Add embedder-specific headers to HTTP CONNECT tunnel request

net/base/proxy_delegate.h

+// Copyright 2014 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_BASE_PROXY_DELEGATE_H_
+#define NET_BASE_PROXY_DELEGATE_H_
+
+#include "base/macros.h"
+#include "net/base/net_export.h"
+
+class GURL;
+
+namespace net {
+
+class HttpRequestHeaders;
+class HttpResponseHeaders;
+class HostPortPair;
+class ProxyInfo;
+class ProxyServer;
+class ProxyService;
+class URLRequest;
+
+// Delegate for setting up a connection.
+class NET_EXPORT ProxyDelegate {
+ public:
+  ProxyDelegate() {
+  }
+
+  virtual ~ProxyDelegate() {
+  }
+
+  // Called as the proxy is being resolved for |url|. Allows the delegate to
+  // override the proxy resolution decision made by ProxyService. The delegate
+  // may override the decision by modifying the ProxyInfo |result|.
+  virtual void OnResolveProxy(const GURL& url,
+                              int load_flags,
+                              const ProxyService& proxy_service,
+                              ProxyInfo* result) = 0;
+
+  // Called when use of |bad_proxy| fails due to |net_error|. |net_error| is
+  // the network error encountered, if any, and OK if the fallback was
+  // for a reason other than a network error (e.g. the proxy service was
+  // explicitly directed to skip a proxy).
+  virtual void OnFallback(const ProxyServer& bad_proxy,
+                          int net_error) = 0;
+
+  // Called after a proxy connection. Allows the delegate to read/write
+  // |headers| before they get sent out. |headers| is valid only until
+  // OnCompleted or OnURLRequestDestroyed is called for this request.
+  virtual void OnBeforeSendHeaders(URLRequest* request,
+                                   const ProxyInfo& proxy_info,
+                                   HttpRequestHeaders* headers) = 0;
+
+  // Called immediately before a proxy tunnel request is sent.
+  // Provides the embedder an opportunity to add extra request headers.
+  virtual void OnBeforeTunnelRequest(const HostPortPair& proxy_server,
+                                     HttpRequestHeaders* extra_headers) = 0;
+
+  // Called after the response headers for the tunnel request are received.
+  virtual void OnTunnelHeadersReceived(
+      const HostPortPair& origin,
+      const HostPortPair& proxy_server,
+      const HttpResponseHeaders& response_headers) = 0;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ProxyDelegate);
+};
+
+}
+
+#endif  // NET_BASE_PROXY_DELEGATE_H_