Dec 21

Sunday Post (Can I pretend it’s still Friday?): Pycon 2015

Hey All,

I can’t believe it’s getting to the end of 2014. What an amazing year this has been!

I just found out that my coworker and I have had our poster submission accepted into Pycon 2015’s poster presentation session.

I’m really excited that I get to again showcase my work in front of the Python community.

I hope everyone has a really great holiday! I look forward to writing my last blog post of 2014 next Friday.

Enjoy!

-Shea

Dec 12

Friday Post: Time Drift Sucks

Hey All,

I’ve been plagued by a bug at work for the past 6 months. Every so often, my oAuth library would fail out of the blue, causing some of my apps to die. It never occurred in production, only in our development environments. If I made the oAuth token by hand, or used the console, it worked fine. If I waited a few minutes, it would authenticate, and everything worked. Totally random, no rhyme or reason.

It wasn’t until this week when I was trying to use a library and upload some test files to an AWS S3 bucket that I got an error. My request time signature was 19 minutes behind the Amazon server. AWS (and my oAuth lib) have a 15 minute time window. But why was this happening? My clock was synced using NTP. I went to check my app and it had also failed. Then it hit me. I hadn’t rebooted my machine in a week. Our dev environments use vagrant, which runs a small virtual machine that containerizes our software. The virtual machine has its own clock, which gets synced on reboot. Over the week, it’s clock slowly drifted just enough that my timestamps failed for Amazon, and then for oAuth. Every so often it will resync, but not fast enough.

In 2014, I thought Time Drift was a thing of past, a relic of dying CMOS batteries, but it still exists today. So if you are ever using vagrant to develop your applications, setup an NTP daemon on the virtual machine, or just vagrant halt / vagrant up every so often 🙂

Happy Friday!

Dec 10

Holiday Shopping Guide 2014

Hey All,

Figured I would post a list of items that I feel would be awesome purchases for anyone with an electronics itch to scratch!

Holiday 2014

Raspberry Pi Model B+ (B PLUS) 512MB Computer Board
Raspberry Pi Model A+ (256MB)
Mayflash PS2 PS3 PC USB Universal Arcade Fighting Stick
Qanba Q1 PS3 & PC Joystick (Fightstick)
X-Arcade Video Game Controller – X-Arcade Solo
AmazonBasics High-Speed HDMI Cable – 6.5 Feet (2 Meters) Supports Ethernet, 3D, and Audio Return
Motorola USB Wall Charger with Micro USB Data Cable – Bulk Packaging (Black)
RASPBERRY PIHUB
Tontec® 7 Inches Raspberry Pi LCD Display Screen TFT Monitor AT070TN90 with HDMI VGA Input Driver Board Controller
Teensy++ 2.0
Super Scratch Programming Adventure! (Covers Version 1.4): Learn to Program By Making Cool Games
SanDisk Ultra 32GB UHI-I/Class 10 Micro SDHC Memory Card Up to 48MB/s With Adapter- SDSDQUAN-032G-G4A [Newest Version]
Rii Mini Wireless Keyboard with Mouse Touchpad-Black
Edimax EW-7811Un 150Mbps 11n Wi-Fi USB Adapter, Nano Size Lets You Plug it and Forget it, Ideal for Raspberry Pi, Supports Windows, Mac OS, Linux
SanDisk 16GB SDHC Card Class 4 Secure Digital High Capacity – Bulk Packaging
FlexPi Raspberry Pi Case (Blank)

 

Dec 03

Encade Portable Raspberry Pi Gaming Console Kickstarter

Hey All,

Just wanted to post a cool Kickstarter that I’m backing.  The people at Nzen Mods are designing a really cool Raspberry Pi based project.

https://www.kickstarter.com/projects/2032055368/the-encade-a-portable-raspberry-pi-gaming-console

It’s a portable Raspberry Pi based gaming console.  They are so close to hitting their goal, and only have 22 hours left.

Enjoy!

-Shea