Support for deflate raw (Closes #34)

index.js

@@ -13,10 +13,36 @@ export default function decompressResponse(response) {
 
 	let isEmpty = true;
 
+	function handleContentEncoding(data) {
+		const decompressStream = contentEncoding === 'br'
+			? zlib.createBrotliDecompress()
+			: ((contentEncoding === 'deflate' && data.length > 0 && (data[0] & 0x08) === 0) // eslint-disable-line no-bitwise
+				? zlib.createInflateRaw()
+				: zlib.createUnzip());
+
+		decompressStream.once('error', error => {
+			if (isEmpty && !response.readable) {
+				finalStream.end();
+				return;
+			}
+
+			finalStream.destroy(error);
+		});
+
+		checker.pipe(decompressStream).pipe(finalStream);
+	}
+
 	const checker = new TransformStream({
 		transform(data, _encoding, callback) {
+			if (isEmpty === false) {
+				callback(null, data);
+				return;
+			}
+
 			isEmpty = false;
 
+			handleContentEncoding(data);
+
 			callback(null, data);
 		},
 
@@ -34,19 +60,8 @@ export default function decompressResponse(response) {
 		},
 	});
 
-	const decompressStream = contentEncoding === 'br' ? zlib.createBrotliDecompress() : zlib.createUnzip();
-
-	decompressStream.once('error', error => {
-		if (isEmpty && !response.readable) {
-			finalStream.end();
-			return;
-		}
-
-		finalStream.destroy(error);
-	});
-
 	mimicResponse(response, finalStream);
-	response.pipe(checker).pipe(decompressStream).pipe(finalStream);
+	response.pipe(checker);
 
 	return finalStream;
 }

test/test.js

@@ -29,6 +29,13 @@ test.before('setup', async () => {
 		response.end(await zlibP.deflate(fixture));
 	});
 
+	server.on('/deflateRaw', async (request, response) => {
+		response.statusCode = 200;
+		response.setHeader('content-encoding-type', 'text/plain');
+		response.setHeader('content-encoding', 'deflate');
+		response.end(await zlibP.deflateRaw(fixture));
+	});
+
 	server.on('/brotli', async (request, response) => {
 		response.statusCode = 200;
 		response.setHeader('content-type', 'text/plain');
@@ -91,6 +98,17 @@ test('decompress deflated content', async t => {
 	t.is(await getStream(response), fixture);
 });
 
+test('decompress raw-deflated content', async t => {
+	const response = decompressResponse(await httpGetP(`${server.url}/deflateRaw`));
+
+	t.is(typeof response.httpVersion, 'string');
+	t.truthy(response.headers);
+
+	response.setEncoding('utf8');
+
+	t.is(await getStream(response), fixture);
+});
+
 test('decompress brotli content', async t => {
 	const response = decompressResponse(await httpGetP(`${server.url}/brotli`));