RequestInterface: add hasBody()

hasBody() provides an easy way to check whether the request contains
payload data. This ensures this check is performed consistently and in
accordance with RFC 9110.

Change-Id: If15f2cb6239c4c8170e70a5bec8a5f0821361275

includes/Rest/RequestBase.php

@@ -128,4 +128,34 @@ abstract class RequestBase implements RequestInterface {
 		}
 		return $ct;
 	}
+
+	/**
+	 * Return true if the client provided a content-length header or a
+	 * transfer-encoding header.
+	 *
+	 * @see https://www.rfc-editor.org/rfc/rfc9110.html#name-content-length
+	 *
+	 * @return bool
+	 */
+	public function hasBody(): bool {
+		// From RFC9110, section 8.6: A user agent SHOULD send Content-Length
+		// in a request when the method defines a meaning for enclosed content
+		// and it is not sending Transfer-Encoding. [...]
+		// A user agent SHOULD NOT send a Content-Length header field when the
+		// request message does not contain content and the method semantics do
+		// not anticipate such data.
+
+		if ( $this->getHeaderLine( 'content-length' ) !== '' ) {
+			// If a content length is set, there is a body
+			return true;
+		}
+
+		if ( $this->getHeaderLine( 'transfer-encoding' ) !== '' ) {
+			// If a transfer encoding is set, there is a body
+			return true;
+		}
+
+		return false;
+	}
+
 }

includes/Rest/RequestData.php

@@ -102,4 +102,21 @@ class RequestData extends RequestBase {
 	public function getPostParams() {
 		return $this->postParams;
 	}
+
+	public function hasBody(): bool {
+		if ( parent::hasBody() ) {
+			return true;
+		}
+
+		if ( $this->parsedBody !== null ) {
+			return true;
+		}
+
+		if ( $this->getBody()->getContents() !== '' ) {
+			return true;
+		}
+
+		return false;
+	}
+
 }

includes/Rest/RequestInterface.php

@@ -268,4 +268,12 @@ interface RequestInterface {
 	public function setParsedBody( ?array $data );
 
 	public function getBodyType(): ?string;
+
+	/**
+	 * Determines whether the request has body data associated with it.
+	 * Note that this method may return true even if the body is empty.
+	 *
+	 * @return bool
+	 */
+	public function hasBody(): bool;
 }

tests/phpunit/unit/includes/Rest/RequestBaseTest.php

@@ -64,4 +64,34 @@ class RequestBaseTest extends \MediaWikiUnitTestCase {
 		$rb->setHeaders( [ 'Content-type' => 'application/json' ] );
 		$this->assertSame( [ 'application/json' ], $rb->getHeaders()[ 'Content-type' ] );
 	}
+
+	public static function provideHasBody() {
+		yield 'nothing'
+		=> [ [], false ];
+
+		yield 'content-length: 1'
+		=> [ [ 'content-length' => '1' ], true ];
+
+		yield 'content-length: 0'
+		=> [ [ 'content-length' => '0' ], true ];
+
+		yield 'content-length empty'
+		=> [ [ 'content-length' => '' ], false ];
+
+		yield 'transfer-encoding: chunked'
+		=> [ [ 'transfer-encoding' => 'chunked' ], true ];
+
+		yield 'transfer-encoding empty'
+		=> [ [ 'transfer-encoding' => '' ], false ];
+	}
+
+	/**
+	 * @dataProvider provideHasBody
+	 */
+	public function testHasBody( $headers, $expected ) {
+		$rb = $this->getMockForAbstractClass( RequestBase::class, [ 'cookiePrefix' ] );
+		$rb->setHeaders( $headers );
+		$this->assertSame( $expected, $rb->hasBody() );
+	}
+
 }

tests/phpunit/unit/includes/Rest/RequestDataTest.php

@@ -221,4 +221,47 @@ class RequestDataTest extends \MediaWikiUnitTestCase {
 		$this->assertSame( $expectedResult, $request->getBodyType() );
 	}
 
+	public static function provideHasBody() {
+		yield 'nothing'
+		=> [ [], false ];
+
+		yield 'content-length: 1'
+		=> [ [ 'content-length' => '1' ], true ];
+
+		yield 'content-length: 0'
+		=> [ [ 'content-length' => '0' ], true ];
+
+		yield 'content-length empty'
+		=> [ [ 'content-length' => '' ], false ];
+
+		yield 'transfer-encoding: chunked'
+		=> [ [ 'transfer-encoding' => 'chunked' ], true ];
+
+		yield 'transfer-encoding empty'
+		=> [ [ 'transfer-encoding' => '' ], false ];
+	}
+
+	/**
+	 * @dataProvider provideHasBody
+	 */
+	public function testHasBodyBasedOnHeader( $headers, $expected ) {
+		$request = new RequestData( [
+			'headers' => $headers
+		] );
+		$this->assertSame( $expected, $request->hasBody() );
+	}
+
+	public function testHasBodyWithContent() {
+		$request = new RequestData( [
+			'bodyContents' => 'test test test'
+		] );
+		$this->assertTrue( $request->hasBody() );
+	}
+
+	public function testHasBodyWithParsedBody() {
+		$request = new RequestData( [
+			'parsedBody' => [ 'foo' => 'bar' ]
+		] );
+		$this->assertTrue( $request->hasBody() );
+	}
 }