gstark

Use tcpdump to monitor mysql

  # Capture the packets
  sudo tcpdump -i eth0 port 3306 -s 65535 -x -n -q -tttt > tcpdump.out

  # analyze all the requests from a given host
  pt-query-digest --type=tcpdump --filter '($event->{host} || $event->{ip} || "") =~ m/192.168.248.64/' tcpdump.out

gstark

Leaving this gist in the hopes that this helps someone some day.

I was using a docker image with Alpine linux. In this docker container I installed a specific version of node via several methods (nodenv, asdf, etc.) and each time I had to add the gcompat package so I could run glibc applications.

When I tried to install many npm packages such as yarn and corejs and others I would get the error:

Error: spawn sh ENOENT

I belive I finally realized that Error: spawn sh ENOENT is happening since npm is trying to launch sh and there is some incompatibility with a glibc app running with gcompat trying to launch a non-glibc app like sh

gstark

I'm trying to run the rails test suite but I keep getting this error:

$ bundle exec rake postgresql:build_databases
createdb: database creation failed: ERROR:  encoding UTF8 does not match locale en_US
DETAIL:  The chosen LC_CTYPE setting requires encoding LATIN1.
createdb: database creation failed: ERROR:  encoding UTF8 does not match locale en_US
DETAIL:  The chosen LC_CTYPE setting requires encoding LATIN1.

gstark

Semantic Versioning

Details: http://semver.org/, http://apr.apache.org/versioning.html

Versions are denoted using a standard triplet of integers: MAJOR.MINOR.PATCH. The basic intent is that MAJOR versions are incompatible, large-scale upgrades of the API. MINOR versions retain source and binary compatibility with older minor versions, and changes in the PATCH level are perfectly compatible, forwards and backwards.

Patch level changes could also be for correcting incorrect APIs. In this case, the previous patch release may be incompatible, but because of bugs.

Minor versions may introduce new features, but do not alter any of the previous API.

gstark

require 'irb/completion'
require 'irb/ext/save-history'

# Require awesome_print in our environment
begin
  require 'awesome_print'
rescue LoadError
end

# Keep an IRB history

gstark

def sum_groups(arr)
  loop do
    chunks = arr.chunk(&:even?).map(&:last)
    
    return arr.length if chunks.all? { |list| list.size == 1 }

    arr = chunks.map(&:sum)
  end
end

gstark

Weclome to the Iron Yard Intro to Rails Crash Course

First step is to install the correct version of the Ruby environment:

rvm install ruby-2.4.2

gstark

I've owned and used Beyond Compare for a long time and its my go-to tool whenever doing Windows work. I miss it so much I recently went to see if it would run under wine installed via Homebrew. Surprisingly it works quite well. I still won't let up on my yearly emails to Beyond Compare support to encourage a native verison.

brew install wine --use-gcc
<download the beyond compare installer exe>
wine ~/path/to/installer.exe
<install>
wine ~/.wine/drive_c/Program\ Files/Beyond\ Compare\ 3/BCompare.exe

Its a darn good diff tool with great directory compare support, lots of config options. Surprisingly on my Mac via WINE its pretty damn speedy (once X11 is already loaded...)

gstark

# Take the smallest case possible, a one wide grid
#
# .
#
# The number of ways of navigating this is 1 (do nothing)
#
# 1
#
# Extending this to a 2x2 grid still has the 0 case
#

gstark

class String
  def py_slice(start, step = 1)
    start.step(step < 0 ? 0 : self.length, step).map { |index| self[index] }
  end
end

input = ARGF.readlines

for i in Range.new(0,input.size).step(4)
  northLasers, conveyorBelt, southLasers = input[i,3]