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John Mitchell
Works at John Tells All
Attended University of Maryland Baltimore County
Lives in Venice, CA
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John Mitchell

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Ian Douglas's profile photoJohn Mitchell's profile photo
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thanks Ian!  Raw Selenium can be kind of rough, Splinter sounds easier -- thanks for the ref.

Internally we might be adding or switching to Robot Framework.  Our QA guy Rene -- not a programmer -- was able to get it installed and running real, business-valuable tests pretty easily. Check it out!
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DevOps in Southern California
If you're a networking/DevOps person in Southern California, here is a meetup I recommend: UUASC - on Meetup The UNIX Users Association of Southern California is mostly about DevOps and system administration.  The last talk I attended was on Google's Kubern...
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Testing Patterns
Testing code is hard. As a developer, I want to write cool code to solve interesting, real-world problems. I don't want to be "smart" and write "smart tests" that are inscrutable, rather than spending time on writing more (feature) code. Here an article tha...
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Docker/Nginx Tip: run standalone
Instead of using Docker to tweak your Nginx config, it's possible to run Nginx directly so it won't become a daemon and make your container exit.  To wit: nginx -g 'daemon off;'
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extra Docker networking goodies
I work a great deal with Docker, connecting webservers and databases together, hiding everything behind a caching proxy like Nginx.  Docker is a wonderful tool, providing isolation and semi-magical capabilities like hiding an entire "cluster" of machines be...
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tiny "Hello World" webserver
I'm writing a Nginx configuration that will wrap password protection on top of a bunch of dependent web servers. For testing, I want a few "hello world" type web servers, each of one gives a different message, but is really tiny. The following is what I cam...
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John Mitchell

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TIP: tweak number of Gunicorn workers
Count number of Gunicorn workers $ pgrep gunicorn.*work | wc -l 5 Add another worker by signaling the Gunicorn master $ sudo pkill -TTIN  gunicorn.*mast Verify another worker has appeared $ pgrep gunicorn.*work | wc -l 6 Decrease the number of workers, veri...
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it's unclear if "more workers" means cloning an old worker (old code), or loading a new worker from scratch (new code). If you find out let me know!

Our production server has Nginx and Gunicorn. I asked The Interwebs about how many workers for each one, and they said "2N+1", but that is for Nginx or Gunicorn alone, not necessarily together. Fortunately apachebench is working well for us, so given enough coffee all bugs are shallow. ;)

cheers Ian
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networking with the Ant-ernet
Harvester ants and the Internet protocol TCP both have the same goal: maximize transfer of bits/food in as efficient a manner as possible. It turns out they use the same protocol! http://priceonomics.com/the-independent-discovery-of-tcpip-by-ants/
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Except that harvester ants don't have to deal with buffer bloat.
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<3
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Docker/Fig tip: easily watch cluster logs
When using Fig to run a cluster of Docker containers, it's handy to have a console, and also a separate terminal with information so you can see what's going on.  That is, an interactive console, plus all the logs from all the containers. Use Fig to start y...
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OSX Docker Tip: set datetime
OSX doesn't directly support the awesomeness that is Docker containers. It uses an intermediate Linux virtual machine, and that runs containers for you, on your behalf. I started getting weird Amazon S3 errors. My project would work locally (in OSX), and wo...
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awful, but useful, Python
Have you ever wanted to open and decompress all log files, streaming each line to the caller? In Python, this is: import bz2, sys from itertools import chain # set 'lines' to all lines of all files after they've been decompressed lines = chain(*(bz2.BZ2File...
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People
In his circles
114 people
Have him in circles
123 people
Lars Lehtonen's profile photo
Amanda Johnstone-Batt's profile photo
Ian Douglas's profile photo
Robert Banz's profile photo
Nic Watson's profile photo
Dave Brookshire's profile photo
Graham Thompson's profile photo
Joshua Quattlebaum's profile photo
Thomas Liakos's profile photo
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Map of the places this user has livedMap of the places this user has livedMap of the places this user has lived
Currently
Venice, CA
Previously
Baltimore,MD - Dallas,TX - San Antonio,TX
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Occupation
Trainer and Consultant
Skills
Asynchronous programming, Django, Python, DevOps
Employment
  • John Tells All
    2014 - present
  • Enventum
    Senior Programmer, 2012 - 2013
  • SendGrid
    Senior Programmer, 4 - 2013
  • Enventum
    Chief Technical Officer, 2013 - 2014
Education
  • University of Maryland Baltimore County
    Computer Science
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Gender
Male