Make it possible to have multiple InspectorBackends

sky/services/inspector/server.cc

 // 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.
 
+#include "base/lazy_instance.h"
 #include "mojo/application/application_runner_chromium.h"
 #include "mojo/public/c/system/main.h"
 #include "mojo/public/cpp/application/application_delegate.h"
 #include "mojo/public/cpp/application/application_impl.h"
+#include "net/server/http_server.h"
+#include "net/socket/tcp_server_socket.h"
 #include "sky/services/inspector/inspector_frontend_impl.h"
 
 namespace sky {
 namespace inspector {
 
-class Server : public mojo::ApplicationDelegate {
+namespace {
+const int kNotConnected = -1;
+}
+
+class ServerImpl : public mojo::InterfaceImpl<InspectorServer> {
+public:
+  class Delegate {
+  public:
+    virtual void SetImpl(ServerImpl* impl) = 0;
+    virtual void Listen(int32_t port) = 0;
+  };
+  ServerImpl(Delegate* delegate) : delegate_(delegate) {
+    delegate_->SetImpl(this);

[Aaron Boodman, 2014/11/11 16:12:50]

If two InspectorServer interfaces are requested, the first one will leak.

In general, I think it should be mojo style to support any number of
connections. Providers shouldn't make assumptions about the number of
connections they will receive.

[eseidel, 2014/11/11 18:15:26]

Done.

+  }
+  ~ServerImpl() {
+    delegate_->SetImpl(nullptr);
+  }
+  void OnShutdown() {
+    delete this;
+  }
+
+  // InspectorServer:
+  void Listen(int32_t port, const mojo::Callback<void()>& callback) override;
+
+private:
+  // InterfaceImpl:
+  void OnConnectionError() override {
+    delete this;

[Aaron Boodman, 2014/11/11 16:12:50]

If you are just going to delete yourself on error, then you may as well use
BindToPipe rather than WeakBindToPipe.

[eseidel, 2014/11/11 18:15:26]

I can't, unfortunately, since then I can't hae the server delete the impl while
the pipe is still open.  crbug.com/431911

+  }
+
+  Delegate* delegate_;
+};
+
+class Server : public mojo::ApplicationDelegate,
+    public InspectorFrontendImpl::Delegate,
+    public ServerImpl::Delegate,
+    public mojo::InterfaceFactory<InspectorFrontendImpl>,
+    public mojo::InterfaceFactory<ServerImpl>,
+    public net::HttpServer::Delegate {
  public:
-  Server() {}
-  virtual ~Server() {}
+  Server() : connection_id_(kNotConnected) {}
+  virtual ~Server();
 
  private:
-  // Overridden from mojo::ApplicationDelegate:
-  virtual void Initialize(mojo::ApplicationImpl* app) override {
+  // mojo::ApplicationDelegate:
+  void Initialize(mojo::ApplicationImpl* app) override {
   }
-
-  virtual bool ConfigureIncomingConnection(
+  bool ConfigureIncomingConnection(
       mojo::ApplicationConnection* connection) override {
-    connection->AddService(&frontend_factory_);
+    connection->AddService(this);
     return true;
   }
 
-  InspectorFrontendFactory frontend_factory_;
+  // InterfaceFactory<InspectorFrontendImpl>:
+  void Create(mojo::ApplicationConnection* connection,
+        mojo::InterfaceRequest<InspectorFrontendImpl> request) override {
+    printf("Create InspectorFrontendImpl\n");
+    WeakBindToRequest(new InspectorFrontendImpl(this), &request);
+  }
+
+  // InterfaceFactory<InspectorServer>:
+  void Create(mojo::ApplicationConnection* connection,
+        mojo::InterfaceRequest<ServerImpl> request) override {
+    printf("Create ServerImpl\n");
+    WeakBindToRequest(new ServerImpl(this), &request);
+  }
+
+  // ServerImpl::Delegate:
+  void SetImpl(ServerImpl* server_impl) override {
+    server_impl_ = server_impl;
+  }
+  void Listen(int32_t port) override;
+
+  // InspectorFrontendImpl::Delegate:
+  void Register(InspectorFrontendImpl*) override;
+  void Unregister(InspectorFrontendImpl*) override;
+
+  void SendMessage(const mojo::String& message) override;
+
+  // From net::HttpServer::Delegate
+  void OnConnect(int connection_id) override;
+  void OnHttpRequest(
+      int connection_id, const net::HttpServerRequestInfo& info) override;
+  void OnWebSocketRequest(
+      int connection_id, const net::HttpServerRequestInfo& info) override;
+  void OnWebSocketMessage(
+      int connection_id, const std::string& data) override;
+  void OnClose(int connection_id) override;
+
+  void CloseAllAgentConnections();
+
+  int connection_id_;
+  scoped_ptr<net::HttpServer> web_server_;
+  // TODO(eseidel): The server should control the lifetime of these agents.
+  ObserverList<InspectorFrontendImpl> agents_;
+  ServerImpl* server_impl_;
 
   DISALLOW_COPY_AND_ASSIGN(Server);
 };
 
+Server::~Server()
+{
+  CloseAllAgentConnections();
+}
+
+void Server::CloseAllAgentConnections() {
+  FOR_EACH_OBSERVER(InspectorFrontendImpl, agents_, OnShutdown());
+  server_impl_->OnShutdown();
+}
+
+void Server::OnConnect(int connection_id) {
+}
+
+void Server::OnHttpRequest(
+    int connection_id, const net::HttpServerRequestInfo& info) {
+  web_server_->Send500(connection_id, "websockets protocol only");
+}
+
+void Server::OnWebSocketRequest(
+    int connection_id, const net::HttpServerRequestInfo& info) {
+  if (connection_id_ != kNotConnected) {
+    web_server_->Close(connection_id);
+    return;
+  }
+  web_server_->AcceptWebSocket(connection_id, info);
+  connection_id_ = connection_id;
+  FOR_EACH_OBSERVER(InspectorFrontendImpl, agents_, client()->OnConnect());
+}
+
+void Server::OnWebSocketMessage(
+    int connection_id, const std::string& data) {
+  DCHECK_EQ(connection_id, connection_id_);
+  printf("OnWebSocketMessage\n");
+  FOR_EACH_OBSERVER(InspectorFrontendImpl, agents_, client()->OnMessage(data));
+}
+
+void Server::OnClose(int connection_id) {
+  if (connection_id != connection_id_)
+    return;
+  connection_id_ = kNotConnected;
+  FOR_EACH_OBSERVER(InspectorFrontendImpl, agents_, client()->OnDisconnect());
+}
+
+void Server::Register(InspectorFrontendImpl* agent) {
+  printf("Server::Register\n");
+  agents_.AddObserver(agent);
+}
+
+void Server::Unregister(InspectorFrontendImpl* agent) {
+  printf("Server::Unregister\n");
+  agents_.RemoveObserver(agent);
+}
+
+void ServerImpl::Listen(int32_t port, const mojo::Callback<void()>& callback) {
+  delegate_->Listen(port);
+  callback.Run();
+}
+
+void Server::Listen(int32_t port) {
+  CloseAllAgentConnections(); // Assume caller represents a new app.
+
+  // TODO(eseidel): Early-out here if we're already bound to the right port.
+  web_server_.reset();
+  scoped_ptr<net::ServerSocket> server_socket(
+      new net::TCPServerSocket(NULL, net::NetLog::Source()));
+  server_socket->ListenWithAddressAndPort("0.0.0.0", port, 1);
+  web_server_.reset(new net::HttpServer(server_socket.Pass(), this));
+}
+
+void Server::SendMessage(const mojo::String& message) {
+  if (connection_id_ == kNotConnected)
+    return;
+  web_server_->SendOverWebSocket(connection_id_, message);
+}
+
 }  // namespace inspector
 }  // namespace sky
 
 MojoResult MojoMain(MojoHandle shell_handle) {
   mojo::ApplicationRunnerChromium runner(new sky::inspector::Server);
   runner.set_message_loop_type(base::MessageLoop::TYPE_IO);
   return runner.Run(shell_handle);
 }