Added a net::BidirectionalStream to expose a bidirectional streaming interface

net/http/bidirectional_stream_create_helper.h

Index: net/http/bidirectional_stream_create_helper.h
diff --git a/net/http/bidirectional_stream_create_helper.h b/net/http/bidirectional_stream_create_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..514bb712e560a952a3708d46cc63eb611d3e068a
--- /dev/null
+++ b/net/http/bidirectional_stream_create_helper.h
@@ -0,0 +1,102 @@
+// Copyright 2015 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_BIDIRECTIONAL_STREAM_CREATE_HELPER_H_
+#define NET_HTTP_BIDIRECTIONAL_STREAM_CREATE_HELPER_H_
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "net/base/request_priority.h"
+#include "net/http/http_stream_factory.h"
+#include "net/log/net_log.h"
+#include "net/ssl/ssl_config.h"
+
+namespace net {
+
+class BidirectionalStream;
+class ClientSocketHandle;
+class HttpAuthController;
+class HttpNetworkSession;
+class HttpStream;
+class HttpStreamRequest;
+class IOBuffer;
+class ProxyInfo;
+struct HttpRequestInfo;
+
+// A helper class to create a net::BidirectionalStream. Embedder should use
+// the Delegate interface to get notified of success or failure.

[mmenke, 2015/10/21 22:40:16]

Should mention that both the BidirectionalStreamCreateHelper and any streams it
returns must be torn down before the URLRequestContext (HttpNetworkSession?  See
below comment)

[xunjieli, 2015/10/22 20:01:41]

Done.

+class NET_EXPORT BidirectionalStreamCreateHelper
+    : public HttpStreamRequest::Delegate {
+ public:
+  class NET_EXPORT Delegate {

[mmenke, 2015/10/21 22:40:16]

Should document this - in particular, are callbacks guaranteed to be called
asynchronously?

[xunjieli, 2015/10/22 20:01:41]

Done.

+   public:
+    Delegate() {}
+
+    virtual void OnStreamCreated() = 0;
+    // |error| is a net error.
+    virtual void OnStreamFailed(int error) = 0;
+
+   protected:
+    virtual ~Delegate() {}
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Delegate);
+  };
+
+  BidirectionalStreamCreateHelper(const HttpRequestInfo* request_info,

[mmenke, 2015/10/21 22:40:16]

Worth mentioning that parts of request_info are ignored (upload_data_stream and
most load flags?  Could even DCHECK that the upload data stream is NULL, and
most load flags aren't set).

[mmenke, 2015/10/21 22:40:16]

const HttpRequestInfo& request_info?

[xunjieli, 2015/10/22 20:01:41]

Done.

[xunjieli, 2015/10/22 20:01:41]

Done.

+                                  RequestPriority priority,
+                                  const URLRequestContext* context,

[mmenke, 2015/10/21 22:40:16]

Maybe just take an HTTP network session?  That allows not having to create an
entire network stack to use it - not that I see anyone doing that, but we don't
require anything above the stream factory.

[mmenke, 2015/10/21 22:40:16]

"const" is kinda weird here - by making a request, we do basically modify the
context.

[xunjieli, 2015/10/22 20:01:41]

Done.

[xunjieli, 2015/10/22 20:01:41]

Done.

+                                  Delegate* delegate);
+
+  ~BidirectionalStreamCreateHelper() override;

[mmenke, 2015/10/21 22:40:16]

Should mention somewhere that destroying it cancels any pending request.

[xunjieli, 2015/10/22 20:01:41]

Done.

+
+  // Starts a HttpStreamRequest to create a BidirectionalStream.
+  void CreateBidirectionalStream();

[mmenke, 2015/10/21 22:40:16]

Should we do this automatically on creation?  Saves us from having to worry
about this method being called twice.

[xunjieli, 2015/10/22 20:01:41]

Done. Good idea

+
+  // HttpStreamRequest::Delegate methods:
+  void OnStreamReady(const SSLConfig& used_ssl_config,
+                     const ProxyInfo& used_proxy_info,
+                     HttpStream* stream) override;
+  void OnBidirectionalStreamReady(const SSLConfig& used_ssl_config,
+                                  const ProxyInfo& used_proxy_info,
+                                  BidirectionalStream* stream) override;
+  void OnWebSocketHandshakeStreamReady(
+      const SSLConfig& used_ssl_config,
+      const ProxyInfo& used_proxy_info,
+      WebSocketHandshakeStreamBase* stream) override;
+  void OnStreamFailed(int status,
+                      const SSLConfig& used_ssl_config,
+                      SSLFailureState ssl_failure_state) override;
+  void OnCertificateError(int status,
+                          const SSLConfig& used_ssl_config,
+                          const SSLInfo& ssl_info) override;
+  void OnNeedsProxyAuth(const HttpResponseInfo& response_info,
+                        const SSLConfig& used_ssl_config,
+                        const ProxyInfo& used_proxy_info,
+                        HttpAuthController* auth_controller) override;
+  void OnNeedsClientAuth(const SSLConfig& used_ssl_config,
+                         SSLCertRequestInfo* cert_info) override;
+  void OnHttpsProxyTunnelResponse(const HttpResponseInfo& response_info,
+                                  const SSLConfig& used_ssl_config,
+                                  const ProxyInfo& used_proxy_info,
+                                  HttpStream* stream) override;
+
+ private:
+  const HttpRequestInfo* request_info_;
+  RequestPriority priority_;
+  Delegate* delegate_;
+  BoundNetLog net_log_;
+  HttpNetworkSession* session_;
+  SSLConfig server_ssl_config_;
+  SSLConfig proxy_ssl_config_;
+
+  scoped_ptr<HttpStreamRequest> stream_request_;
+  scoped_ptr<BidirectionalStream> stream_;
+
+  DISALLOW_COPY_AND_ASSIGN(BidirectionalStreamCreateHelper);
+};
+
+}  // namespace net
+
+#endif  // NET_HTTP_BIDIRECTIONAL_STREAM_CREATE_HELPER_H_