Modify how stream resets are reported.

Fixes #147

Make the Stream when the stream is next accessed rather than immediately
the data is read.  This should avoid some errors that might occur when
there are multiple concurrent readers.

Author: Tim Emiola

hyper/http20/connection.py

@@ -19,7 +19,7 @@
 from .stream import Stream
 from .response import HTTP20Response, HTTP20Push
 from .window import FlowControlManager
-from .exceptions import ConnectionError
+from .exceptions import ConnectionError, StreamResetError
 from . import errors
 
 import errno
@@ -186,8 +186,12 @@ def request(self, method, url, body=None, headers=None):
         return stream_id
 
     def _get_stream(self, stream_id):
-        return (self.streams[stream_id] if stream_id is not None
-                else self.recent_stream)
+        if stream_id is None:
+            return self.recent_stream
+        elif stream_id in self.reset_streams or stream_id not in self.streams:
+            raise StreamResetError("Stream forcefully closed")
+        else:
+            return self.streams[stream_id]
 
     def get_response(self, stream_id=None):
         """

hyper/http20/stream.py

@@ -14,7 +14,6 @@
 the stream by the endpoint that initiated the stream.
 """
 from ..common.headers import HTTPHeaderMap
-from .exceptions import StreamResetError
 from .util import h2_safe_headers
 import logging
 
@@ -201,7 +200,7 @@ def receive_reset(self, event):
         Stream forcefully reset.
         """
         self.remote_closed = True
-        raise StreamResetError("Stream forcefully closed")
+        self._close_cb(self.stream_id)
 
     def get_headers(self):
         """

test/test_integration.py

@@ -678,7 +678,7 @@ def socket_handler(listener):
         conn._recv_cb()
 
         # However, attempting to get the response should.
-        with pytest.raises(KeyError):
+        with pytest.raises(StreamResetError):
             conn.get_response(stream_id)
 
         # Awesome, we're done now.
@@ -716,14 +716,14 @@ def socket_handler(listener):
         conn = self.get_connection()
         conn.request('GET', '/')
 
-        # Now, eat the RstStream frames. The first one throws a
-        # StreamResetError.
-        with pytest.raises(StreamResetError):
-            conn._single_read()
-
-        # The next should throw no exception.
+        # Now, eat the Rst frames. These should not cause an exception.
+        conn._single_read()
         conn._single_read()
 
+        # However, attempting to get the response should.
+        with pytest.raises(StreamResetError):
+            conn.get_response(1)
+
         assert conn.reset_streams == set([1])
 
         # Awesome, we're done now.