+MessageUtil::setContentTypeHeader()

Author: codemasher

src/MessageUtil.php

@@ -13,7 +13,7 @@
 use Psr\Http\Message\{MessageInterface, RequestInterface, ResponseInterface};
 use RuntimeException, Throwable;
 use function call_user_func, extension_loaded, function_exists, gzdecode, gzinflate, gzuncompress, implode,
-	in_array, json_decode, json_encode, simplexml_load_string, sprintf, strtolower;
+	in_array, json_decode, json_encode, simplexml_load_string, sprintf, strtolower, trim;
 use const JSON_THROW_ON_ERROR;
 
 /**
@@ -146,4 +146,28 @@ public static function setContentLengthHeader(MessageInterface $message):Message
 		return $message;
 	}
 
+	/**
+	 * Tries to determine the content type from the given values and sets the Content-Type header accordingly,
+	 * throws if no mime type could be guessed.
+	 *
+	 * @throws \RuntimeException
+	 */
+	public static function setContentTypeHeader(
+		MessageInterface $message,
+		string           $filename = null,
+		string           $extension = null
+	):MessageInterface{
+		$mime = (
+			   MimeTypeUtil::getFromExtension(trim(($extension ?? ''), ".\t\n\r\0\x0B"))
+			?? MimeTypeUtil::getFromFilename(($filename ?? ''))
+			?? MimeTypeUtil::getFromContent(self::getContents($message))
+		);
+
+		if($mime === null){
+			throw new RuntimeException('could not determine content type');
+		}
+
+		return $message->withHeader('Content-Type', $mime);
+	}
+
 }

tests/MessageUtilTest.php

@@ -15,6 +15,7 @@
 use PHPUnit\Framework\TestCase;
 use RuntimeException;
 use function extension_loaded;
+use function file_get_contents;
 use function function_exists;
 use function sprintf;
 use function str_repeat;
@@ -162,4 +163,29 @@ public function testSetContentLengthHeader():void{
 		);
 	}
 
+	public static function contentTypeProvider():array{
+		return [
+			'text/plain'             => ['foo', null, null, 'text/plain'],
+			'application/json'       => ['{}', null, null, 'application/json'],
+			'text/javascript (name)' => ['{}', 'test.js', null, 'text/javascript'],
+			'text/javascript (ext)'  => ['{}', null, 'js', 'text/javascript'],
+			'text/x-php'             => [file_get_contents(__FILE__), null, null, 'text/x-php'],
+			'text/markdown'          => [file_get_contents(__DIR__.'/../README.md'), null, 'md', 'text/markdown'],
+		];
+	}
+
+	#[DataProvider('contentTypeProvider')]
+	public function testSetContentTypeHeader(string $content, ?string $filename, ?string $extension, string $expectedMIME):void{
+
+		$message = $this->requestFactory
+			->createRequest('GET', 'https://example.com')
+			->withBody($this->streamFactory->createStream($content))
+		;
+
+		$message = MessageUtil::setContentTypeHeader($message, $filename, $extension);
+
+		$this::assertTrue($message->hasHeader('content-type'));
+		$this::assertSame($expectedMIME, $message->getHeaderLine('content-type'));
+	}
+
 }

tests/MimeTypeUtilTest.php

@@ -25,6 +25,7 @@ public function testGetMimetypeFromExtension():void{
 	}
 
 	public function testGetMimeTypeFromFileName():void{
+		$this::assertNull(MimeTypeUtil::getFromFilename(''));
 		$this::assertSame('application/json', MimeTypeUtil::getFromFilename('/path/to/some/file.json'));
 	}