Rest: Turn Rest\EntryPoint into a MediaWikiEntryPoint subclass

The idea is for all entry points to use the MediaWikiEntryPoint
base class, to improve consistency and testability.

Bug: T354216
Change-Id: I3678afe32c7c1a313d2dcb1808286c25ecd167eb

4 files changed, 149 insertions, 116 deletions

diff --git a/includes/Rest/EntryPoint.php b/includes/Rest/EntryPoint.php
index aecae45e26ed..ec8dfa37c751 100644
--- a/includes/Rest/EntryPoint.php
+++ b/includes/Rest/EntryPoint.php
@@ -3,14 +3,14 @@
 namespace MediaWiki\Rest;
 
 use ExtensionRegistry;
-use MediaWiki;
 use MediaWiki\Config\Config;
 use MediaWiki\Config\ServiceOptions;
 use MediaWiki\Context\IContextSource;
 use MediaWiki\Context\RequestContext;
+use MediaWiki\EntryPointEnvironment;
 use MediaWiki\MainConfigNames;
+use MediaWiki\MediaWikiEntryPoint;
 use MediaWiki\MediaWikiServices;
-use MediaWiki\Request\WebResponse;
 use MediaWiki\Rest\BasicAccess\CompoundAuthorizer;
 use MediaWiki\Rest\BasicAccess\MWBasicAuthorizer;
 use MediaWiki\Rest\Reporter\MWErrorReporter;
@@ -19,21 +19,18 @@ use MediaWiki\Title\Title;
 use MWExceptionRenderer;
 use Wikimedia\Message\ITextFormatter;
 
-class EntryPoint {
-	/** @var RequestInterface */
-	private $request;
-	/** @var WebResponse */
-	private $webResponse;
-	/** @var Router */
-	private $router;
-	/** @var RequestContext */
-	private $context;
-	/** @var CorsUtils */
-	private $cors;
-	/** @var ?RequestInterface */
-	private static $mainRequest;
+/**
+ * @internal
+ */
+class EntryPoint extends MediaWikiEntryPoint {
+
+	private RequestInterface $request;
+	private ?Router $router = null;
+	private ?CorsUtils $cors  = null;
 
 	/**
+	 * @internal Public for use in core tests
+	 *
 	 * @param MediaWikiServices $services
 	 * @param IContextSource $context
 	 * @param RequestInterface $request
@@ -42,7 +39,7 @@ class EntryPoint {
 	 *
 	 * @return Router
 	 */
-	private static function createRouter(
+	public static function createRouter(
 		MediaWikiServices $services,
 		IContextSource $context,
 		RequestInterface $request,
@@ -84,64 +81,68 @@ class EntryPoint {
 	}
 
 	/**
+	 * @internal
 	 * @return RequestInterface The RequestInterface object used by this entry point.
 	 */
 	public static function getMainRequest(): RequestInterface {
-		if ( self::$mainRequest === null ) {
+		static $mainRequest = null;
+
+		if ( $mainRequest === null ) {
 			$conf = MediaWikiServices::getInstance()->getMainConfig();
-			self::$mainRequest = new RequestFromGlobals( [
+			$mainRequest = new RequestFromGlobals( [
 				'cookiePrefix' => $conf->get( MainConfigNames::CookiePrefix )
 			] );
 		}
-		return self::$mainRequest;
+
+		return $mainRequest;
 	}
 
-	public static function main() {
-		// URL safety checks
-		global $wgRequest;
+	protected function doSetup() {
+		parent::doSetup();
 
 		$context = RequestContext::getMain();
 
 		// Set $wgTitle and the title in RequestContext, as in api.php
 		global $wgTitle;
-		$wgTitle = Title::makeTitle( NS_SPECIAL, 'Badtitle/rest.php' );
+		$wgTitle = Title::makeTitle(
+			NS_SPECIAL,
+			'Badtitle/rest.php'
+		);
 		$context->setTitle( $wgTitle );
 
-		$services = MediaWikiServices::getInstance();
-		$conf = $services->getMainConfig();
-
-		$responseFactory = new ResponseFactory( self::getTextFormatters( $services ) );
-		$responseFactory->setShowExceptionDetails( MWExceptionRenderer::shouldShowExceptionDetails() );
+		$responseFactory = new ResponseFactory( $this->getTextFormatters() );
+		$responseFactory->setShowExceptionDetails(
+			MWExceptionRenderer::shouldShowExceptionDetails()
+		);
 
-		$cors = new CorsUtils(
+		$this->cors = new CorsUtils(
 			new ServiceOptions(
-				CorsUtils::CONSTRUCTOR_OPTIONS, $conf
+				CorsUtils::CONSTRUCTOR_OPTIONS,
+				$this->getServiceContainer()->getMainConfig()
 			),
 			$responseFactory,
 			$context->getUser()
 		);
 
-		$request = self::getMainRequest();
-
-		$router = self::createRouter( $services, $context, $request, $responseFactory, $cors );
-
-		$entryPoint = new self(
-			$context,
-			$request,
-			$wgRequest->response(),
-			$router,
-			$cors
-		);
-		$entryPoint->execute();
+		if ( !$this->router ) {
+			$this->router = $this->createRouter(
+				$this->getServiceContainer(),
+				$context,
+				$this->request,
+				$responseFactory,
+				$this->cors
+			);
+		}
 	}
 
 	/**
 	 * Get a TextFormatter array from MediaWikiServices
 	 *
-	 * @param MediaWikiServices $services
 	 * @return ITextFormatter[]
 	 */
-	private static function getTextFormatters( MediaWikiServices $services ) {
+	private function getTextFormatters() {
+		$services = $this->getServiceContainer();
+
 		$code = $services->getContentLanguage()->getCode();
 		$langs = array_unique( [ $code, 'en' ] );
 		$textFormatters = [];
@@ -150,11 +151,13 @@ class EntryPoint {
 		foreach ( $langs as $lang ) {
 			$textFormatters[] = $factory->getTextFormatter( $lang );
 		}
+
 		return $textFormatters;
 	}
 
 	/**
 	 * @param Config $conf
+	 *
 	 * @return string[]
 	 */
 	private static function getRouteFiles( $conf ) {
@@ -166,59 +169,80 @@ class EntryPoint {
 			$conf->get( MainConfigNames::RestAPIAdditionalRouteFiles )
 		);
 		foreach ( $routeFiles as &$file ) {
-			if ( str_starts_with( $file, '/' ) ) {
+			if (
+				str_starts_with( $file, '/' )
+			) {
 				// Allow absolute paths on non-Windows
-			} elseif ( str_starts_with( $file, 'extensions/' ) ) {
+			} elseif (
+				str_starts_with( $file, 'extensions/' )
+			) {
 				// Support hacks like Wikibase.ci.php
-				$file = substr_replace( $file, $extensionsDir, 0, strlen( 'extensions' ) );
+				$file = substr_replace( $file, $extensionsDir,
+					0, strlen( 'extensions' ) );
 			} else {
 				$file = "$IP/$file";
 			}
 		}
+
 		return $routeFiles;
 	}
 
-	public function __construct( RequestContext $context, RequestInterface $request,
-		WebResponse $webResponse, Router $router, CorsUtils $cors
+	public function __construct(
+		RequestInterface $request,
+		RequestContext $context,
+		EntryPointEnvironment $environment,
+		MediaWikiServices $mediaWikiServices
 	) {
-		$this->context = $context;
+		parent::__construct( $context, $environment, $mediaWikiServices );
+
 		$this->request = $request;
-		$this->webResponse = $webResponse;
+	}
+
+	/**
+	 * Sets the router to use.
+	 * Intended for testing.
+	 *
+	 * @param Router $router
+	 */
+	public function setRouter( Router $router ): void {
 		$this->router = $router;
-		$this->cors = $cors;
 	}
 
 	public function execute() {
-		ob_start();
+		$this->startOutputBuffer();
+
 		$response = $this->cors->modifyResponse(
 			$this->request,
 			$this->router->execute( $this->request )
 		);
 
-		$this->webResponse->header(
-			'HTTP/' . $response->getProtocolVersion() . ' ' .
-			$response->getStatusCode() . ' ' .
-			$response->getReasonPhrase() );
+		$webResponse = $this->getResponse();
+
+		$webResponse->header(
+			'HTTP/' . $response->getProtocolVersion() . ' ' . $response->getStatusCode() . ' ' .
+			$response->getReasonPhrase()
+		);
 
 		foreach ( $response->getRawHeaderLines() as $line ) {
-			$this->webResponse->header( $line );
+			$webResponse->header( $line );
 		}
 
 		foreach ( $response->getCookies() as $cookie ) {
-			$this->webResponse->setCookie(
+			$webResponse->setCookie(
 				$cookie['name'],
 				$cookie['value'],
 				$cookie['expiry'],
-				$cookie['options'] );
+				$cookie['options']
+			);
 		}
 
 		// Clear all errors that might have been displayed if display_errors=On
-		ob_end_clean();
+		$this->discardOutputBuffer();
 
 		$stream = $response->getBody();
 		$stream->rewind();
 
-		MediaWiki::preOutputCommit( $this->context );
+		$this->prepareForOutput();
 
 		if ( $stream instanceof CopyableStreamInterface ) {
 			$stream->copyToStream( fopen( 'php://output', 'w' ) );
@@ -228,11 +252,9 @@ class EntryPoint {
 				if ( $buffer === '' ) {
 					break;
 				}
-				echo $buffer;
+				$this->print( $buffer );
 			}
 		}
-
-		$mw = new MediaWiki;
-		$mw->doPostOutputShutdown();
 	}
+
 }
diff --git a/rest.php b/rest.php
index f647f91fe0e4..62f298712f33 100644
--- a/rest.php
+++ b/rest.php
@@ -21,6 +21,8 @@
  * @file
  */
 
+use MediaWiki\EntryPointEnvironment;
+use MediaWiki\MediaWikiServices;
 use MediaWiki\Rest\EntryPoint;
 
 define( 'MW_REST_API', true );
@@ -28,4 +30,9 @@ define( 'MW_ENTRY_POINT', 'rest' );
 
 require __DIR__ . '/includes/WebStart.php';
 
-EntryPoint::main();
+( new EntryPoint(
+	EntryPoint::getMainRequest(),
+	RequestContext::getMain(),
+	new EntryPointEnvironment(),
+	MediaWikiServices::getInstance()
+) )->run();
diff --git a/tests/phpunit/includes/Rest/EntryPointTest.php b/tests/phpunit/includes/Rest/EntryPointTest.php
index 775987fe9d3d..4275a59dcbad 100644
--- a/tests/phpunit/includes/Rest/EntryPointTest.php
+++ b/tests/phpunit/includes/Rest/EntryPointTest.php
@@ -4,13 +4,12 @@ namespace MediaWiki\Tests\Rest;
 
 use GuzzleHttp\Psr7\Stream;
 use GuzzleHttp\Psr7\Uri;
-use MediaWiki\Context\RequestContext;
-use MediaWiki\Request\WebResponse;
-use MediaWiki\Rest\CorsUtils;
+use MediaWiki\MainConfigNames;
 use MediaWiki\Rest\EntryPoint;
 use MediaWiki\Rest\Handler;
 use MediaWiki\Rest\RequestData;
 use MediaWiki\Rest\RequestInterface;
+use MediaWiki\Tests\MockEnvironment;
 use MediaWikiIntegrationTestCase;
 
 /**
@@ -20,24 +19,34 @@ use MediaWikiIntegrationTestCase;
 class EntryPointTest extends MediaWikiIntegrationTestCase {
 	use RestTestTrait;
 
+	public function setUp(): void {
+		parent::setUp();
+
+		$this->overrideConfigValue( MainConfigNames::RestPath, '/rest' );
+	}
+
 	private function createRouter( RequestInterface $request ) {
 		return $this->newRouter( [
 			'request' => $request
 		] );
 	}
 
-	private function createWebResponse() {
-		return $this->getMockBuilder( WebResponse::class )
-			->onlyMethods( [ 'header' ] )
-			->getMock();
-	}
-
-	private function createCorsUtils() {
-		$cors = $this->createMock( CorsUtils::class );
-		$cors->method( 'modifyResponse' )
-			->willReturnArgument( 1 );
+	/**
+	 * @param RequestData $request
+	 * @param MockEnvironment $env
+	 *
+	 * @return EntryPoint
+	 */
+	private function getEntryPoint( RequestData $request, MockEnvironment $env ): EntryPoint {
+		$entryPoint = new EntryPoint(
+			$request,
+			$env->makeFauxContext(),
+			$env,
+			$this->getServiceContainer()
+		);
 
-		return $cors;
+		$entryPoint->setRouter( $this->createRouter( $request ) );
+		return $entryPoint;
 	}
 
 	public static function mockHandlerHeader() {
@@ -51,31 +60,21 @@ class EntryPointTest extends MediaWikiIntegrationTestCase {
 	}
 
 	public function testHeader() {
-		$webResponse = $this->createWebResponse();
-		$expectedHeaders = [
-			'HTTP/1.1 200 OK',
-			'Foo: Bar',
-		];
-		$webResponse->expects( $this->atLeast( count( $expectedHeaders ) ) )
-			->method( 'header' )
-			->willReturnCallback( static function ( $headerString ) use ( &$expectedHeaders ) {
-				$headerIdx = array_search( $headerString, $expectedHeaders, true );
-				if ( $headerIdx !== false ) {
-					unset( $expectedHeaders[$headerIdx] );
-				}
-			} );
-
-		$request = new RequestData( [ 'uri' => new Uri( '/rest/mock/EntryPoint/header' ) ] );
+		$uri = '/rest/mock/EntryPoint/header';
+		$request = new RequestData( [ 'uri' => new Uri( $uri ) ] );
 
-		$entryPoint = new EntryPoint(
-			RequestContext::getMain(),
+		$env = new MockEnvironment();
+		$env->setRequestInfo( $uri );
+
+		$entryPoint = $this->getEntryPoint(
 			$request,
-			$webResponse,
-			$this->createRouter( $request ),
-			$this->createCorsUtils()
+			$env
 		);
-		$entryPoint->execute();
-		$this->assertCount( 0, $expectedHeaders );
+
+		$entryPoint->enableOutputCapture();
+		$entryPoint->run();
+		$env->assertHeaderValue( 'Bar', 'Foo' );
+		$env->assertStatusCode( 200 );
 	}
 
 	public static function mockHandlerBodyRewind() {
@@ -94,17 +93,22 @@ class EntryPointTest extends MediaWikiIntegrationTestCase {
 	 * Make sure EntryPoint rewinds a seekable body stream before reading.
 	 */
 	public function testBodyRewind() {
-		$request = new RequestData( [ 'uri' => new Uri( '/rest/mock/EntryPoint/bodyRewind' ) ] );
-		$entryPoint = new EntryPoint(
-			RequestContext::getMain(),
+		$uri = '/rest/mock/EntryPoint/bodyRewind';
+		$request = new RequestData( [ 'uri' => new Uri( $uri ) ] );
+
+		$env = new MockEnvironment();
+		$env->setRequestInfo( $uri );
+
+		$entryPoint = $this->getEntryPoint(
 			$request,
-			$this->createWebResponse(),
-			$this->createRouter( $request ),
-			$this->createCorsUtils()
+			$env
 		);
-		ob_start();
-		$entryPoint->execute();
-		$this->assertSame( 'hello', ob_get_clean() );
+
+		$entryPoint->enableOutputCapture();
+		$entryPoint->run();
+
+		// NOTE: MediaWikiEntryPoint::doPostOutputShutdown flushes all output buffers
+		$this->assertStringContainsString( 'hello', $entryPoint->getCapturedOutput() );
 	}
 
 }
diff --git a/tests/phpunit/structure/RestStructureTest.php b/tests/phpunit/structure/RestStructureTest.php
index ebaa5ba90420..b28ad8fe31a4 100644
--- a/tests/phpunit/structure/RestStructureTest.php
+++ b/tests/phpunit/structure/RestStructureTest.php
@@ -108,8 +108,7 @@ class RestStructureTest extends MediaWikiIntegrationTestCase {
 			$services = $this->getFakeServiceContainer();
 
 			// NOTE: createRouter() implements the logic for determining the list of route files to load.
-			$entryPoint = TestingAccessWrapper::newFromClass( EntryPoint::class );
-			$router = $entryPoint->createRouter( $services, $context, new RequestData(), $responseFactory, $cors );
+			$router = EntryPoint::createRouter( $services, $context, new RequestData(), $responseFactory, $cors );
 			$router = TestingAccessWrapper::newFromObject( $router );
 		}
 
@@ -132,8 +131,9 @@ class RestStructureTest extends MediaWikiIntegrationTestCase {
 			$responseFactory = $this->createNoOpMock( ResponseFactory::class );
 			$cors = $this->createNoOpMock( CorsUtils::class );
 
-			$this->router = TestingAccessWrapper::newFromClass( EntryPoint::class )
-				->createRouter( $this->getServiceContainer(), $context, new RequestData(), $responseFactory, $cors );
+			$this->router = EntryPoint::createRouter(
+				$this->getServiceContainer(), $context, new RequestData(), $responseFactory, $cors
+			);
 		}
 		return $this->router;
 	}