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Dealing with Nested Documents in MongoDB and Talend (aka Baking a Cake)

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Abstract: MongoDB is a very popular document database that gives you a huge amount of flexibility when it comes to storing data. On the other hand, the traditional relational model is far less flexible in how data is stored - you're limited to columns and rows. Sometimes you want to go from a flexible model like MongoDB to a relational one, that's what this post attempts to explain using  Talend / JaspersoftETL  (ETL tools). I do not want to get into the relational vs non-relational model argument in this post - it's only an example if you need to do this for some reason...I'm pro choice :) Scenario: We have a JSON document in MongoDB that looks like this: { "id" : "0001", "type" : "donut", "name" : "Cake", "ppu" : 0.55, "batters" : { "batter" : [ ...
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Batch convert Asterisk GSM WAV files to mp3

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I am working on a fun project at work to provide web based visual voice-mail for a ticketing system. I realized Flash audio players are not able to play WAV files so had to work around that. Since users are also using voicemail files in other ways I can't just change the output format from Asterisk. The type of file that I'm working with is identifed with file ms0012.WAV as: msg0012.WAV: RIFF (little-endian) data, WAVE audio, GSM 6.10, mono 8000 Hz First I'll say that I found this post http://www.thiscoolsite.com/?p=73 but like some of the commenters I couldn't get the script to work. The author assumes some other format than Asterisk spits out by default. Lame would complain that Unsupported data format: 0x0031 The Tools Sox: http://sox.sourceforge.net/ Lame: http://lame.sourceforge.net/ So here's what I do: Convert GSM encoded wav to Microsoft PCM sox msg0012.WAV -s msg0012.wav Convert the PCM wav to mp3: lame msg0012.wav msg0012.mp3 And here's a script to...
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Linux Software RAID Nagios Monitoring & Failure Simulation

It's always nice to monitor to make sure your technology is working properly, it's nicer knowing that when it fails it will alert you to what happened so sometimes you need to test the scenarios. This is just an overview using Debian Lenny of how to use the Linux mdadm tool to create, destroy and rebuild a software RAID 1 (mirror) device. Throughout the process you will see the effects of the Nagios check_linux_raid plugin from the Nagios Plugins project. First I installed the Nagios plugins and mdadm: >apt-get install mdadm nagios-plugins I used fdisk to create two partitions: /dev/sdc1 & /dev/sdc2 (of equal size, in this case 40 MB, I know, I'm generous.) I then used the following command to create a RAID 1 array with the two disks. I happened to call it md0: >mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sdc1 /dev/sdc2 Created an ext3 filesystem on my array: >mkfs.ext3 /dev/md0 Mounted the new file system in an arbitrary location: ...
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