<link>http://people.skolelinux.org/pere/blog/</link>
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+ <item>
+ <title>CasparCG Server for TV broadcast playout in Debian</title>
+ <link>http://people.skolelinux.org/pere/blog/CasparCG_Server_for_TV_broadcast_playout_in_Debian.html</link>
+ <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/CasparCG_Server_for_TV_broadcast_playout_in_Debian.html</guid>
+ <pubDate>Tue, 15 Jan 2019 00:10:00 +0100</pubDate>
+ <description><p>The layered video playout server created by Sveriges Television,
+<a href="https://casparcg.com/">CasparCG Server</a>, entered Debian
+today. This completes many months of work to get the source ready to
+go into Debian. The first upload to the Debian NEW queue happened a
+month ago, but the work upstream to prepare it for Debian started more
+than two and a half month ago. So far
+<a href="https://tracker.debian.org/pkg/casparcg-server">the
+casparcg-server package</a> is only available for amd64, but I hope
+this can be improved. The package is in contrib because it depend on
+the <a href="https://tracker.debian.org/pkg/fdk-aac">non-free fdk-aac
+library</a>. The Debian package lack support for streaming web pages
+because Debian is missing CEF, Chromium Embedded Framework. CEF is
+wanted by several packages in Debian. But because the Chromium source
+is <a href="https://bugs.debian.org/893448">not available as a build
+dependency</a>, it is not yet possible to upload CEF to Debian. I
+hope this will change in the future.</p>
+
+<p>The reason I got involved is that
+<a href="https://frikanalen.no/">the Norwegian open channel
+Frikanalen</a> is starting to use CasparCG for our HD playout, and I
+would like to have all the free software tools we use to run the TV
+channel available as packages from the Debian project. The last
+remaining piece in the puzzle is Open Broadcast Encoder, but it depend
+on quite a lot of patched libraries which would have to be included in
+Debian first.</p>
+</description>
+ </item>
+
+ <item>
+ <title>Learn to program with Minetest on Debian</title>
+ <link>http://people.skolelinux.org/pere/blog/Learn_to_program_with_Minetest_on_Debian.html</link>
+ <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Learn_to_program_with_Minetest_on_Debian.html</guid>
+ <pubDate>Sat, 15 Dec 2018 15:30:00 +0100</pubDate>
+ <description><p>A fun way to learn how to program
+<a href="https://www.python.org/">Python</a> is to follow the
+instructions in the book
+"<a href="https://nostarch.com/programwithminecraft">Learn to program
+with Minecraft</a>", which introduces programming in Python to people
+who like to play with Minecraft. The book uses a Python library to
+talk to a TCP/IP socket with an API accepting build instructions and
+providing information about the current players in a Minecraft world.
+The TCP/IP API was first created for the Minecraft implementation for
+Raspberry Pi, and has since been ported to some server versions of
+Minecraft. The book contain recipes for those using Windows, MacOSX
+and Raspian. But a little known fact is that you can follow the same
+recipes using the free software construction game
+<a href="https://minetest.net/">Minetest</a>.</p>
+
+<p>There is <a href="https://github.com/sprintingkiwi/pycraft_mod">a
+Minetest module implementing the same API</a>, making it possible to
+use the Python programs coded to talk to Minecraft with Minetest too.
+I
+<a href="https://ftp-master.debian.org/new/minetest-mod-pycraft_0.20%2Bgit20180331.0376a0a%2Bdfsg-1.html">uploaded
+this module</a> to Debian two weeks ago, and as soon as it clears the
+FTP masters NEW queue, learning to program Python with Minetest on
+Debian will be a simple 'apt install' away. The Debian package is
+maintained as part of the Debian Games team, and
+<a href="https://salsa.debian.org/games-team/unfinished/minetest-mod-pycraft">the
+packaging rules</a> are currently located under 'unfinished' on
+Salsa.</p>
+
+<p>You will most likely need to install several of the Minetest
+modules in Debian for the examples included with the library to work
+well, as there are several blocks used by the example scripts that are
+provided via modules in Minetest. Without the required blocks, a
+simple stone block is used instead. My initial testing with a analog
+clock did not get gold arms as instructed in the python library, but
+instead used stone arms.</p>
+
+<p>I tried to find a way to add the API to the desktop version of
+Minecraft, but were unable to find any working recipes. The
+<a href="https://www.epiphanydigest.com/tag/minecraft-python-api/">recipes</a>
+I <a href="https://github.com/kbsriram/mcpiapi">found</a> are only
+working with a standalone Minecraft server setup. Are there any
+options to use with the normal desktop version?</p>
+
+<p>As usual, if you use Bitcoin and want to show your support of my
+activities, please send Bitcoin donations to my address
+<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
+</description>
+ </item>
+
<item>
<title>Non-blocking bittorrent plugin for vlc</title>
<link>http://people.skolelinux.org/pere/blog/Non_blocking_bittorrent_plugin_for_vlc.html</link>
(<a href="https://lists.nuug.no/mailman/listinfo/nikita-noark">nikita-noark
mailing list</a>).</p>
-<p>As usual, if you use Bitcoin and want to show your support of my
-activities, please send Bitcoin donations to my address
-<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
-</description>
- </item>
-
- <item>
- <title>Fetching trusted timestamps using the rfc3161ng python module</title>
- <link>http://people.skolelinux.org/pere/blog/Fetching_trusted_timestamps_using_the_rfc3161ng_python_module.html</link>
- <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Fetching_trusted_timestamps_using_the_rfc3161ng_python_module.html</guid>
- <pubDate>Mon, 8 Oct 2018 12:30:00 +0200</pubDate>
- <description><p>I have earlier covered the basics of trusted timestamping using the
-'openssl ts' client. See blog post for
-<a href="http://people.skolelinux.org/pere/blog/Public_Trusted_Timestamping_services_for_everyone.html">2014</a>,
-<a href="http://people.skolelinux.org/pere/blog/syslog_trusted_timestamp___chain_of_trusted_timestamps_for_your_syslog.html">2016</a>
-and
-<a href="http://people.skolelinux.org/pere/blog/Idea_for_storing_trusted_timestamps_in_a_Noark_5_archive.html">2017</a>
-for those stories. But some times I want to integrate the timestamping
-in other code, and recently I needed to integrate it into Python.
-After searching a bit, I found
-<a href="https://dev.entrouvert.org/projects/python-rfc3161">the
-rfc3161 library</a> which seemed like a good fit, but I soon
-discovered it only worked for python version 2, and I needed something
-that work with python version 3. Luckily I next came across
-<a href="https://github.com/trbs/rfc3161ng/">the rfc3161ng library</a>,
-a fork of the original rfc3161 library. Not only is it working with
-python 3, it have fixed a few of the bugs in the original library, and
-it has an active maintainer. I decided to wrap it up and make it
-<a href="https://tracker.debian.org/pkg/python-rfc3161ng">available in
-Debian</a>, and a few days ago it entered Debian unstable and testing.</p>
-
-<p>Using the library is fairly straight forward. The only slightly
-problematic step is to fetch the required certificates to verify the
-timestamp. For some services it is straight forward, while for others
-I have not yet figured out how to do it. Here is a small standalone
-code example based on of the integration tests in the library code:</p>
-
-<pre>
-#!/usr/bin/python3
-
-"""
-
-Python 3 script demonstrating how to use the rfc3161ng module to
-get trusted timestamps.
-
-The license of this code is the same as the license of the rfc3161ng
-library, ie MIT/BSD.
-
-"""
-
-import os
-import pyasn1.codec.der
-import rfc3161ng
-import subprocess
-import tempfile
-import urllib.request
-
-def store(f, data):
- f.write(data)
- f.flush()
- f.seek(0)
-
-def fetch(url, f=None):
- response = urllib.request.urlopen(url)
- data = response.read()
- if f:
- store(f, data)
- return data
-
-def main():
- with tempfile.NamedTemporaryFile() as cert_f,\
- tempfile.NamedTemporaryFile() as ca_f,\
- tempfile.NamedTemporaryFile() as msg_f,\
- tempfile.NamedTemporaryFile() as tsr_f:
-
- # First fetch certificates used by service
- certificate_data = fetch('https://freetsa.org/files/tsa.crt', cert_f)
- ca_data_data = fetch('https://freetsa.org/files/cacert.pem', ca_f)
-
- # Then timestamp the message
- timestamper = \
- rfc3161ng.RemoteTimestamper('http://freetsa.org/tsr',
- certificate=certificate_data)
- data = b"Python forever!\n"
- tsr = timestamper(data=data, return_tsr=True)
-
- # Finally, convert message and response to something 'openssl ts' can verify
- store(msg_f, data)
- store(tsr_f, pyasn1.codec.der.encoder.encode(tsr))
- args = ["openssl", "ts", "-verify",
- "-data", msg_f.name,
- "-in", tsr_f.name,
- "-CAfile", ca_f.name,
- "-untrusted", cert_f.name]
- subprocess.check_call(args)
-
-if '__main__' == __name__:
- main()
-</pre>
-
-<p>The code fetches the required certificates, store them as temporary
-files, timestamp a simple message, store the message and timestamp to
-disk and ask 'openssl ts' to verify the timestamp. A timestamp is
-around 1.5 kiB in size, and should be fairly easy to store for future
-use.</p>
-
-<p>As usual, if you use Bitcoin and want to show your support of my
-activities, please send Bitcoin donations to my address
-<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
-</description>
- </item>
-
- <item>
- <title>Automatic Google Drive sync using grive in Debian</title>
- <link>http://people.skolelinux.org/pere/blog/Automatic_Google_Drive_sync_using_grive_in_Debian.html</link>
- <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Automatic_Google_Drive_sync_using_grive_in_Debian.html</guid>
- <pubDate>Thu, 4 Oct 2018 15:20:00 +0200</pubDate>
- <description><p>A few days, I rescued a Windows victim over to Debian. To try to
-rescue the remains, I helped set up automatic sync with Google Drive.
-I did not find any sensible Debian package handling this
-automatically, so I rebuild the grive2 source from
-<a href="http://www.webupd8.org/">the Ubuntu UPD8 PPA</a> to do the
-task and added a autostart desktop entry and a small shell script to
-run in the background while the user is logged in to do the sync.
-Here is a sketch of the setup for future reference.</p>
-
-<p>I first created <tt>~/googledrive</tt>, entered the directory and
-ran '<tt>grive -a</tt>' to authenticate the machine/user. Next, I
-created a autostart hook in <tt>~/.config/autostart/grive.desktop</tt>
-to start the sync when the user log in:</p>
-
-<p><blockquote><pre>
-[Desktop Entry]
-Name=Google drive autosync
-Type=Application
-Exec=/home/user/bin/grive-sync
-</pre></blockquote></p>
-
-<p>Finally, I wrote the <tt>~/bin/grive-sync</tt> script to sync
-~/googledrive/ with the files in Google Drive.</p>
-
-<p><blockquote><pre>
-#!/bin/sh
-set -e
-cd ~/
-cleanup() {
- if [ "$syncpid" ] ; then
- kill $syncpid
- fi
-}
-trap cleanup EXIT INT QUIT
-/usr/lib/grive/grive-sync.sh listen googledrive 2>&1 | sed "s%^%$0:%" &
-syncpdi=$!
-while true; do
- if ! xhost >/dev/null 2>&1 ; then
- echo "no DISPLAY, exiting as the user probably logged out"
- exit 1
- fi
- if [ ! -e /run/user/1000/grive-sync.sh_googledrive ] ; then
- /usr/lib/grive/grive-sync.sh sync googledrive
- fi
- sleep 300
-done 2>&1 | sed "s%^%$0:%"
-</pre></blockquote></p>
-
-<p>Feel free to use the setup if you want. It can be assumed to be
-GNU GPL v2 licensed (or any later version, at your leisure), but I
-doubt this code is possible to claim copyright on.</p>
-
<p>As usual, if you use Bitcoin and want to show your support of my
activities, please send Bitcoin donations to my address
<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>
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