Add HTTP upgrade functionality

Author: fredthomsen

hyper/common/connection.py

@@ -5,12 +5,11 @@
 
 Hyper's HTTP/1.1 and HTTP/2 abstraction layer.
 """
-from .exceptions import TLSUpgrade
+from .exceptions import TLSUpgrade, HTTPUpgrade
 from ..http11.connection import HTTP11Connection
-from ..http20.connection import HTTP20Connection
+from ..http20.connection import HTTP20Connection, H2C_PROTOCOL
 from ..tls import H2_NPN_PROTOCOLS
 
-
 class HTTPConnection(object):
     """
     An object representing a single HTTP connection to a server.
@@ -88,12 +87,15 @@ def request(self, method, url, body=None, headers={}):
             return self._conn.request(
                 method=method, url=url, body=body, headers=headers
             )
-        except TLSUpgrade as e:
-            # We upgraded in the NPN/ALPN handshake. We can just go straight to
-            # the world of HTTP/2. Replace the backing object and insert the
-            # socket into it.
-            assert e.negotiated in H2_NPN_PROTOCOLS
-
+        except (TLSUpgrade, HTTPUpgrade) as e:
+            # We upgraded in the NPN/ALPN handshake or via the HTTP Upgrade 
+            # mechanism. We can just go straight to the world of HTTP/2. 
+            #Replace the backing object and insert the socket into it.
+            if(type(e) is TLSUpgrade):
+                assert e.negotiated in H2_NPN_PROTOCOLS
+            else:
+                assert e.negotiated == H2C_PROTOCOL
+    
             self._conn = HTTP20Connection(
                 self._host, self._port, **self._h2_kwargs
             )

hyper/common/exceptions.py

@@ -51,3 +51,12 @@ def __init__(self, negotiated, sock):
         super(TLSUpgrade, self).__init__()
         self.negotiated = negotiated
         self.sock = sock
+
+class HTTPUpgrade(Exception):
+    """
+    We upgraded to a new protocol via the HTTP Upgrade response.
+    """
+    def __init__(self, negotiated, sock):
+        super(HTTPUpgrade, self).__init__()
+        self.negotiated = negotiated
+        self.sock = sock

hyper/http11/connection.py

@@ -8,15 +8,18 @@
 import logging
 import os
 import socket
+import base64
 
 from .response import HTTP11Response
 from ..tls import wrap_socket
 from ..common.bufsocket import BufferedSocket
-from ..common.exceptions import TLSUpgrade
+from ..common.exceptions import TLSUpgrade, HTTPUpgrade
 from ..common.headers import HTTPHeaderMap
 from ..common.util import to_bytestring
 from ..compat import bytes
 
+from ..http20.connection import H2C_PROTOCOL
+from ..packages.hyperframe.frame import SettingsFrame
 
 # We prefer pycohttpparser to the pure-Python interpretation
 try:  # pragma: no cover
@@ -94,7 +97,7 @@ def connect(self):
             if self.secure:
                 sock, proto = wrap_socket(sock, self.host, self.ssl_context)
 
-            log.debug("Selected NPN protocol: %s", proto)
+            log.debug("Selected protocol: %s", proto)
             sock = BufferedSocket(sock, self.network_buffer_size)
 
             if proto not in ('http/1.1', None):
@@ -130,6 +133,15 @@ def request(self, method, url, body=None, headers={}):
         if self._sock is None:
             self.connect()
 
+        #add HTTP Upgrade headers
+        headers[b'connection'] = b'Upgrade, HTTP2-Settings'
+        headers[b'upgrade'] = H2C_PROTOCOL
+        
+        #need to encode SETTINGS frame payload in Base64 and put into the HTTP-2 Settings header 
+        http2Settings = SettingsFrame(0)
+        http2Settings.settings[SettingsFrame.INITIAL_WINDOW_SIZE] = 65535
+        headers[b'HTTP2-Settings'] = base64.b64encode(http2Settings.serialize_body())
+
         # We may need extra headers.
         if body:
             body_type = self._add_body_headers(headers, body)
@@ -166,6 +178,11 @@ def get_response(self):
 
         self._sock.advance_buffer(response.consumed)
 
+        if(response.status == 101 and 
+           response.getheader('Connection') == 'Upgrade' and 
+           response.getheader('Upgrade') == H2C_PROTOCOL):
+            raise HTTPUpgrade(proto, sock)
+
         return HTTP11Response(
             response.status,
             response.msg.tobytes(),

hyper/http20/connection.py

@@ -25,9 +25,9 @@
 import logging
 import socket
 
-log = logging.getLogger(__name__)
+H2C_PROTOCOL = 'h2c'
 
-H2_CLEARTEXT_PROTOCOL = 'h2c'
+log = logging.getLogger(__name__)
 
 class HTTP20Connection(object):
     """
@@ -224,10 +224,10 @@ def connect(self):
             if self.secure:
                 sock, proto = wrap_socket(sock, self.host, self.ssl_context)
             else:
-                proto = H2_CLEARTEXT_PROTOCOL
+                proto = H2C_PROTOCOL
 
             log.debug("Selected NPN protocol: %s", proto)
-            assert proto in (H2_NPN_PROTOCOLS, H2_CLEARTEXT_PROTOCOL)
+            assert proto in (H2_NPN_PROTOCOLS, H2C_PROTOCOL)
 
             self._sock = BufferedSocket(sock, self.network_buffer_size)