Posts about python

Converting latin-1 To utf-8 with Python

Tonight I finally converted all the Glossary pages in my mirror of the Jargon File into Unicode (utf-8 encoding) so that they will transmit and display properly from GitHub Pages (or any other modern web server). It was a fairly trivial thing to do in the end, but I am likely to need to repeat this for other things at work, so I'm blogging it.

The Jargon File was converted into XML-Dockbook and Unicode for version 4.4.0, but ESR only converted the front- and back-matter, not the Glossary entries (i.e. the actual lexicon). Those are still latin-1 (ISO-8859-1). And although the HTML rendition begins with the correct header declaring this:

<?xml version="1.0" encoding="ISO-8859-1" standalone="no"?>

The pages are actually served from as Unicode (utf-8). For instance, compare /dev/null on with my mirror of /dev/null.

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Journald experiments - Testing systemd's logger: speed and buffering

I've been having good natured arguments at work about whether it's the End of the World that we are at last switching away from Scientific Linux 6 and it's System V style init scripts, to CentOS 7, which uses systemd.

My own opinion is that systemd is pretty cuspy. It's not perfect, but nor is it some great hulking monolithic monster come to destroy the Unix Way in the Linux world. It offers many worthwhile improvements and I've enjoyed using it in openSUSE for years now. I look forward to switching away from the hair-ball of wet SysV init scripts with clumsy precedent semantics and manual service recovery.

Now, I don't want to throw my hat into the ring on the pro's and con's of systemd having replaced the start-up infrastructure (and a lot of other systems besides) on Linux-based operating systems. Enough has been said already on that front, by many more experienced than I, and further argument is pointless: whichever camp you're in, you won't be convinced of the other sides point of view by now.

However there is one argument against systemd that I'm not so sure about: journald and it's past issues:

  • alleged buffering of logs, making diagnostics and debugging on time-critical services difficult or impossible
  • binary log files which can be corrupted, and then not useful thereafter (because they're binary)
  • volatile storage, so that your logs are gone when you want them the most: after an unplanned reboot

I'll be spending a few days experimenting with journald in these areas, to see if it's as bad now as it was five years ago when concerns like these were being raised.

In this post I want to look at the journald daemon / journalctl log viewer a bit, from the point of view of buffering output, whether and where it could be occurring, and what the implications might be as a web sysop.

This is a medium-long post, with about 23 minutes of terminal output recordings (in text, using asciinema) and is about 2⅓MB to download. It's also about half-an-hour's read on top of that.

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Exploring Minecraft code in Jupyter

Some breif notes from a lazy Sunday morning spent exploring the minecraft coding environment that I set up using Raspberry Jam earlier. I'm taking my notes in Jupyter while I explore the Minecraft API and poke around with one of the sample programs. Since my blogging engine Nikola also supports Jupyter Notebooks as one of it's import formats, I found that I could do Litterate Programming for Minecraft quite nicely!

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Hacking Minecraft with Python

I'm having a play with Minecraft and Python, using the mcpipy library, a Minecraft server called CannaryMod, and a plugin-in for that called RaspberryJuice.

You can do all this out-of-the-box with Raspbian on a RaspberryPi, but I wanted to set up my home computers also. Here's a quick run-down of the steps I followed.

NetBeans 6.5 and Python

NetBeans 6.5 is out! You can run it with the Nimbus look and feel too! There's also an Early Access plugin for Python. All very nice.

I recently had occasion to play with some Python at work (a small script to do some configurations, and I didn't want to do them in bash), so I took the time to get all of this set up. It's all so very easy and not worth writing about. However I thought that the interactive debugger (which is awesome, btw) has a small issue that needs resolving. Mean-time, here's a work-around.

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