Replace IRespondToRequests with PSR-7 ResponseInterface

src/Capabilities/ICanCreateResponses.php

@@ -3,9 +3,24 @@
 namespace Friendica\Capabilities;
 
 use Friendica\Network\HTTPException\InternalServerErrorException;
+use Psr\Http\Message\ResponseInterface;
 
-interface ICanCreateResponses extends IRespondToRequests
+interface ICanCreateResponses
 {
+	const TYPE_HTML = 'html';
+	const TYPE_XML  = 'xml';
+	const TYPE_JSON = 'json';
+	const TYPE_ATOM = 'atom';
+	const TYPE_RSS  = 'rss';
+
+	const ALLOWED_TYPES = [
+		self::TYPE_HTML,
+		self::TYPE_XML,
+		self::TYPE_JSON,
+		self::TYPE_ATOM,
+		self::TYPE_RSS
+	];
+
 	/**
 	 * Adds a header entry to the module response
 	 *
@@ -30,4 +45,12 @@ interface ICanCreateResponses extends IRespondToRequests
 	 * @throws InternalServerErrorException
 	 */
 	public function setType(string $type, ?string $content_type = null): void;
+
+	/**
+	 * Creates a PSR-7 compliant interface
+	 * @see https://www.php-fig.org/psr/psr-7/
+	 *
+	 * @return ResponseInterface
+	 */
+	public function generate(): ResponseInterface;
 }