Merge "Revert "Re-apply "Use parsoid directly in /page/html handler"""

5 files changed, 106 insertions, 173 deletions

diff --git a/includes/Rest/Handler/LatestPageContentHandler.php b/includes/Rest/Handler/LatestPageContentHandler.php
index d0d4add787fc..491386478609 100644
--- a/includes/Rest/Handler/LatestPageContentHandler.php
+++ b/includes/Rest/Handler/LatestPageContentHandler.php
@@ -82,7 +82,7 @@ abstract class LatestPageContentHandler extends SimpleHandler {
 		if ( $this->latestRevision === null ) {
 			$title = $this->getTitle();
 			if ( $title && $title->getArticleID() ) {
-				$this->latestRevision = $this->revisionLookup->getRevisionByTitle( $title );
+				$this->latestRevision = $this->revisionLookup->getKnownCurrentRevision( $title );
 			} else {
 				$this->latestRevision = false;
 			}
diff --git a/includes/Rest/Handler/PageHTMLHandler.php b/includes/Rest/Handler/PageHTMLHandler.php
index aa510d6e7630..7f24c22ee02e 100644
--- a/includes/Rest/Handler/PageHTMLHandler.php
+++ b/includes/Rest/Handler/PageHTMLHandler.php
@@ -3,27 +3,23 @@
 namespace MediaWiki\Rest\Handler;
 
 use Config;
+use ConfigException;
+use Exception;
+use GuzzleHttp\Psr7\Uri;
 use LogicException;
 use MediaWiki\Linker\LinkTarget;
-use MediaWiki\MediaWikiServices;
-use MediaWiki\Page\WikiPageFactory;
-use MediaWiki\Parser\ParserCacheFactory;
 use MediaWiki\Permissions\PermissionManager;
 use MediaWiki\Rest\LocalizedHttpException;
 use MediaWiki\Rest\Response;
-use MediaWiki\Rest\ResponseInterface;
 use MediaWiki\Rest\StringStream;
 use MediaWiki\Revision\RevisionLookup;
-use ParserCache;
-use ParserOptions;
-use ParserOutput;
+use RestbaseVirtualRESTService;
 use TitleFactory;
 use TitleFormatter;
+use UIDGenerator;
+use VirtualRESTServiceClient;
+use WebRequest;
 use Wikimedia\Message\MessageValue;
-use Wikimedia\Parsoid\Config\PageConfig;
-use Wikimedia\Parsoid\Core\ClientError;
-use Wikimedia\Parsoid\Core\ResourceLimitExceededException;
-use Wikimedia\Parsoid\Parsoid;
 
 /**
  * A handler that returns Parsoid HTML for the following routes:
@@ -39,23 +35,27 @@ use Wikimedia\Parsoid\Parsoid;
 class PageHTMLHandler extends LatestPageContentHandler {
 	private const MAX_AGE_200 = 5;
 
-	/** @var ParserCache */
-	private $parserCache;
+	/** @var VirtualRESTServiceClient */
+	private $restClient;
 
-	/** @var WikiPageFactory */
-	private $wikiPageFactory;
-
-	/** @var Parsoid|null */
-	private $parsoid;
+	/** @var array */
+	private $htmlResponse;
 
+	/**
+	 * @param Config $config
+	 * @param PermissionManager $permissionManager
+	 * @param RevisionLookup $revisionLookup
+	 * @param TitleFormatter $titleFormatter
+	 * @param TitleFactory $titleFactory
+	 * @param VirtualRESTServiceClient $virtualRESTServiceClient
+	 */
 	public function __construct(
 		Config $config,
 		PermissionManager $permissionManager,
 		RevisionLookup $revisionLookup,
 		TitleFormatter $titleFormatter,
 		TitleFactory $titleFactory,
-		ParserCacheFactory $parserCacheFactory,
-		WikiPageFactory $wikiPageFactory
+		VirtualRESTServiceClient $virtualRESTServiceClient
 	) {
 		parent::__construct(
 			$config,
@@ -64,33 +64,72 @@ class PageHTMLHandler extends LatestPageContentHandler {
 			$titleFormatter,
 			$titleFactory
 		);
-		$this->parserCache = $parserCacheFactory->getInstance( 'parsoid' );
-		$this->wikiPageFactory = $wikiPageFactory;
+
+		$this->restClient = $virtualRESTServiceClient;
 	}
 
 	/**
 	 * @param LinkTarget $title
-	 * @return string
+	 * @return array
+	 * @throws LocalizedHttpException
 	 */
-	private function constructHtmlUrl( LinkTarget $title ): string {
-		return $this->getRouter()->getRouteUrl( '/v1/page/{title}/html', [ 'title' => $title ] );
+	private function fetchHtmlFromRESTBase( LinkTarget $title ): array {
+		if ( $this->htmlResponse !== null ) {
+			return $this->htmlResponse;
+		}
+
+		list( , $service ) = $this->restClient->getMountAndService( '/restbase/ ' );
+		if ( !$service ) {
+			try {
+				$restConfig = $this->config->get( 'VirtualRestConfig' );
+				if ( !isset( $restConfig['modules']['restbase'] ) ) {
+					throw new ConfigException(
+						__CLASS__ . " requires restbase module configured for VirtualRestConfig"
+					);
+				}
+				$this->restClient->mount( '/restbase/',
+					new RestbaseVirtualRESTService( $restConfig['modules']['restbase'] ) );
+			} catch ( Exception $e ) {
+				// This would usually be config exception, but let's fail on any exception
+				throw new LocalizedHttpException( MessageValue::new( 'rest-html-backend-error' ), 500 );
+			}
+		}
+
+		$this->htmlResponse = $this->restClient->run( [
+			'method' => 'GET',
+			'url' => '/restbase/local/v1/page/html/' .
+				urlencode( $this->titleFormatter->getPrefixedDBkey( $title ) ) .
+				'?redirect=false'
+		] );
+		return $this->htmlResponse;
 	}
 
 	/**
-	 * Sets the 'Cache-Control' header no more then provided $expiry.
-	 * @param ResponseInterface $response
-	 * @param int|null $expiry
+	 * @param LinkTarget $title
+	 * @return array
+	 * @throws LocalizedHttpException
 	 */
-	private function setCacheControl( ResponseInterface $response, int $expiry = null ) {
-		if ( $expiry === null ) {
-			$maxAge = self::MAX_AGE_200;
-		} else {
-			$maxAge = min( self::MAX_AGE_200, $expiry );
+	private function fetch200HtmlFromRESTBase( LinkTarget $title ): array {
+		$restbaseResp = $this->fetchHtmlFromRESTBase( $title );
+		if ( $restbaseResp['code'] !== 200 ) {
+			throw new LocalizedHttpException(
+				MessageValue::new( 'rest-html-backend-error' ),
+				$restbaseResp['code']
+			);
 		}
-		$response->setHeader(
-			'Cache-Control',
-			'max-age=' . $maxAge
-		);
+		return $restbaseResp;
+	}
+
+	/**
+	 * @return string
+	 */
+	private function constructHtmlUrl(): string {
+		$wr = new WebRequest();
+		$urlParts = wfParseUrl( $wr->getFullRequestURL() );
+		$currentPathParts = explode( '/', $urlParts['path'] );
+		$currentPathParts[ count( $currentPathParts ) - 1 ] = 'html';
+		$urlParts['path'] = implode( '/', $currentPathParts );
+		return Uri::fromParts( $urlParts );
 	}
 
 	/**
@@ -126,29 +165,26 @@ class PageHTMLHandler extends LatestPageContentHandler {
 		switch ( $htmlType ) {
 			case 'bare':
 				$body = $this->constructMetadata( $titleObj, $revision );
-				$body['html_url'] = $this->constructHtmlUrl( $titleObj );
+				$body['html_url'] = $this->constructHtmlUrl();
 				$response = $this->getResponseFactory()->createJson( $body );
-				$this->setCacheControl( $response );
 				break;
 			case 'html':
-				$parserOutput = $this->getHtmlFromCache( $titleObj );
+				$restbaseResp = $this->fetch200HtmlFromRESTBase( $titleObj );
 				$response = $this->getResponseFactory()->create();
-				// TODO: need to respect content-type returned by Parsoid.
-				$response->setHeader( 'Content-Type', 'text/html' );
-				$this->setCacheControl( $response, $parserOutput->getCacheExpiry() );
-				$response->setBody( new StringStream( $parserOutput->getText() ) );
+				$response->setHeader( 'Content-Type', $restbaseResp[ 'headers' ][ 'content-type' ] );
+				$response->setBody( new StringStream( $restbaseResp[ 'body' ] ) );
 				break;
 			case 'with_html':
-				$parserOutput = $this->getHtmlFromCache( $titleObj );
+				$restbaseResp = $this->fetch200HtmlFromRESTBase( $titleObj );
 				$body = $this->constructMetadata( $titleObj, $revision );
-				$body['html'] = $parserOutput->getText();
+				$body['html'] = $restbaseResp['body'];
 				$response = $this->getResponseFactory()->createJson( $body );
-				$this->setCacheControl( $response, $parserOutput->getCacheExpiry() );
 				break;
 			default:
 				throw new LogicException( "Unknown HTML type $htmlType" );
 		}
 
+		$response->setHeader( 'Cache-Control', 'max-age=' . self::MAX_AGE_200 );
 		return $response;
 	}
 
@@ -157,6 +193,7 @@ class PageHTMLHandler extends LatestPageContentHandler {
 	 * if the latest revision of a page has been made private, un-readable for another reason,
 	 * or a newer revision exists.
 	 * @return string|null
+	 * @throws LocalizedHttpException
 	 */
 	protected function getETag(): ?string {
 		$title = $this->getTitle();
@@ -166,141 +203,42 @@ class PageHTMLHandler extends LatestPageContentHandler {
 		if ( $this->getHtmlType() === 'bare' ) {
 			return '"' . $this->getLatestRevision()->getId() . '"';
 		}
-		// While we are not differentiating the output by parser options and
-		// only provide anon parses, cache time or page touched provides a good
-		// reference for etag. Once we start doing non-anon parses, this needs
-		// to start incorporating current users ParserOptions.
-		return '"' . $this->getLastModified() . '"';
+
+		$restbaseRes = $this->fetch200HtmlFromRESTBase( $title );
+		return $restbaseRes['headers']['etag'] ?? null;
 	}
 
 	/**
 	 * @return string|null
+	 * @throws LocalizedHttpException
 	 */
 	protected function getLastModified(): ?string {
 		$title = $this->getTitle();
 		if ( !$title || !$title->getArticleID() || !$this->isAccessible( $title ) ) {
 			return null;
 		}
+
 		if ( $this->getHtmlType() === 'bare' ) {
 			return $this->getLatestRevision()->getTimestamp();
 		}
-		$wikiPage = $this->wikiPageFactory->newFromTitle( $title );
-		// The cache time of the metadata belongs to the ParserOutput
-		// variant cached last. While we are not differentiating the
-		// parser options, it's fine. Once we start supporting non-anon
-		// parses, we would need to fetch the actual ParserOutput to find
-		// out it's cache time.
-		$cacheMetadata = $this->parserCache->getMetadata(
-			$wikiPage,
-			ParserCache::USE_CURRENT_ONLY
-		);
-		if ( $cacheMetadata ) {
-			return $cacheMetadata->getCacheTime();
-		} else {
-			return $wikiPage->getTouched();
-		}
-	}
-
-	private function getHtmlType(): string {
-		return $this->getConfig()['format'];
-	}
 
-	/**
-	 * Assert that Parsoid services are available.
-	 * TODO: once parsoid glue services are in core,
-	 * this will become a no-op and will be removed.
-	 * See T265518
-	 * @throws LocalizedHttpException
-	 */
-	private function assertParsoidInstalled() {
-		$services = MediaWikiServices::getInstance();
-		if ( $services->has( 'ParsoidSiteConfig' ) &&
-			$services->has( 'ParsoidPageConfigFactory' ) &&
-			$services->has( 'ParsoidDataAccess' ) ) {
-			return;
+		$restbaseRes = $this->fetch200HtmlFromRESTBase( $title );
+		$restbaseEtag = $restbaseRes['headers']['etag'] ?? null;
+		if ( !$restbaseEtag ) {
+			return null;
 		}
-		throw new LocalizedHttpException(
-			MessageValue::new( 'rest-html-backend-error' ), 501 );
-	}
 
-	/**
-	 * @return Parsoid
-	 * @throws LocalizedHttpException
-	 */
-	protected function createParsoid(): Parsoid {
-		$this->assertParsoidInstalled();
-		if ( $this->parsoid === null ) {
-			// TODO: once parsoid glue services are in core,
-			// this will need to use normal DI.
-			// See T265518
-			$services = MediaWikiServices::getInstance();
-			$this->parsoid = new Parsoid(
-				$services->get( 'ParsoidSiteConfig' ),
-				$services->get( 'ParsoidDataAccess' )
-			);
+		$etagComponents = [];
+		if ( !preg_match( '/^(?:W\/)?"?[^"\/]+(?:\/([^"\/]+))"?$/',
+			$restbaseEtag, $etagComponents )
+		) {
+			return null;
 		}
-		return $this->parsoid;
-	}
-
-	/**
-	 * @param LinkTarget $linkTarget
-	 * @return PageConfig
-	 * @throws LocalizedHttpException
-	 */
-	private function createPageConfig(
-		LinkTarget $linkTarget
-	): PageConfig {
-		$this->assertParsoidInstalled();
-		// Currently everything is parsed as anon since Parsoid
-		// can't report the used options.
-		// Already checked that title/revision exist and accessible.
-		return MediaWikiServices::getInstance()
-			->get( 'ParsoidPageConfigFactory' )
-			->create( $linkTarget );
-	}
 
-	/**
-	 * @param LinkTarget $title
-	 * @return ParserOutput a tuple with html and content-type
-	 * @throws LocalizedHttpException
-	 */
-	private function getHtmlFromCache( LinkTarget $title ): ParserOutput {
-		$wikiPage = $this->wikiPageFactory->newFromLinkTarget( $title );
-		$parserOutput = $this->parserCache->get( $wikiPage, ParserOptions::newFromAnon() );
-		if ( $parserOutput ) {
-			return $parserOutput;
-		}
-		$fakeParserOutput = $this->parse( $title );
-		$this->parserCache->save( $fakeParserOutput, $wikiPage, ParserOptions::newFromAnon() );
-		return $fakeParserOutput;
+		return UIDGenerator::getTimestampFromUUIDv1( $etagComponents[1] ) ?: null;
 	}
 
-	/**
-	 * @param LinkTarget $title
-	 * @return ParserOutput
-	 * @throws LocalizedHttpException
-	 */
-	private function parse( LinkTarget $title ): ParserOutput {
-		$parsoid = $this->createParsoid();
-		$pageConfig = $this->createPageConfig( $title );
-		try {
-			$pageBundle = $parsoid->wikitext2html( $pageConfig, [
-				'discardDataParsoid' => true,
-				'pageBundle' => true,
-			] );
-			return new ParserOutput( $pageBundle->html );
-		} catch ( ClientError $e ) {
-			throw new LocalizedHttpException(
-				MessageValue::new( 'rest-html-backend-error' ),
-				400,
-				[ 'reason' => $e->getMessage() ]
-			);
-		} catch ( ResourceLimitExceededException $e ) {
-			throw new LocalizedHttpException(
-				MessageValue::new( 'rest-resource-limit-exceeded' ),
-				413,
-				[ 'reason' => $e->getMessage() ]
-			);
-		}
+	private function getHtmlType(): string {
+		return $this->getConfig()['format'];
 	}
 }
diff --git a/includes/Rest/coreRoutes.json b/includes/Rest/coreRoutes.json
index f54a50a61c80..108bf99c1548 100644
--- a/includes/Rest/coreRoutes.json
+++ b/includes/Rest/coreRoutes.json
@@ -90,8 +90,7 @@
 			"RevisionLookup",
 			"TitleFormatter",
 			"TitleFactory",
-			"ParserCacheFactory",
-			"WikiPageFactory"
+			"VirtualRESTServiceClient"
 		],
 		"format": "bare"
 	},
@@ -104,8 +103,7 @@
 			"RevisionLookup",
 			"TitleFormatter",
 			"TitleFactory",
-			"ParserCacheFactory",
-			"WikiPageFactory"
+			"VirtualRESTServiceClient"
 		],
 		"format": "html"
 	},
@@ -118,8 +116,7 @@
 			"RevisionLookup",
 			"TitleFormatter",
 			"TitleFactory",
-			"ParserCacheFactory",
-			"WikiPageFactory"
+			"VirtualRESTServiceClient"
 		],
 		"format": "with_html"
 	},
diff --git a/includes/Rest/i18n/en.json b/includes/Rest/i18n/en.json
index c5f8e0e86248..ec986880217c 100644
--- a/includes/Rest/i18n/en.json
+++ b/includes/Rest/i18n/en.json
@@ -16,7 +16,6 @@
 	"rest-permission-denied-anon": "Not accessible by anonymous user",
 	"rest-permission-denied-title": "The user does not have rights to read title ($1)",
 	"rest-permission-denied-revision": "User doesn't have access to the requested revision ($1).",
-	"rest-resource-limit-exceeded": "Resources limits exceeded processing the request.",
 	"rest-pagehistory-incompatible-params": "Parameters \"older_than\" and \"newer_than\" cannot both be specified",
 	"rest-pagehistory-param-range-error": "Revision id must be greater than 0",
 	"rest-pagehistory-timestamp-error": "Unable to retrieve timestamp for the specified revision ($1)",
diff --git a/includes/Rest/i18n/qqq.json b/includes/Rest/i18n/qqq.json
index 32af0cf076eb..e97dee5277c5 100644
--- a/includes/Rest/i18n/qqq.json
+++ b/includes/Rest/i18n/qqq.json
@@ -17,7 +17,6 @@
 	"rest-permission-denied-anon": "Error message for REST API debugging, shown when the user is anonymous and therefore is denied permission to a resource",
 	"rest-permission-denied-title": "Error message for REST API debugging, shown if the user doesn't have read access to the specified title. Parameters:\n* $1 The page title",
 	"rest-permission-denied-revision": "Error message for REST API debugging, shown when the user doesn't have access to the specified revision. Parameters:\n* $1: the specified revision.",
-	"rest-resource-limit-exceeded": "Error message for REST API debugging, shown when the resource limit was exceeded by the request",
 	"rest-pagehistory-incompatible-params": "Error message for REST API debugging, shown if incompatible parameters are specified.",
 	"rest-pagehistory-param-range-error": "Error message for REST API debugging, shown if a revision id is provided but is out of range.",
 	"rest-pagehistory-timestamp-error": "Error message for REST API debugging, shown if an error occurred loading the timestamp for the specified revision.",
@@ -34,7 +33,7 @@
 	"rest-page-source-type-error": "Error message for REST API debugging, shown when trying to retrieve content for a page that has an unsupported content type",
 	"rest-no-revision": "Error message for REST API debugging, shown when fetching a revision by page ID fails. Parameters:\n* $1: The page ID we are getting revision from",
 	"rest-media-too-many-links": "Error message for REST API debugging, shown when there are too many media links on a page. Parameters:\n* $1: The page title.\n* $2: The number of links allowed.",
-	"rest-html-backend-error": "Error message for REST API debugging, shown when fetching Parsoid HTML from backend has failed. Parameters",
+	"rest-html-backend-error": "Error message for REST API debugging, shown when fetching Parsoid HTML from backend has failed.",
 	"rest-bad-json-body": "Error message for REST API debugging, shown when request body did not contain a JSON encoded object.",
 	"rest-json-body-parse-error": "Error message for REST API debugging, shown when parsing the JSON body failed. Parameters:\n* $1: the error message from the JSON parser.",
 	"rest-missing-body-field": "Error message for REST API debugging, shown when there is a mandatory field missing from the request body. Parameters:\n* $1: The field name",