Handle compressed response body

lib/Http/Response.php

@@ -96,7 +96,7 @@ public function __construct(
         $version = '1.1',
         $message = null
     ) {
-        $this->status = intval($status);
+        $this->status = (int) $status;
         $this->body = $body;
         $this->version = $version;
         $this->message = $message;
@@ -165,19 +165,21 @@ public function getMessage()
      */
     public function getBody()
     {
-        // Decode the body if it was transfer-encoded
-        switch (strtolower($this->getHeader('transfer-encoding'))) {
-            // Handle chunked body
-            case 'chunked':
-                return self::decodeChunkedBody($this->body);
-                break;
-
-            // No transfer encoding, or unknown encoding extension:
-            // return body as is
-            default:
-                return $this->body;
-                break;
+        $body = $this->body;
+
+        if ('chunked' === strtolower($this->getHeader('transfer-encoding'))) {
+            $body = self::decodeChunkedBody($body);
         }
+
+        $contentEncoding = strtolower($this->getHeader('content-encoding'));
+
+        if ('gzip' === $contentEncoding) {
+            $body = self::decodeGzip($body);
+        } elseif ('deflate' === $contentEncoding) {
+            $body = self::decodeDeflate($body);
+        }
+
+        return $body;
     }
 
     /**
@@ -225,9 +227,9 @@ public function getHeader($header)
         $header = ucwords(strtolower($header));
         if (array_key_exists($header, $this->headers)) {
             return $this->headers[$header];
-        } else {
-            return null;
         }
+
+        return null;
     }
 
     /**
@@ -272,7 +274,7 @@ public static function fromString($responseStr)
     {
         // First, split body and headers
         $matches = preg_split('|(?:\r?\n){2}|m', $responseStr, 2);
-        if ($matches and sizeof($matches) == 2) {
+        if ($matches and 2 === count($matches)) {
             list ($headerLines, $body) = $matches;
         } else {
             throw new Exception(
@@ -321,28 +323,89 @@ public static function fromString($responseStr)
      * @param string $body
      *
      * @throws \EasyRdf\Exception
+     *
      * @return string
      */
     public static function decodeChunkedBody($body)
     {
         $decBody = '';
 
         while (trim($body)) {
-            if (preg_match('/^([\da-fA-F]+)[^\r\n]*\r\n/sm', $body, $m)) {
-                $length = hexdec(trim($m[1]));
-                $cut = strlen($m[0]);
-                $decBody .= substr($body, $cut, $length);
-                $body = substr($body, $cut + $length + 2);
-            } else {
+            if (!preg_match("/^([\da-fA-F]+)[^\r\n]*\r\n/sm", $body, $m)) {
                 throw new Exception(
-                    "Failed to decode chunked body in HTTP response."
+                    "Error parsing body - doesn't seem to be a chunked message"
                 );
             }
+            $length   = hexdec(trim($m[1]));
+            $cut      = strlen($m[0]);
+            $decBody .= substr($body, $cut, $length);
+            $body     = substr($body, $cut + $length + 2);
         }
 
         return $decBody;
     }
 
+    /**
+     * Decode a gzip encoded message (when Content-encoding = gzip)
+     *
+     * Currently requires PHP with zlib support
+     *
+     * @param string $body
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    public static function decodeGzip($body)
+    {
+        if (!function_exists('gzinflate')) {
+            throw new Exception(
+                'zlib extension is required in order to decode "gzip" encoding'
+            );
+        }
+
+        return gzinflate(substr($body, 10));
+    }
+
+    /**
+     * Decode a zlib deflated message (when Content-encoding = deflate)
+     *
+     * Currently requires PHP with zlib support
+     *
+     * @param string $body
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    public static function decodeDeflate($body)
+    {
+        if (!function_exists('gzuncompress')) {
+            throw new Exception(
+                'zlib extension is required in order to decode "deflate" encoding'
+            );
+        }
+
+        /**
+         * Some servers (IIS ?) send a broken deflate response, without the
+         * RFC-required zlib header.
+         *
+         * We try to detect the zlib header, and if it does not exist we
+         * teat the body is plain DEFLATE content.
+         *
+         * This method was adapted from PEAR HTTP_Request2 by (c) Alexey Borzov
+         *
+         * @link http://framework.zend.com/issues/browse/ZF-6040
+         */
+        $zlibHeader = unpack('n', substr($body, 0, 2));
+
+        if ($zlibHeader[1] % 31 === 0) {
+            return gzuncompress($body);
+        }
+
+        return gzinflate($body);
+    }
+
 
     /**
      * Get the entire response as string

test/EasyRdf/Http/ResponseTest.php

@@ -100,6 +100,44 @@ public function testInvalidStatusLine()
         );
     }
 
+    public function testGzipResponse()
+    {
+        $res = Response::fromString(readFixture('response_gzip'));
+
+        $this->assertEquals('gzip', strtolower($res->getHeader('content-encoding')));
+        $this->assertEquals('0b13cb193de9450aa70a6403e2c9902f', md5($res->getBody()));
+        $this->assertEquals('f24dd075ba2ebfb3bf21270e3fdc5303', md5($res->getRawBody()));
+    }
+
+    public function testDeflateResponse()
+    {
+        $res = Response::fromString(readFixture('response_deflate'));
+
+        $this->assertEquals('deflate', strtolower($res->getHeader('content-encoding')));
+        $this->assertEquals('0b13cb193de9450aa70a6403e2c9902f', md5($res->getBody()));
+        $this->assertEquals('ad62c21c3aa77b6a6f39600f6dd553b8', md5($res->getRawBody()));
+    }
+
+    /**
+     * Make sure wer can handle non-RFC complient "deflate" responses.
+     *
+     * Unlike stanrdard 'deflate' response, those do not contain the zlib header
+     * and trailer. Unfortunately some buggy servers (read: IIS) send those and
+     * we need to support them.
+     *
+     * @link http://framework.zend.com/issues/browse/ZF-6040
+     */
+    public function testNonStandardDeflateResponseZF6040()
+    {
+        $this->markTestSkipped('Not correctly handling non-RFC complient "deflate" responses');
+
+        $res = Response::fromString(readFixture('response_deflate_iis'));
+
+        $this->assertEquals('deflate', strtolower($res->getHeader('content-encoding')));
+        $this->assertEquals('d82c87e3d5888db0193a3fb12396e616', md5($res->getBody()));
+        $this->assertEquals('c830dd74bb502443cf12514c185ff174', md5($res->getRawBody()));
+    }
+
     public function testGetBodyChunked()
     {
         $response = Response::fromString(
@@ -115,7 +153,7 @@ public function testInvalidChunkedBody()
     {
         $this->setExpectedException(
             'EasyRdf\Exception',
-            'Failed to decode chunked body in HTTP response.'
+            'Error parsing body - doesn\'t seem to be a chunked message'
         );
         $response = Response::fromString(
             "HTTP/1.1 200 OK\r\nTransfer-Encoding: chunked\r\n\r\nINVALID"