Meiga shares selected local directories via web and also as an RSS feed. It can reconfigure your LAN router using UPnP to make the share accessible from the Internet. More information in http://meiga.igalia.com These slides were prepared for the Gran Canaria Desktop Summit 2009 (Thu Jul 9 2009).

1. static void
_f_do_barnacle_install_properties(GObjectClass
*gobject_class)
{
Meiga
GParamSpec *pspec;
/* Party code attribute */
pspec = g_param_spec_uint64
(F_DO_BARNACLE_CODE,
Light content sharing from the
"Barnacle code.",
"Barnacle code",
0,
G_MAXUINT64,
desktop
G_MAXUINT64 /*
default value */,
G_PARAM_READABLE
| G_PARAM_WRITABLE |
G_PARAM_PRIVATE);
g_object_class_install_property (gobject_class,
F_DO_BARNACLE_PROP_CODE,
Enrique Ocaña González
eocanha@igalia.com

2. Index
● A need: content sharing
● Development process
● The result
● How it works
● Ideas for the future
● References

3. A need: content sharing

4. Motivation
Many desktop applications use web services and
online contents
Few offer contents to other applications (P2P,
servers)
Use cases:
● Share files or pictures in an convenient way
● Be an agent that generates XML or RSS contents
which can be consumed by an external aggregation
service (planet, Yahoo pipes, etc.)
● Remotely command applications

5. Alternatives
Dedicated server technologies:
Apache+PHP, Java/Tomcat, Mono/ASP...
Desktop utilities:
Gnome-user-share
KDE File server
Opera Unite

6. Disadvantages
Dedicated server technologies:
Heavy, complex to set up
Not integrated with Gnome mainloop
Desktop utilities:
Gnome-user-share: depends on Apache (heavy)
KDE File server: Kicker applet
Opera Unite: not free software

7. Solution
Lightweight GPL application using technologies
friendly with Gnome desktop:
Based on GObject
Easy integration with main loop
Possibility of DBUS services to third parties
Simplified network configuration
Existent libraries:
libsoup
libgupnp

8. Libsoup 2.4 Libgupnp 0.6
Asynchronous, uses Glib Asynchronous, uses Glib
main loop main loop
SSL support using GNU UPnP allows to configure
TLS port dedirection if
Server basic and digest supported by the
authentication support router
SOAP and XML-RPC
basic client support

9. Initial evolution plan
Stage 1 Stage 2 Stage 3
● Evaluate libraries ● Generate RSS ● Extend some existing Gnome
feeds applications to implement
● Implement a little file functionalities such as:
server similar to ● Register more
KDE Public complex things: ● “Offer all your pictures as
Fileserver remote calls to RSS”
functions, etc.
● Code a DBUS ● “Offer the playlist of
service to allow songs you've listened
other programs to today to as RSS”
register/unregister
files for sharing Meiga está ahora
aproximadamente
aquí

10. Development process

11. Programming language
Vala was the chosen language
Advantages:
Easy to use → Less development time
Execution speed
Previous experience
Disadvantages:
Evolving syntax
There's no binding for all the libraries → Pure C
More complex autotools integration

12. Real project evolution
Release 0.1.0 Release 0.2.0
File server module

13. Real project evolution
Release 0.1.0 Release 0.2.0
File server module
DBUS interface for external applications

14. Real project evolution
Release 0.1.0 Release 0.2.0
File server module
DBUS interface for external applications
RSS server module

15. Real project evolution
Release 0.1.0 Release 0.2.0
File server module
DBUS interface for external applications
RSS server module
Graphic interface

16. Real project evolution
Release 0.1.0 Release 0.2.0
File server module
DBUS interface for external applications
RSS server module
Graphic interface
Autotools integration

17. Real project evolution
Release 0.1.0 Release 0.2.0
File server module
DBUS interface for external applications
RSS server module
Graphic interface
Autotools integration
UpnP redirection utility
Release 0.1.0

18. Real project evolution
Release 0.1.0 Release 0.2.0
File server module
DBUS interface for external applications
RSS server module
Graphic interface
Autotools integration
UpnP redirection utility
Release 0.1.0

19. Real project evolution
Release 0.1.0 Release 0.2.0
Port from Glade to GtkBuilder

20. Real project evolution
Release 0.1.0 Release 0.2.0
Port from Glade to GtkBuilder
Log exposing to the graphic interface

21. Real project evolution
Release 0.1.0 Release 0.2.0
Port from Glade to GtkBuilder
Log exposing to the graphic interface
Spanish and Galician internationalization

22. Real project evolution
Release 0.1.0 Release 0.2.0
Port from Glade to GtkBuilder
Log exposing to the graphic interface
Spanish and Galician internationalization
Bug correction

23. Real project evolution
Release 0.1.0 Release 0.2.0
Port from Glade to GtkBuilder
Log exposing to the graphic interface
Spanish and Galician internationalization
Bug correction
Release 0.2.0

24. The result

25. Home network
Router UpnP
IP: 1.2.3.4
Meiga
IP: 192.168.1.10 Internet
Contents Remote user

26. Main window and system tray

27. Log and port redirection

28. Sharing a folder

29. Sharing a folder

30. Remote access

31. Remote access

32. Contents as RSS

33. Log

34. How it works

35. SERVER
libsoup
DBUS
HTTP MeigaServer
Meiga
gui.glade
Log
GUI
Net RssFeed RssNode Gui
gui.ui
NET
fwlocalip fwupnp Test
sh C
UPnP libgupnp upnp
Router
C

36. Programmable serial asynch
events management
Composite action “redirect port” Some states are
Connect Redirect Return reused for other
composite actions
Program State interpreter
Action for state 1
E1 Action for state 2
E2
EN
Action for state N
Data Callback for state 1
Parameters Timeout control Callback for state 2
Response Callback for state N
Intermediate data
Sequence control

37. Ideas for the future

38. More redirection modules
Redirection by SSH
SERVER
SSH server
HTTP
Net Auxiliar client
NET Remote browser
fwlocalip fwssh
sh

39. Integration with other desktop
applications
Nautilus menu: “Share on Meiga”
SERVER
DBUS
MeigaServer
Meiga Third party utility

40. More server modules
Function calls
URL SERVER
DBUS Rythmbox
Playlist module
MeigaServer
/playlist/...
Evolution
/addressbook/...
Contacts module

41. Security
Password access
Cyphering
Restriction by IP
etc.

42. Situations to avoid
Meiga shouldn't become a comprehensive
interface for DBUS through HTTP (“serve
everything”)
● Security holes
● There are currently more advanced utilities for
network object sharing. Eg: CORBA

43. References

44. References
● http://meiga.igalia.com
● http://live.gnome.org/Vala
● http://library.gnome.org/devel/libsoup/stable/libsoup-server-
howto.html
● http://dbus.freedesktop.org/doc/api/html/group__DBusBus.html
● http://raphael.slinckx.net/blog/documents/dbus-tutorial
● http://www.gupnp.org/docs/gupnp/client-tutorial.html
● http://www.upnp.org/standardizeddcps/igd.asp99
● http://www.lrde.epita.fr/~adl/autotools.html
● http://live.gnome.org/Vala/GameDevelopmentSeries/Setup

45. http://meiga.igalia.com
Thank you very much
Questions, comments, suggestions?