I just released version 1.0.0 of symlink_fast. This is a plugin for Capistrano which simplifies post-deploy config symlinking by providing an interface for the task and doing it all in a single call to run. On larger application deployments with large numbers of configs that need to be symlinked, the time savings can be significant.

symlink_fast has been released as a gem on Rubygems.org. It can be installed either by typing:

gem install symlink_fast

or by adding the following to your Gemfile:

gem 'symlink_fast'

There is a Github page for the project:

https://github.com/spikegrobstein/symlink_fast

after a much too long hiatus, a new version of mcwrapper has been released. A new branch has been created for it: stable/1.5 as well as a new 1.5.0 tag.

This version of mcwrapper comes with quite a few additions, of which, the most important are the following:

• a plethora of exit codes for more robust scriptability (see source for complete list)
• install action for install wizard for minecraft_server.jar which will download and install the latest version
• upgrade action which gracefully stops the server, upgrades minecraft_server.jar and starts it back up again
• an about action for getting additional information about the project
• documentation for backup action
• restore action for restoring from previous backup
• prop action dumps entire properties file if no property is specified
• mcwrapper now monitors the server to ensure that it’s running. If it exits, mcwrapper will also exit (no more zombie mcwrapper processes)
• various optimizations and code cleanup

so I’m reading this article:

http://deviceguru.com/google-tv-vs-apple-tv-vs-boxee-vs-roku/

and I’m now 100% convinced that there is no decent media centre device. They’re all too locked down to do anything useful as you’re at the mercy of the manufacturer to resolve bugs and implement new features and support new media sources.

I think the best bet is to purchase/build a real PC and drop media centre software onto it (eg: XBMC, Boxee, Plex, whatever). With that, you can play any format and aren’t limited by features because even at a worst case, you can use VLC or a browser (Chrome, Firefox) to play video from an unsupported file format or site.

It’s just disappointing that computer manufacturers are beginning to drop support for media centre PCs lately. Dell had this awesome $250 machine (I think it was called the Zinio) which they discontinued. It was capable of playing 1080p video including flash video, had HDMI and good sound support (I forget the details of that). There was this other company that was shipping a smaller similarly priced and similarly spec’d machine with an even less expensive bare-bones model, but I can’t seem to find the info for that guy.

It should be possible to deliver a machine that’s powerful enough to do all the video stuff, along with running applications (eg: SickBeard) and web for < $400. The big win would be to have decent resource management so that when it’s playing video, it can guarantee resources to the video so it doesn’t skip while other background processes are running.

I’ve got my MacMini for my media centre and it’s ok, but it’s kinda expensive to use strictly as a HTPC and playback suffers when files are being copied while I’m watching high-bitrate videos.

Too bad no manufacturers are really targeting this market. They’re all concerned about racing to the bottom and delivering customized experiences. They should pick up an open source project and extend it and ship it on their device. There are plenty such projects out there and they’re quite mature.

Last night I released version 1.4.2 of mcwrapper. This fixes a major bug that cropped up recently involving the mechanism that reads commands from the FIFO. A nice Redditor fixed the bug, refactored my function and sent me a pull request last night and after a little QA, I merged his code and tagged the 1.4.2 release.

When I release 1.5 (towards the end of september), it will have an updater rolled up with it, so updating mcwrapper will be much more painless in the future.

As usual, you can either git pull if you cloned my repo or download the new version and manually update from one of the following locations:

• https://github.com/spikegrobstein/mcwrapper/zipball/1.4.2
• https://github.com/spikegrobstein/mcwrapper/tarball/1.4.2

and mcwrapper’s project page is located at:

• https://github.com/spikegrobstein/mcwrapper

I just released version 1.4 of my mcwrapper application. This update improves usability, and adds a couple new features. Overall, it’s a minor release.

Changes include:

• New log action. Will show server.log output in real-time.
• Added new BACKUP_ON_EXIT config option. When enabled, this will create a backup whenever you stop the Minecraft server.
• Added new scripts which can be double-clicked to start/stop the server and create backups. This makes it easier on commandline-impared users.

1.4 also includes an enhancement from 1.3.1 (a silent release) that fixes a bug where mcwrapper will slowly eat all the memory on your system as it reads commands from the FIFO. This was caused by using a recursive function when a simple loop would have been sufficient.

I’m aiming to get 1.5 released by the end of September which should include both launchd and ubuntu init scripts, backup restoration and other enhancements.

mcwrapper’s GitHub project page is located at the following address:

https://github.com/spikegrobstein/mcwrapper

You can download 1.4 using the following links:

• zip: https://github.com/spikegrobstein/mcwrapper/zipball/1.4
• tgz: https://github.com/spikegrobstein/mcwrapper/tarball/1.4

I updated mcwrapper to fix some bugs since my last post. mcwrapper now creates the pipe properly and allows for more configuration options.

I also added a new script called mcbackup which will allow you to back up your Minecraft world data while the server is running without any service interruption. The backup script creates a directory called ‘backup’ in the Minecraft server directory and copies your world data and configuration files (whitelists, banned-ips, server.properties, etc) into a datestamped directory inside the backup directory. By default, it keeps the previous 5 backups, but that can be changed by editing the mcbackup script.

Now, you can easily back up your Minecraft world data from a cron without needing to write your own script.

Version 1.1.0 of mcwrapper is available for download:

https://github.com/spikegrobstein/mcwrapper/tarball/1.1.0

See the README for details.

Update (2011-08-30)

mcwrapper 1.4 has been released. it includes a slew of new features including backups. See other posts for more info or look at the github page:

https://github.com/spikegrobstein/mcwrapper

I’ve been running a Minecraft server off my MacMini for the past month or so and, in doing as much work as I have and being the vigilant SysAdmin that I am, it was really starting to irk me that there was no way to do proper automated backups of the Minecraft server world data.

The solution for this was that I needed to wrap minecraft_server.jar in another script that could somehow take commands as input and pass them off to the minecraft server so I wouldn’t need to run the daemon in the foreground. I wound up doing just that.

mcwrapper is the answer: https://github.com/spikegrobstein/mcwrapper

It’s got the ability to start and stop the server, which are the beginnings to getting launchd (OSX) and sysV init scripts (Linux) to enable you to treat minecraft_server.jar as a standard daemon.

Because I’m using a FIFO to communicate with the Minecraft process, you can also pipe data to the FIFO to execute arbitrary commands and script your cheats or stop Minecraft from writing to the world files while a backup process is run and start it back up when completed, thereby doing a full, automated backup without stopping the server.

See the README file for a quickstart and other details.

The software is only an alpha release right now, since I only spent about 2 hours on it already, but I believe it should be usable. As of this writing, it’s possible to start multiple instances of the server, but mcwrapper does check to make sure the server is running before issuing any commands.

I’ve been doing a lot of dabbling with Javascript lately; primarily focusing on working with the canvas element. It’s some pretty sweet stuff and really reminds me of my early pixel manipulation tasks in C++ and REALbasic in the late 90s.

I had written a version of Conway’s Game of Life in C++ on my mac at the time (7600/132mhz) and was surprised at how fast it ran. I figured I could build something similar in JS using the canvas element and direct pixel manipulation using getImageData() and putImageData().

My initial tests ran ok in Chrome, but ran pretty terrible in Safari. I’m pretty much limited to a 200px x 200px world plane and I’m trying to come up with ways of speeding it up. I’ve done a bit of multithreaded programming in the past, but never really did much with it since I don’t typically write things that would benefit from it, but this seemed like a perfect situation, assuming that JS can simulate threads with the setTimeout() function and that these “threads” would run across my processors.

My method of multithreading was to create a function that iterates over a section of the world plane. Since the image data is a one-dimensional array of pixels, this is done by simply creating a function that processes a cycle on a specific slice of the pixel data. When each chunk finishes, it updates an array (thread_status) by appending a ‘true’ to the end. If thread_status.length is equal to the number of threads, then it draws the current graphic to the canvas using putImageData(), resets thread_status and starts the render() function over again.

I was quite surprised when these additions offered absolutely zero benefit. I suppose I’ll have to figure out better ways of iterating over the world plane for each cycle of life. I’m sure there are better ways of doing it than I’m doing and if I had access to a vector unit or some matrix math libraries, it might seriously speed things up, too.

single-threaded code can be found at:

• https://github.com/spikegrobstein/js_conway

multithreaded branch:

• https://github.com/spikegrobstein/js_conway/tree/multithread

demo:

• http://spike.cx/tests/js_conway/?threads=8

in the demo, you can change the number of threads by changing the threads GET variable in the URL.

Frequently, I have a need to create little bits of code to test functionality of new languages, libraries, functions, plugins or routines. Because of this, I have stuck a directory in my home on all my computers which contains all these bits of test code. Since I’ve begun turning these tests in to git repositories, I decided to slap together a little script for managing new projects.

The script is still a bit of a work in progress but it works really well and I’ve stuck it up on github.

Have a look, let me know if it’s useful for you, too.

https://github.com/spikegrobstein/poc_builder

I just made my first release of some code I was working on for the past couple days. It’s a Javascript library whose purpose is to simplify delegation of web requests by leveraging anchor URLs (the data in the trailing # of the URL).

The project has been released under the MIT license.

The advantage of this library is that you don’t need to use CSS selectors to locate your links and attach click actions. Rather, the library will handle any link whose href attribute that starts with a #.

There are 2 classes included in the library:

• RouterCore — base class that handles routing and automatic handling of links
• MappingRouter — a simple class that allows for semi-complex delegation of request handling.

See the project github page for additional information and documentation:

https://github.com/spikegrobstein/js_router