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diff --git a/www/wiki/includes/linkeddata/PageDataRequestHandler.php b/www/wiki/includes/linkeddata/PageDataRequestHandler.php
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+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
+
+use Wikimedia\Http\HttpAcceptParser;
+use Wikimedia\Http\HttpAcceptNegotiator;
+
+/**
+ * Request handler implementing a data interface for mediawiki pages.
+ *
+ * @author Daniel Kinzler
+ * @author Amir Sarabadanai
+ */
+class PageDataRequestHandler {
+
+	/**
+	 * Checks whether the request is complete, i.e. whether it contains all information needed
+	 * to reply with page data.
+	 *
+	 * This does not check whether the request is valid and will actually produce a successful
+	 * response.
+	 *
+	 * @param string|null $subPage
+	 * @param WebRequest $request
+	 *
+	 * @return bool
+	 * @throws HttpError
+	 */
+	public function canHandleRequest( $subPage, WebRequest $request ) {
+		if ( $subPage === '' || $subPage === null ) {
+			if ( $request->getText( 'target', '' ) === '' ) {
+				return false;
+			} else {
+				return true;
+			}
+		}
+
+		$parts = explode( '/', $subPage, 2 );
+		if ( $parts !== 2 ) {
+			$slot = $parts[0];
+			if ( $slot === 'main' || $slot === '' ) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+	/**
+	 * Main method for handling requests.
+	 *
+	 * @param string $subPage
+	 * @param WebRequest $request The request parameters. Known parameters are:
+	 *        - title: the page title
+	 *        - format: the format
+	 *        - oldid|revision: the revision ID
+	 * @param OutputPage $output
+	 *
+	 * @note: Instead of an output page, a WebResponse could be sufficient, but
+	 *        redirect logic is currently implemented in OutputPage.
+	 *
+	 * @throws HttpError
+	 */
+	public function handleRequest( $subPage, WebRequest $request, OutputPage $output ) {
+		// No matter what: The response is always public
+		$output->getRequest()->response()->header( 'Access-Control-Allow-Origin: *' );
+
+		if ( !$this->canHandleRequest( $subPage, $request ) ) {
+			throw new HttpError( 400, wfMessage( 'pagedata-bad-title', $subPage ) );
+		}
+
+		$revision = 0;
+
+		$parts = explode( '/', $subPage, 2 );
+		if ( $subPage !== '' ) {
+			$title = $parts[1];
+		} else {
+			$title = $request->getText( 'target', '' );
+		}
+
+		$revision = $request->getInt( 'oldid', $revision );
+		$revision = $request->getInt( 'revision', $revision );
+
+		if ( $title === null || $title === '' ) {
+			//TODO: different error message?
+			throw new HttpError( 400, wfMessage( 'pagedata-bad-title', $title ) );
+		}
+
+		try {
+			$title = Title::newFromTextThrow( $title );
+		} catch ( MalformedTitleException $ex ) {
+			throw new HttpError( 400, wfMessage( 'pagedata-bad-title', $title ) );
+		}
+
+		$this->httpContentNegotiation( $request, $output, $title, $revision );
+	}
+
+	/**
+	 * Applies HTTP content negotiation.
+	 * If the negotiation is successful, this method will set the appropriate redirect
+	 * in the OutputPage object and return. Otherwise, an HttpError is thrown.
+	 *
+	 * @param WebRequest $request
+	 * @param OutputPage $output
+	 * @param Title $title
+	 * @param int $revision The desired revision
+	 *
+	 * @throws HttpError
+	 */
+	public function httpContentNegotiation(
+		WebRequest $request,
+		OutputPage $output,
+		Title $title,
+		$revision = 0
+	) {
+		$contentHandler = ContentHandler::getForTitle( $title );
+		$mimeTypes = $contentHandler->getSupportedFormats();
+
+		$headers = $request->getAllHeaders();
+		if ( isset( $headers['ACCEPT'] ) ) {
+			$parser = new HttpAcceptParser();
+			$accept = $parser->parseWeights( $headers['ACCEPT'] );
+		} else {
+			// anything goes
+			$accept = [
+				'*' => 0.1 // just to make extra sure
+			];
+			// prefer the default
+			$accept[$mimeTypes[0]] = 1;
+		}
+
+		$negotiator = new HttpAcceptNegotiator( $mimeTypes );
+		$format = $negotiator->getBestSupportedKey( $accept, null );
+
+		if ( $format === null ) {
+			$format = isset( $accept['text/html'] ) ? 'text/html' : null;
+		}
+
+		if ( $format === null ) {
+			$msg = wfMessage( 'pagedata-not-acceptable', implode( ', ', $mimeTypes ) );
+			throw new HttpError( 406, $msg );
+		}
+
+		$url = $this->getDocUrl( $title, $format, $revision );
+		$output->redirect( $url, 303 );
+	}
+
+	/**
+	 * Returns a url representing the given title.
+	 *
+	 * @param Title $title
+	 * @param string|null $format The (normalized) format name, or ''
+	 * @param int $revision
+	 * @return string
+	 */
+	private function getDocUrl( Title $title, $format = '', $revision = 0 ) {
+		$params = [];
+
+		if ( $revision > 0 ) {
+			$params['oldid'] = $revision;
+		}
+
+		if ( $format === 'text/html' ) {
+			return $title->getFullURL( $params );
+		}
+
+		$params[ 'action' ] = 'raw';
+
+		return $title->getFullURL( $params );
+	}
+
+}