterface, LoggerAwareInterface

See Also:

• https://docs.typo3.org/m/typo3/reference-coreapi/main/en-us/ApiOverview/RequestHandling/Index.html

Constants

Constant	Visibility	Type	Value
CUSTOM_HEADER	private		'X-Extension-Skeleton'
API_PATH_PREFIX	private		'/api/skeleton/'

Methods

process

Processes an incoming server request

public process(\Psr\Http\Message\ServerRequestInterface $request, \Psr\Http\Server\RequestHandlerInterface $handler): \Psr\Http\Message\ResponseInterface

This method is called for every request and allows you to modify the request or return an early response.

Functionality:

• Checks if it's an API request
• Adds custom header to the response
• Logs request information

Parameters:

Parameter	Type	Description
$request	\Psr\Http\Message\ServerRequestInterface	The incoming HTTP request
$handler	\Psr\Http\Server\RequestHandlerInterface	The next request handler in the chain

Return Value:

The HTTP response

Throws:

If request processing fails

• RuntimeException

See Also:

• \Vendor\ExtensionSkeleton\Middleware\process() - is automatically called by TYPO3's middleware stack

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isApiRequest

Checks if this is an API request

private isApiRequest(string $path): bool

A request is treated as an API request if the path starts with the defined API_PATH_PREFIX.

Parameters:

Parameter	Type	Description
$path	string	The request path

Return Value:

True if it's an API request, false otherwise

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handleApiRequest

Handles special API requests

private handleApiRequest(\Psr\Http\Message\ServerRequestInterface $request): \Psr\Http\Message\ResponseInterface

This method is only called for requests that start with the API_PATH_PREFIX. It returns a JSON response.

Parameters:

Parameter	Type	Description
$request	\Psr\Http\Message\ServerRequestInterface	The API request

Return Value:

JSON response with API data

Throws:

If API processing fails

• RuntimeException

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