Netzflocken

Python IS awsome.

Welcome Randall Munroe, had much fun reading your strips even before!

The new firmware update, scheduled for the 4th of December, will bring AVI (MPEG-4 Part 2, Simple Profile and Advanced Simple Profile) playback to the Xbox 360.

Sony, I’m sure you have heard of Sun Tzu? Shouting out what you do next and allowing your opponent to pull the rabbit out of the hat - even worse if the rabbit is such a highly anticipated feature - is hardly found in one of the thirteen chapters of the ‘Art of War’. ;-)

Anyway, and that’s the main reason for this post, Coherence should - more or less out of the box - stream these kind of video files to both video game consoles.

via #python.de:

A contributed test in t/05_links.t creates softlinks to several directories and then deletes them to test that remove() does NOT follow the softlinks.
Unfortunately, one of the places the test links to is File::Spec::rootdir().
As a result, when the test FAILS it will recursively delete the root directory.

This happened with an innocent Perl CPAN module only a few days ago.

Ok, finding joy in another’s misfortune isn’t the greatest virtue - but anyway, it is funny and something to think about.

Update: And while thinking I recalled a paper I read years ago - Reflections on Trusting Trust by Ken Thompson. Read it!

Vergeßt Kerners Köche ;-) - am Samstag war ein etwas außer-der-reihiges BlogMeetSKa bei Maître de Cuisine Jan in Stuttgart.

Details zum äußerst leckeren BlogEat Menü sind - cui honorem, honorem - bei Jan zu finden, hier nur noch ergänzend ein Bild der etwas belebteren Tafel.

PS: Man beachte die Honigkuchenpferde - und das Wort ‘Molukkenrazzia’ war noch nicht einmal gefallen.

I’ve spend some more time on the Coherence D-Bus integration and have now reached a level where I can build a D-Bus service that resembles the structure of an UPnP device tree.

As root we have a D-Bus service org.Coherence, which can be queried for devices it knows about. The devices are sub-nodes - represented by their uuid (dashes had to be removed as D-Bus doesn’t allow them there), with their services sub-nodes of them again.

click for a larger image

I just checked in a new version of Coherence with a provisional integration of the D-Bus message bus system.

D-Bus support within Coherence will be divided into two parts:

1. accessing UPnP devices and services via D-Bus as a client
• notification about the emergence of new devices and their disappearance
• access to the API of the Coherence service clients, for instance the Browse method of the ContentDirectoryService
• signaling of UPnP service StateVariable changes
2. providing the backend functionality for an UPnP device
   There I’m think off two ways to achieve this:
• a dedicated plugin for each backend that proxies the UPnP action to their respective backend method, like we do this already for instance in the Elisa backend, using Twisted Perspective Broker as RPC protocol.
• a generic D-Bus hooking-in system, that can be used to initiate a UPnP device creation via DBus and to tell Coherence which DBus methods should be called on recieving an UPnP action request

The first part is working, lacking the signaling of the StateVariable changes though. That added it will be very,very easy to supply UPnP A/V MediaServer browsing capabilities to any D-Bus talking application. E.g. replacing the Rhythmbox Coherence UPnP plugins, which have to be in Python at the moment, with some native code.

The second one I’m still contemplating about on how to implement it in a plain and standard style, that allows an application to ask Coherence to create an UPnP device with its services - not only an A/V device, but others too, even non-standard ones - to publish so far locally restricted D-Bus services out onto the network.

^* It is no full bridge yet - at least not in my opinion, at the moment it is more looking like something really simple timbered together. ;-)

I just got informed that my proposal for a talk about Coherence at the Embedded Linux Conference - Europe 2007 was accepted!

The conference will be held in Linz/Austria during the 2nd and 3rd of November.

These are the messages you like to read when browsing your email during breakfast - even coffee tastes much better now. ;-)

Say you want to work on your favorite UPnP software en route or even present it to somebody else.

But all you have is your laptop and no network connection. And the only interface that is up and has an IP address assigned is the loopback one, good ol’ 127.0.0.1.

Now if you start two Coherence instances and they don’t see each other, that’s due to the SSDP multicast messages, which they send out to announce their presence or to search for other UPnP devices, do not reach each other.

The chances are that no IP routing is set up. That’s quite reasonable on a system with only the loopback interface active, but UPnP - to be more precise SSDP - needs it.

The solution is to add either a route for the UPnP multicast address pointing to the loopback interface:

sudo route add 239.255.255.250 lo

or more lazy universally valid, and maybe helpful for some other software on your system too, just add a default route to it:

sudo route add default lo

as multicast packages - good citizens of the IP network - will travel the default route if not explicitly told elsewise.^*

If you get networked again, do not forget to remove that route. Of course having that done automagically by e.g. the Gnome NetworkManager would be much nicer. If you know how, please leave a comment.

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^* Using a default route is acceptable in this situation, in your own LAN you better go for the UPnP multicast one, as with the default route the packages first will be send to what is mostly your internet gateway, and will be there injected again into your network.

The UPnP Implementers Corporation announced that the UPnP Device Architecture Version 1.0 and seventy-six UPnP device and service specifications have been approved as international standard.

It seems they had a lot less difficulties than some other proposal to receive the relevant amount of approval votes by the committee of the International Standards Organization.

Let’s hope that this consecration provokes the creators of UPnP devices now even more to respect that they implement a standard and that they should obey to it.

After fighting with my crashed Typo instance for a while and playing around with some other blog engines I found out about TextPress.

TextPress is a new blogging system written in Python. I decided for myself to use something Python based, as if there are any issues I at least have a change trying to extend or to fix it myself. And running PHP on my box was out of the question anyway. ;-)

It is still a pre-release, but as it is grounded on Werkzeug, Jinja and SQLAlchemy I expect it to move on pretty fast. And there is no big framework behind it, which is advantageous.

I’ll try to import my old posts now, which after COREblog, Typo and a short interlude with aether will hopefully find again a more permanent home.