Fix for 'Failed to parse headers' warning

src/urllib3/exceptions.py

@@ -236,8 +236,8 @@ def __init__(self, scheme):
 
 class HeaderParsingError(HTTPError):
     "Raised by assert_header_parsing, but we convert it to a log.warning statement."
-    def __init__(self, defects, unparsed_data):
-        message = '%s, unparsed data: %r' % (defects or 'Unknown', unparsed_data)
+    def __init__(self, defects):
+        message = '%s' % (defects or 'Unknown')
         super(HeaderParsingError, self).__init__(message)
 
 

src/urllib3/util/response.py

@@ -37,7 +37,6 @@ def is_fp_closed(obj):
 
 def assert_header_parsing(headers):
     """
-    Asserts whether all headers have been successfully parsed.
     Extracts encountered errors from the result of parsing headers.
 
     Only works on Python 3.
@@ -56,14 +55,9 @@ def assert_header_parsing(headers):
             type(headers)))
 
     defects = getattr(headers, 'defects', None)
-    get_payload = getattr(headers, 'get_payload', None)
 
-    unparsed_data = None
-    if get_payload:  # Platform-specific: Python 3.
-        unparsed_data = get_payload()
-
-    if defects or unparsed_data:
-        raise HeaderParsingError(defects=defects, unparsed_data=unparsed_data)
+    if defects:
+        raise HeaderParsingError(defects=defects)
 
 
 def is_response_to_head(response):

test/test_exceptions.py

@@ -32,7 +32,6 @@ def test_exceptions(self, exception):
 
 class TestFormat(object):
     def test_header_parsing_errors(self):
-        hpe = HeaderParsingError('defects', 'unparsed_data')
+        hpe = HeaderParsingError('defects')
 
         assert 'defects' in str(hpe)
-        assert 'unparsed_data' in str(hpe)

test/with_dummyserver/test_socketlevel.py

@@ -1328,6 +1328,35 @@ def test_header_without_colon_or_value(self):
         ])
 
 
+@pytest.mark.skipif(
+    issubclass(httplib.HTTPMessage, MimeToolMessage),
+    reason='Header parsing errors not available'
+)
+class TestOkayHeaders(SocketDummyServerTestCase):
+
+    def _test_okay_header_parsing(self, header):
+        self.start_response_handler((
+           b'HTTP/1.1 200 OK\r\n'
+           b'Content-Length: 0\r\n'
+           ) + header + b'\r\n\r\n'
+        )
+
+        pool = HTTPConnectionPool(self.host, self.port, retries=False)
+        self.addCleanup(pool.close)
+
+        with LogRecorder() as logs:
+            pool.request('GET', '/')
+
+        for record in logs:
+            assert 'Failed to parse headers' not in record.msg
+
+    def test_header_text_plain(self):
+        self._test_okay_header_parsing(b'Content-type: text/plain')
+
+    def test_header_message_rfc822(self):
+        self._test_okay_header_parsing(b'Content-type: message/rfc822')
+
+
 class TestHEAD(SocketDummyServerTestCase):
     def test_chunked_head_response_does_not_hang(self):
         self.start_response_handler(