Add a QuicHttpStream class.

net/quic/quic_http_stream.h

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef NET_QUIC_QUIC_HTTP_STREAM_H_
+#define NET_QUIC_QUIC_HTTP_STREAM_H_
+
+#include <list>
+
+#include "base/memory/weak_ptr.h"
+#include "net/base/io_buffer.h"
+#include "net/http/http_stream.h"
+#include "net/quic/quic_reliable_client_stream.h"
+
+namespace net {
+
+// The SpdyHttpStream is a QUIC-specific HttpStream subclass.
+class NET_EXPORT_PRIVATE QuicHttpStream :
+      public QuicReliableClientStream::Delegate,
+      public HttpStream {
+ public:
+  explicit QuicHttpStream(QuicReliableClientStream* stream);
+
+  virtual ~QuicHttpStream();
+
+  // HttpStream implementation.
+  virtual int InitializeStream(const HttpRequestInfo* request_info,
+                               const BoundNetLog& net_log,
+                               const CompletionCallback& callback) OVERRIDE;
+  virtual int SendRequest(const HttpRequestHeaders& request_headers,
+                          HttpResponseInfo* response,
+                          const CompletionCallback& callback) OVERRIDE;
+  virtual UploadProgress GetUploadProgress() const OVERRIDE;
+  virtual int ReadResponseHeaders(const CompletionCallback& callback) OVERRIDE;
+  virtual const HttpResponseInfo* GetResponseInfo() const OVERRIDE;
+  virtual int ReadResponseBody(IOBuffer* buf,
+                               int buf_len,
+                               const CompletionCallback& callback) OVERRIDE;
+  virtual void Close(bool not_reusable) OVERRIDE;
+  virtual HttpStream* RenewStreamForAuth() OVERRIDE;
+  virtual bool IsResponseBodyComplete() const OVERRIDE;
+  virtual bool CanFindEndOfResponse() const OVERRIDE;
+  virtual bool IsMoreDataBuffered() const OVERRIDE;
+  virtual bool IsConnectionReused() const OVERRIDE;
+  virtual void SetConnectionReused() OVERRIDE;
+  virtual bool IsConnectionReusable() const OVERRIDE;
+  virtual void GetSSLInfo(SSLInfo* ssl_info) OVERRIDE;
+  virtual void GetSSLCertRequestInfo(
+      SSLCertRequestInfo* cert_request_info) OVERRIDE;
+  virtual bool IsSpdyHttpStream() const OVERRIDE;
+  virtual void LogNumRttVsBytesMetrics() const OVERRIDE {}
+  virtual void Drain(HttpNetworkSession* session) OVERRIDE;
+
+  // QuicReliableClientStream::Delegate implementation
+  virtual int OnSendData() OVERRIDE;
+  virtual int OnSendDataComplete(int status, bool* eof) OVERRIDE;
+  virtual int OnDataReceived(const char* data, int length) OVERRIDE;
+  virtual void OnClose(QuicErrorCode error) OVERRIDE;
+
+ private:
+  enum State {
+    STATE_NONE,
+    STATE_SEND_HEADERS,
+    STATE_SEND_HEADERS_COMPLETE,
+    STATE_READ_REQUEST_BODY,
+    STATE_READ_REQUEST_BODY_COMPLETE,
+    STATE_SEND_BODY,
+    STATE_OPEN,
+  };
+
+  void OnIOComplete(int rv);
+  void DoCallback(int rv);
+
+  int DoLoop(int);
+  int DoSendHeaders();
+  int DoSendHeadersComplete(int rv);
+  int DoReadRequestBody();
+  int DoReadRequestBodyComplete(int rv);
+  int DoSendBody(int rv);
+  int DoReadResponseHeaders();
+  int DoReadResponseHeadersComplete(int rv);
+
+  int ParseResponseHeaders();
+
+  void BufferResponseBody(const char* data, int length);
+
+  State io_state_;
+
+  QuicReliableClientStream* stream_;  // Non-owning.

[willchan no longer on Chromium, 2012/11/21 23:07:04]

Is there a comment somewhere that describes the ownership relationships between
the core classes, as we discussed offline in person & email? That would help a
lot as a class or file level comment.

[Ryan Hamilton, 2012/11/21 23:35:09]

There is not.  I'll update the comments in the header files.

+
+  // The request to send, onder by the caller.
+  const HttpRequestInfo* request_info_;

[willchan no longer on Chromium, 2012/11/21 23:07:04]

This is also non-owning. I think that this must outlive the stream is part of
the HttpStream contract, but was never really documented. Perhaps updating
http_stream.h to document this would be great.

[Ryan Hamilton, 2012/11/21 23:35:09]

updated http_stream_base.h

+  // Serialized HTTP request.
+  std::string request_;

[willchan no longer on Chromium, 2012/11/21 23:07:04]

I can't seem to find where this gets used. What's it for?

[Ryan Hamilton, 2012/11/21 23:35:09]

It is the serialized HTTP request which is created in SendRequest and used
(later) in DoSendHeaders.  (Soon I'll switch to a SPDY serialization for the
request, so this will likely change).

+
+  // The request body to send, if any, owned by the caller.

[willchan no longer on Chromium, 2012/11/21 23:07:04]

Like HttpRequestInfo, we should document this in the HttpStream contract.

[Ryan Hamilton, 2012/11/21 23:35:09]

Updated http_stream_base.h

+  UploadDataStream* request_body_stream_;
+
+  // |response_info_| is the HTTP response data object which is filled in
+  // when a the reponse headers are read.  It is not owned by this stream.

[willchan no longer on Chromium, 2012/11/21 23:07:04]

s/reponse/response/
Again, document ownership in HttpStream contract.

Perhaps group all of these together with a block comment saying this group of
variables is owned by the consumer of HttpStream.

[Ryan Hamilton, 2012/11/21 23:35:09]

Done.

+  HttpResponseInfo* response_info_;
+  bool response_headers_received_;
+
+  // Buffer into which response header data is read.
+  scoped_refptr<GrowableIOBuffer> read_buf_;

[willchan no longer on Chromium, 2012/11/21 23:07:04]

I really hate GrowableIOBuffer and DrainableIOBuffer. They exist for good
reasons, since we needed to provide things compatible with the IOBuffer
interface. If you don't need that, I'd prefer if you don't use these classes.

Push back since you understand project priorities here better than I, but I'm
concerned about these classes in particular, because they have a tendency to
leak out through APIs, so it might take nontrivial time to fix later on. At this
level, we need to be very careful about buffer management to reduce copies, so
these classes are very important.

I don't have time to think about it right now, but you probably do :) Please
consider this, and if you're comfortable with it, we can keep it as is.

[Ryan Hamilton, 2012/11/21 23:35:09]

Well, I definitely don't *need* GrowableIOBuffer, but it's *really* convenient. 
In order to make use of the existing HTTP response parsing code, I need to have
the complete HTTP response in a single block of memory.  The GrowableIOBuffer
seems to be ideal for this.  

Good point about the need to avoid buffer copies.  I wasn't thinking yet about
the performance.  Eventually (soon) i'll rip out the HTTP parsing and replace it
with SPDY parsing.  When that happen we won't need this buffer at all (Since
we'll simply send it to a SpdyFramer).  Is it ok to keep it around for now?

+
+  // We buffer the response body as it arrives asynchronously from the stream.
+  // TODO(rch): This is infinite buffering, which is bad.
+  std::list<scoped_refptr<IOBufferWithSize> > response_body_;
+
+  // The caller's callback to be used for asynchronous operations.
+  CompletionCallback callback_;
+
+  // Caller provided buffer for the ReadResponseBody() response.
+  scoped_refptr<IOBuffer> user_buffer_;
+  int user_buffer_len_;
+
+  // Temporary buffer used to read the request body from UploadDataStream.
+  scoped_refptr<IOBufferWithSize> raw_request_body_buf_;
+  // Wraps raw_request_body_buf_ to read the remaining data progressively.
+  scoped_refptr<DrainableIOBuffer> request_body_buf_;
+
+  base::WeakPtrFactory<QuicHttpStream> weak_factory_;
+};
+
+}  // namespace net
+
+#endif  // NET_QUIC_QUIC_HTTP_STREAM_H_