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

net/http/bidirectional_stream_job.h

+// 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_JOB_H_
+#define NET_HTTP_BIDIRECTIONAL_STREAM_JOB_H_
+
+#include "base/macros.h"
+#include "net/base/net_export.h"
+#include "net/base/request_priority.h"
+#include "net/http/http_request_info.h"
+#include "net/spdy/spdy_session.h"
+#include "net/spdy/spdy_stream.h"
+
+namespace net {
+
+struct HttpRequestInfo;
+class IOBuffer;
+class BoundNetLog;
+
+// An interface that exposes bidirectional streaming.

[mef, 2015/11/10 23:00:27]

Maybe add a comment about lifetime scenarios that are addressed by having
BidirectionalStreamJob?

[xunjieli, 2015/11/13 23:41:45]

I am not very sure what the lifetime scenarios you have in mind. Could you
elaborate a bit? 

[xunjieli, 2015/11/25 16:58:58]

Done.

+class NET_EXPORT_PRIVATE BidirectionalStreamJob {
+ public:
+  // Delegate to handle BidirectionalStreamJob events.
+  class Delegate {
+   public:
+    Delegate();
+
+    // Called when an error occurs. E.g. when a connection to the server cannot
+    // be established.
+    virtual void OnFailed(Error error) = 0;
+
+    // Called when the request headers have been sent.
+    virtual void OnRequestHeadersSent() = 0;
+
+    // Called when response headers are received.
+    virtual void OnHeaders(const SpdyHeaderBlock& response_headers) = 0;
+
+    // Called when read is completed asynchronously. |bytes_read| specifies how
+    // much data is available.
+    virtual void OnReadCompleted(int bytes_read) = 0;
+
+    // Called when the entire buffer passed through SendData is sent.
+    virtual void OnDataSent() = 0;
+
+    // Called when trailers are received.
+    virtual void OnTrailers(const SpdyHeaderBlock& trailers) = 0;
+
+    // Called when the stream is closed. No other delegate functions will be
+    // called after this. |status| is an error code or OK.
+    virtual void OnClose(int status) = 0;
+
+   protected:
+    virtual ~Delegate();
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Delegate);
+  };
+
+  BidirectionalStreamJob();
+  virtual ~BidirectionalStreamJob();
+
+  // Starts the BidirectionalStreamJob and sends request headers.
+  virtual void Start(const HttpRequestInfo& request_info,
+                     RequestPriority priority,
+                     const BoundNetLog& net_log,
+                     Delegate* delegate) = 0;
+
+  // Reads at most |buf_len| bytes into |buf|. Returns the number of bytes read,
+  // or ERR_IO_PENDING if the read is to be completed asynchronously.
+  virtual int ReadData(IOBuffer* buf, int buf_len) = 0;
+
+  // Sends data. This should not be called again until OnDataSent is invoked.
+  virtual void SendData(IOBuffer* data, int length, bool end_stream) = 0;
+
+  // Cancels the stream. No Delegate method will be called.
+  virtual void Cancel() = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BidirectionalStreamJob);
+};
+
+}  // namespace net
+
+#endif  // NET_HTTP_BIDIRECTIONAL_STREAM_JOB_H_