WebSocket Pepper API: C++ utility class implementation.

ppapi/utility/websocket/websocket_api.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 PPAPI_UTILITY_WEBSOCKET_WEBSOCKET_API_H_
+#define PPAPI_UTILITY_WEBSOCKET_WEBSOCKET_API_H_
+
+#include "ppapi/c/ppb_websocket.h"
+
+/// @file
+/// This file defines the WebSocketAPI interface.
+
+namespace pp {
+
+class CompletionCallback;
+class Instance;
+class Var;
+
+/// The <code>WebSocketAPI</code> class
+class WebSocketAPI {
+ public:
+  /// Constructs a WebSocketAPI object.
+  explicit WebSocketAPI(Instance* instance);
+
+  /// Destructs a WebSocketAPI object.
+  virtual ~WebSocketAPI();
+
+  /// Connect() connects to the specified WebSocket server. Caller can call
+  /// this method at most once.
+  ///
+  /// @param[in] url A <code>Var</code> of string type representing a WebSocket
+  /// server URL.
+  /// @param[in] protocols A pointer to an array of string type
+  /// <code>Var</code> specifying sub-protocols. Each <code>Var</code>
+  /// represents one sub-protocol and its <code>PP_VarType</code> must be
+  /// <code>PP_VARTYPE_STRING</code>. This argument can be null only if
+  /// <code>protocol_count</code> is 0.
+  /// @param[in] protocol_count The number of sub-protocols in
+  /// <code>protocols</code>.
+  ///
+  /// @return An int32_t containing an error code from
+  /// <code>pp_errors.h</code>.
+  /// See also <code>pp::WebSocket::Connect</code>.
+  int32_t Connect(const Var& url, const Var protocols[],
+                  uint32_t protocol_count);
+
+  /// Close() closes the specified WebSocket connection by specifying
+  /// <code>code</code> and <code>reason</code>.
+  ///
+  /// @param[in] code The WebSocket close code. Ignored if it is 0.
+  /// @param[in] reason A <code>Var</code> of string type which represents the
+  /// WebSocket close reason. Ignored if it is undefined type.
+  ///
+  /// @return An int32_t containing an error code from
+  /// <code>pp_errors.h</code>.
+  /// See also <code>pp::WebSocket::Close</code>.
+  int32_t Close(uint16_t code, const Var& reason);
+
+  /// Send() sends a message to the WebSocket server.
+  ///
+  /// @param[in] data A message to send. The message is copied to internal
+  /// buffer. So caller can free <code>data</code> safely after returning
+  /// from the function.
+  ///
+  /// @return An int32_t containing an error code from
+  /// <code>pp_errors.h</code>.
+  /// See also <code>pp::WebSocket::SendMessage</code>.
+  int32_t Send(const Var& data);
+
+  /// GetBufferedAmount() returns the number of bytes of text and binary
+  /// messages that have been queued for the WebSocket connection to send but
+  /// have not been transmitted to the network yet.
+  ///
+  /// @return Returns the number of bytes.
+  uint64_t GetBufferedAmount();
+
+  /// GetExtensions() returns the extensions selected by the server for the
+  /// specified WebSocket connection.
+  ///
+  /// @return Returns a <code>Var</code> of string type. If called before the
+  /// connection is established, its data is empty string.
+  /// Currently its data is always an empty string.
+  Var GetExtensions();
+
+  /// GetProtocol() returns the sub-protocol chosen by the server for the
+  /// specified WebSocket connection.
+  ///
+  /// @return Returns a <code>Var</code> of string type. If called before the
+  /// connection is established, it contains the empty string.
+  Var GetProtocol();
+
+  /// GetReadyState() returns the ready state of the specified WebSocket
+  /// connection.
+  ///
+  /// @return Returns <code>PP_WEBSOCKETREADYSTATE_INVALID</code> if called
+  /// before connect() is called.
+  PP_WebSocketReadyState GetReadyState();
+
+  /// GetURL() returns the URL associated with specified WebSocket connection.
+  ///
+  /// @return Returns a <code>Var</code> of string type. If called before the
+  /// connection is established, it contains the empty string.
+  Var GetURL();
+
+  /// DidOpen() is invoked when the connection is established by Connect().

[dmichael (off chromium), 2012/02/14 17:59:57]

Sorry for being wishy-washy about the names. Since this is meant to be inherited
from, maybe they should be more specific to avoid clashes or confusion in
derived classes? In particular, I like "HandleMessage" because it is consistent,
but it is exactly the same name and signature as the one in pp::Instance for
receiving messages from JavaScript.

What do you think of:
SocketDidOpen
SocketDidClose
HandleSocketMessage
HandleSocketError
?

[Takashi Toyoshima, 2012/02/23 07:15:09]

I agree with the namespace issue on inheritance.

I prefer WebSocket than just Socket as a signature word because Socket is a
little generic and sometime confusing for WebSocket. 'WebSocket' is a little
long word in many situation, but 'Ws' is too short and not so clear. And
'Socket' is confusing.

+  virtual void DidOpen() = 0;
+
+  /// DidClose() is invoked when the connection is closed by errors or Close().
+  virtual void DidClose(bool wasClean, uint16_t code, const Var& reason) = 0;
+
+  /// HandleMessage() is invoked when a message is received.
+  virtual void HandleMessage(const Var& message) = 0;
+
+  /// HandleError() is invoked if the user agent was required to fail the
+  /// WebSocket connection or the WebSocket connection is closed with
+  /// prejudice. DidClose() always follows HandleError().
+  virtual void HandleError() = 0;
+
+ private:
+  class Implement;
+  Implement* impl_;
+};
+
+}  // namespace pp
+
+#endif  // PPAPI_UTILITY_WEBSOCKET_WEBSOCKET_API_H_