relnote: Implement server push methods in QuicSimpleServerSession. Only modify toy Quic server, not…

net/tools/quic/quic_simple_server_session.cc

Index: net/tools/quic/quic_simple_server_session.cc
diff --git a/net/tools/quic/quic_simple_server_session.cc b/net/tools/quic/quic_simple_server_session.cc
index 0c6aeb876852064b61e85d2b06469539df5a6017..9b4257615e401f8e7f16a3462baeb798a5c5a64d 100644
--- a/net/tools/quic/quic_simple_server_session.cc
+++ b/net/tools/quic/quic_simple_server_session.cc
@@ -5,12 +5,14 @@
 #include "net/tools/quic/quic_simple_server_session.h"
 
 #include "base/logging.h"
+#include "base/stl_util.h"
 #include "net/quic/proto/cached_network_parameters.pb.h"
 #include "net/quic/quic_connection.h"
 #include "net/quic/quic_flags.h"
 #include "net/quic/quic_spdy_session.h"
 #include "net/quic/reliable_quic_stream.h"
 #include "net/tools/quic/quic_simple_server_stream.h"
+#include "url/gurl.h"
 
 namespace net {
 namespace tools {
@@ -20,7 +22,8 @@ QuicSimpleServerSession::QuicSimpleServerSession(
     QuicConnection* connection,
     QuicServerSessionVisitor* visitor,
     const QuicCryptoServerConfig* crypto_config)
-    : QuicServerSessionBase(config, connection, visitor, crypto_config) {}
+    : QuicServerSessionBase(config, connection, visitor, crypto_config),
+      highest_promised_stream_id_(0) {}
 
 QuicSimpleServerSession::~QuicSimpleServerSession() {}
 
@@ -30,6 +33,41 @@ QuicSimpleServerSession::CreateQuicCryptoServerStream(
   return new QuicCryptoServerStream(crypto_config, this);
 }
 
+void QuicSimpleServerSession::StreamDraining(QuicStreamId id) {
+  QuicSpdySession::StreamDraining(id);
+  if (!IsIncomingStream(id)) {
+    HandlePromisedPushRequests();
+  }
+}
+
+void QuicSimpleServerSession::OnStreamFrame(const QuicStreamFrame& frame) {
+  if (!IsIncomingStream(frame.stream_id)) {
+    LOG(WARNING) << "Client shouldn't send data on server push stream";
+    connection()->SendConnectionCloseWithDetails(
+        QUIC_INVALID_STREAM_ID, "Client sent data on server push stream");
+    return;
+  }
+  QuicSpdySession::OnStreamFrame(frame);
+}
+
+void QuicSimpleServerSession::PromisePushResources(
+    const string& request_url,
+    const list<QuicInMemoryCache::ServerPushInfo>& resources,
+    QuicStreamId original_stream_id,
+    const SpdyHeaderBlock& original_request_headers) {
+  for (QuicInMemoryCache::ServerPushInfo resource : resources) {
+    SpdyHeaderBlock headers = SynthesizePushRequestHeaders(
+        request_url, resource, original_request_headers);
+    highest_promised_stream_id_ += 2;
+    SendPushPromise(original_stream_id, highest_promised_stream_id_, headers);
+    promised_streams_.push_back(PromisedStreamInfo(
+        headers, highest_promised_stream_id_, resource.priority));
+  }
+
+  // Procese promised push request as many as possible.
+  HandlePromisedPushRequests();
+}
+
 QuicSpdyStream* QuicSimpleServerSession::CreateIncomingDynamicStream(
     QuicStreamId id) {
   if (!ShouldCreateIncomingDynamicStream(id)) {
@@ -52,5 +90,98 @@ QuicSimpleServerStream* QuicSimpleServerSession::CreateOutgoingDynamicStream(
   return stream;
 }
 
+void QuicSimpleServerSession::CloseStreamInner(QuicStreamId stream_id,
+                                               bool locally_reset) {
+  QuicSpdySession::CloseStreamInner(stream_id, locally_reset);
+  HandlePromisedPushRequests();
+}
+
+void QuicSimpleServerSession::HandleFrameOnNonexistentOutgoingStream(
+    QuicStreamId stream_id) {
+  // If this stream is a promised but not created stream (stream_id within the
+  // range of next_outgoing_stream_id_ and highes_promised_stream_id_),
+  // connection shouldn't be closed.
+  // Otherwise behave in the same way as base class.
+  if (stream_id > highest_promised_stream_id_) {
+    QuicSession::HandleFrameOnNonexistentOutgoingStream(stream_id);
+  }
+}
+
+void QuicSimpleServerSession::HandleRstOnValidNonexistentStream(
+    const QuicRstStreamFrame& frame) {
+  QuicSession::HandleRstOnValidNonexistentStream(frame);
+  if (!IsClosedStream(frame.stream_id)) {
+    // If a nonexistent stream is not a closed stream and still valid, it must
+    // be a locally preserved stream. Resetting this kind of stream means
+    // cancelling the promised server push.
+    // Since PromisedStreamInfo are queued in sequence, the corresponding
+    // index for it in promised_streams_ can be calculated.
+    DCHECK(frame.stream_id >= next_outgoing_stream_id());
+    size_t index = (frame.stream_id - next_outgoing_stream_id()) / 2;
+    DCHECK(index <= promised_streams_.size());
+    promised_streams_[index].is_cancelled = true;
+    connection()->SendRstStream(frame.stream_id, QUIC_RST_ACKNOWLEDGEMENT, 0);
+  }
+}
+
+SpdyHeaderBlock QuicSimpleServerSession::SynthesizePushRequestHeaders(
+    string request_url,
+    QuicInMemoryCache::ServerPushInfo resource,
+    const SpdyHeaderBlock& original_request_headers) {
+  GURL push_request_url = resource.request_url;
+  string path = push_request_url.path();
+
+  SpdyHeaderBlock spdy_headers = original_request_headers;
+  // :authority could be different from original request.
+  spdy_headers.ReplaceOrAppendHeader(":authority", push_request_url.host());
+  spdy_headers.ReplaceOrAppendHeader(":path", path);
+  // Push request always use GET.
+  spdy_headers.ReplaceOrAppendHeader(":method", "GET");
+  spdy_headers.ReplaceOrAppendHeader("referer", request_url);
+  spdy_headers.ReplaceOrAppendHeader(":scheme", push_request_url.scheme());
+  // It is not possible to push a response to a request that includes a request
+  // body.
+  spdy_headers.ReplaceOrAppendHeader("content-length", "0");
+  // Remove "host" field as push request is a directly generated HTTP2 request
+  // which should use ":authority" instead of "host".
+  spdy_headers.erase("host");
+  return spdy_headers;
+}
+
+void QuicSimpleServerSession::SendPushPromise(
+    QuicStreamId original_stream_id,
+    QuicStreamId promised_stream_id,
+    const SpdyHeaderBlock& headers) {
+  DVLOG(1) << "stream " << original_stream_id
+             << " send PUSH_PROMISE for promised stream " << promised_stream_id;
+  headers_stream()->WritePushPromise(original_stream_id, promised_stream_id,
+                                     headers, nullptr);
+}
+
+void QuicSimpleServerSession::HandlePromisedPushRequests() {
+  while (!promised_streams_.empty() && ShouldCreateOutgoingDynamicStream()) {
+    const PromisedStreamInfo& promised_info = promised_streams_.front();
+    DCHECK_EQ(next_outgoing_stream_id(), promised_info.stream_id);
+
+    if (promised_info.is_cancelled) {
+      // This stream has been reset by client. Skip this stream id.
+      promised_streams_.pop_front();
+      GetNextOutgoingStreamId();
+      return;
+    }
+
+    QuicSimpleServerStream* promised_stream =
+        static_cast<QuicSimpleServerStream*>(
+            CreateOutgoingDynamicStream(promised_info.priority));
+    DCHECK(promised_stream != nullptr);
+    DCHECK_EQ(promised_info.stream_id, promised_stream->id());
+    DVLOG(1) << "created server push stream " << promised_stream->id();
+
+    promised_stream->PushResponse(promised_info.request_headers);
+
+    promised_streams_.pop_front();
+  }
+}
+
 }  // namespace tools
 }  // namespace net