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// 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 MOJO_SHELL_DBUS_SERVICE_LOADER_H_
#define MOJO_SHELL_DBUS_SERVICE_LOADER_H_
#include <map>
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "mojo/public/cpp/system/core.h"
#include "mojo/service_manager/service_loader.h"
#include "mojo/shell/keep_alive.h"
#include "url/gurl.h"
namespace dbus {
class Bus;
} // namespace dbus
namespace mojo {
namespace shell {
class Context;
// An implementation of ServiceLoader that contacts a system service
// and bootstraps a Mojo connection to it over DBus.
//
// In order to allow the externally-running service to accept connections from
// a Mojo shell, we need to get it a ShellHandle. This class creates a
// dedicated MessagePipe, passes a handle to one end to the desired service
// over DBus, and then passes the ShellHandle over that pipe.
//
// This class assumes the following:
// 1) Your service is already running.
// 2) Your service implements the Mojo ExternalService API
// (from external_service.mojom).
// 3) Your service exports an object that implements the org.chromium.Mojo DBus
// interface:
// <interface name="org.chromium.Mojo">
// <method name="ConnectChannel">
// <arg type="h" name="file_descriptor" direction="in" />
// </method>
// </interface>
class DBusServiceLoader : public ServiceLoader {
public:
DBusServiceLoader(Context* context);
virtual ~DBusServiceLoader();
// URL for DBus services are of the following format:
// dbus:tld.domain.ServiceName/path/to/DBusObject
//
// This is simply the scheme (dbus:) and then the DBus service name followed
// by the DBus object path of an object that implements the org.chromium.Mojo
// interface as discussed above.
//
// Example:
// dbus:org.chromium.EchoService/org/chromium/MojoImpl
//
// This will tell DBusServiceLoader to reach out to a service with
// the name "org.chromium.EchoService" and invoke the method
// "org.chromium.Mojo.ConnectChannel" on the object exported at
// "/org/chromium/MojoImpl".
virtual void LoadService(ServiceManager* manager,
const GURL& url,
ScopedMessagePipeHandle shell_handle) OVERRIDE;
virtual void OnServiceError(ServiceManager* manager, const GURL& url)
OVERRIDE;
private:
class LoadContext;
// Tosses out connection-related state to service at given URL.
void ForgetService(const GURL& url);
Context* const context_;
scoped_refptr<dbus::Bus> bus_;
typedef std::map<GURL, LoadContext*> LoadContextMap;
LoadContextMap url_to_load_context_;
DISALLOW_COPY_AND_ASSIGN(DBusServiceLoader);
};
} // namespace shell
} // namespace mojo
#endif // MOJO_SHELL_DBUS_SERVICE_LOADER_H_