Introduce RequestWebSocketStream into HttpStreamFactory

net/http/websocket_stream_base.h

+// Copyright (c) 2013 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_HTTP_WEBSOCKET_STREAM_BASE_H_
+#define NET_HTTP_WEBSOCKET_STREAM_BASE_H_
+
+// This file is placed on net/http because net/http classes depends it.
+// Since net/http can be built without linking net/websockets code,
+// you should not introduce dependency to net/websockets in this file.
+
+#include <base/basictypes.h>
+
+namespace net {
+
+class ClientSocketHandle;
+class SpdySession;
+
+// WebSocketStreamBase is the base class of WebSocketStream.
+// net/http code uses this interface to handle WebSocketStream.
+// When net/websockets code gets a WebSocketStreamBase, it should downcast
+// the object into a derived class depending on the object's type() property.

[mmenke, 2013/05/30 19:27:12]

Why will higher level code care about the type?

[yhirano, 2013/05/31 08:36:45]

WebSocketStreamBase is not in "natural" design. Most users (i.e. code in
net/websockets) should downcast it to the appropriate derived type (e.g.
WebSocketBasicStream). So I think I should explain how to downcast it.

[Adam Rice, 2013/05/31 16:46:42]

How about a virtual AsWebSocketStream method that returns a net::WebSocketStream
pointer? You can predeclare WebSocketStream so you don't need to include the
definition, and then net::WebSocketStream can override it just to return "this".
It should help to make it clear that WebSocketStream is the main interface
definition, and avoid the need for down casts.

[yhirano, 2013/05/31 18:40:06]

Cool! I will do that. Thank you!

[yhirano, 2013/06/03 04:49:58]

Done.

+class WebSocketStreamBase {
+ public:
+  // The enum describing the stream type.
+  // Each type corresponds to a WebSocketStream derived class.
+  enum StreamType {
+    // Corresponds to WebSocketBasicStream.
+    kStreamTypeBasic,
+    // Corresponds to WebSockeSpdyStream.
+    kStreamTypeSpdy
+  };
+
+  class Factory {
+   public:
+    virtual ~Factory() {}
+
+    // Create a WebSocketBasicStream.
+    // This function (or the returned object) takes the ownership
+    // of |connection|.
+    virtual WebSocketStreamBase* CreateBasicStream(
+        ClientSocketHandle* connection,
+        bool using_proxy) = 0;
+
+    // Create a WebSocketSpdyStream.
+    virtual WebSocketStreamBase* CreateSpdyStream(
+        SpdySession* session,
+        bool use_relative_url) = 0;
+  };
+
+  virtual ~WebSocketStreamBase() {}
+
+  StreamType type() const {
+    return type_;
+  }
+
+ protected:
+  explicit WebSocketStreamBase(StreamType type);
+
+ private:
+  const StreamType type_;
+  DISALLOW_COPY_AND_ASSIGN(WebSocketStreamBase);
+};
+
+}  // namespace net
+
+#endif  // NET_HTTP_WEBSOCKET_STREAM_BASE_H_