feat(http2): IH2EventsHandler, http2 module

scrapy/core/http2/protocol.py

@@ -0,0 +1,136 @@
+from h2.connection import H2Connection
+from h2.config import H2Configuration
+from h2.events import (
+    ConnectionTerminated, DataReceived, ResponseReceived, StreamEnded,
+    StreamReset, TrailersReceived, WindowUpdated
+)
+
+from scrapy.http import Request
+
+from twisted.internet.defer import maybeDeferred
+from twisted.internet.protocol import Protocol
+
+from urllib.parse import urlparse
+
+from zope.interface import implementer, Interface
+
+
+class IH2EventsHandler(Interface):
+    def connection_terminated(event: ConnectionTerminated):
+        pass
+
+    def data_received(event: DataReceived):
+        pass
+
+    def response_received(event: ResponseReceived):
+        pass
+
+    def stream_ended(event: StreamEnded):
+        pass
+
+    def stream_reset(event: StreamReset):
+        pass
+
+    def trailers_received(event: TrailersReceived):
+        pass
+
+    def window_updated(event: WindowUpdated):
+        pass
+
+
+@implementer(IH2EventsHandler)
+class H2ClientProtocol(Protocol):
+    def __init__(self):
+        config = H2Configuration(client_side=True)
+        self.conn = H2Connection(config=config)
+        
+        # List of ongoing stream id's
+        self.streams = []
+
+    def request(self, _request: Request):
+        url = urlparse(_request.url)
+
+        request_headers = [
+            (':method', _request.method),
+            (':authority', url.netloc),
+            (':scheme', url.scheme),
+            (':path', url.path),
+        ]
+
+        # TODO: Check for user-agent while testing
+        request_headers += list(_request.headers.items())
+
+        # TODO: Add support for cookies here
+
+
+
+
+
+
+    def connectionMade(self):
+        """Called by Twisted when the connection is established. We can start
+        sending some data now: we should open with the connection preamble.
+        """
+        self.conn.initiate_connection()
+        self.transport.write(self.conn.data_to_send())
+
+    def dataReceived(self, data):
+        events = self.conn.receive_data(data)
+
+        self._handle_events(events)
+
+        _data = self.conn.data_to_send()
+        if _data:
+            self.transport.write(data)
+
+    def connectionLost(self, reason):
+        """Called by Twisted when the transport connection is lost.
+        """  
+
+        for stream_id in self.streams:
+            self.conn.end_stream(stream_id)
+
+    def _handle_events(self, events):
+        """Private method which acts as a bridge between the events
+        received from the HTTP/2 data and IH2EventsHandler
+
+        Arguments:
+            events {list} -- A list of events that the remote peer
+                triggered by sending data
+        """
+        for event in events:
+            if isinstance(event, ConnectionTerminated):
+                self.connection_terminated(event)
+            elif isinstance(event, DataReceived):
+                self.data_received(event)
+            elif isinstance(event, ResponseReceived):
+                self.response_received(event)
+            elif isinstance(event, StreamEnded):
+                self.stream_ended(event)
+            elif isinstance(event, StreamReset):
+                self.stream_reset(event)
+            elif isinstance(event, TrailersReceived):
+                self.trailers_received(event)
+            elif isinstance(event, WindowUpdated):
+                self.window_updated(event)
+
+    def connection_terminated(self, event):
+        pass
+
+    def data_received(self, event):
+        pass
+
+    def response_received(self, event):
+        pass
+
+    def stream_ended(self, event):
+        pass
+
+    def stream_reset(self, event):
+        pass
+
+    def trailers_received(self, event):
+        pass
+
+    def window_updated(self, event):
+        pass