blob: 39c96de9eb396042c70fa2fa0c3ab103dc11373f [file] [log] [blame]
// Copyright 2017 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.
#include <memory>
#include <string>
#include "base/memory/weak_ptr.h"
#include "v8/include/v8.h"
namespace gin {
class Arguments;
namespace extensions {
class NativeExtensionBindingsSystem;
class ScriptContext;
struct Message;
struct MessageTarget;
struct PortId;
// A class for handling one-time message communication, including
// runtime.sendMessage and extension.sendRequest. These methods use the same
// underlying architecture as long-lived port-based communications (like
// runtime.connect), but are exposed through a simpler API.
// A basic flow will be from an "opener" (the original sender) and a "receiver"
// (the event listener), which will be in two separate contexts (and potentially
// renderer processes). The flow is outlined below:
// chrome.runtime.sendMessage( // initiates the sendMessage flow, triggering
// // SendMessage().
// {foo: bar}, // The data sent with SendMessage().
// function() { ... }); // The response callback in SendMessage().
// This creates a new opener port in the context, and posts a message to it
// with the data. The browser then dispatches this to other renderers.
// In another context, we have:
// chrome.runtime.onMessage.addListener(function(message, sender, reply) {
// ...
// reply(...);
// });
// When the renderer receives the connection message, we will create a
// new receiver port in this context via AddReceiver().
// When the message comes in, we reply with DeliverMessage() to the receiver's
// port ID.
// If the receiver replies via the reply callback, it will send a new message
// back along the port to the browser. The browser then sends this message back
// to the opener's renderer, where it is delivered via DeliverMessage().
// This concludes the one-time message flow.
class OneTimeMessageHandler {
explicit OneTimeMessageHandler(
NativeExtensionBindingsSystem* bindings_system);
// Returns true if the given context has a port with the specified id.
bool HasPort(ScriptContext* script_context, const PortId& port_id);
// Initiates a flow to send a message from the given |script_context|.
void SendMessage(ScriptContext* script_context,
const PortId& new_port_id,
const MessageTarget& target_id,
const std::string& method_name,
bool include_tls_channel_id,
const Message& message,
v8::Local<v8::Function> response_callback);
// Adds a receiving port port to the given |script_context| in preparation
// for receiving a message to post to the onMessage event.
void AddReceiver(ScriptContext* script_context,
const PortId& target_port_id,
v8::Local<v8::Object> sender,
const std::string& event_name);
// Delivers a message to the port, either the event listener or in response
// to the sender, if one exists with the specified |target_port_id|. Returns
// true if a message was delivered (i.e., an open channel existed), and false
// otherwise.
bool DeliverMessage(ScriptContext* script_context,
const Message& message,
const PortId& target_port_id);
// Disconnects the port in the context, if one exists with the specified
// |target_port_id|. Returns true if a port was disconnected (i.e., an open
// channel existed), and false otherwise.
bool Disconnect(ScriptContext* script_context,
const PortId& port_id,
const std::string& error_message);
// Helper methods to deliver a message to an opener/receiver.
bool DeliverMessageToReceiver(ScriptContext* script_context,
const Message& message,
const PortId& target_port_id);
bool DeliverReplyToOpener(ScriptContext* script_context,
const Message& message,
const PortId& target_port_id);
// Helper methods to disconnect an opener/receiver.
bool DisconnectReceiver(ScriptContext* script_context, const PortId& port_id);
bool DisconnectOpener(ScriptContext* script_context,
const PortId& port_id,
const std::string& error_message);
// Triggered when a receiver responds to a message.
void OnOneTimeMessageResponse(const PortId& port_id,
gin::Arguments* arguments);
// Triggered when the callback to reply is garbage collected.
void OnResponseCallbackCollected(ScriptContext* script_context,
const PortId& port_id);
// Called when the messaging event has been dispatched with the result of the
// listeners.
void OnEventFired(const PortId& port_id,
v8::Local<v8::Context> context,
v8::MaybeLocal<v8::Value> result);
// The associated bindings system. Outlives this object.
NativeExtensionBindingsSystem* const bindings_system_;
base::WeakPtrFactory<OneTimeMessageHandler> weak_factory_;
} // namespace extensions