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Get the first commit of 2012

$ git log --pretty=format:'%H' --after="2011-12-31" | tail -1
d41d8cd98f00b204e9800998ecf8427e

Count the number of commits since then (inclusive)

$ git rev-list d41d8cd98f00b204e9800998ecf8427e^..HEAD | wc -l 
44555

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When using Git, I find myself doing a lot of what I call "exploratory merging" into a throwaway local branch. This is to preview what a scary merge might look like master, or to isolate a bug in a staging environment by selectively merging in certain of the branches that have been deployed.

The names of my throwaway branches always start with an underscore, so I can easily see them when I git branch. Below is a Bash one-liner (aliased as git purge) that deletes unmerged branches whose names start with "_".

[alias]
  purge   = !git branch --no-merged | tr -d "* " | grep ^_ | xargs git branch -D

whylom

Here are some quick notes on installing Graphite on a Vagrant virtual machine using Chef recipes from GitHub. This more or less assumes you know what you're doing with Vagrant and Chef.

Notes

• I used the "lucid32" Ubuntu base box you see in most Vagrant examples (http://files.vagrantup.com/lucid32.box)
• Where possible, I used the cookbooks from Opscode. I was forced to use alternatives for Python (did not work for me) and for Graphite (no Opscode cookbook as of now).
• The Graphite recipe depends on the Python, Apache2, and runit recipes.
• I'm running the apt recipe first to update the Ubuntu package manager. The out-of-date manager that ships with the lucid32 box errored out for me when running the Python recipe.

Cookbooks Used

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$ leggo 3306

Port 3306 is being used by "mysqld"

  process 66117 | started 4:53PM | up for 0:01.25

  /usr/local/Cellar/mysql/5.5.20/bin/mysqld
  --basedir=/usr/local/Cellar/mysql/5.5.20
  --datadir=/usr/local/var/mysql 
  --plugin-dir=/usr/local/Cellar/mysql/5.5.20/lib/plugin

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# Shell out to the fast and reliable `wc` utility.
def lines(path)
  # output of wc (returned by backticks) is formatted like this:
  # "     111 filename.ext"
  `wc -l #{path}`.strip.split(' ').first.to_i
end

# **/* gets all files and directories in all subdirectories.
files = Dir["/path/to/directory/**/*"]

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# First, some variables!
a, b = %w(foo bar)

# Good old-fashioned string interpolation.
"#{a} is not #{b}" #=> "foo is not bar"

# Today, I learned that this craziness works!
"%s is not %s" % [a, b] #=> "foo is not bar"

whylom

For security reasons, many hosting providers restrict external access to the default MySQL port 3306. But if you have SSH access to the database server, you can access the MySQL server from your local machine by using an SSH tunnel. An SSH tunnel forwards bits back & forth between a port on your machine and a port on the remote machine, all lovingly encrypted with SSH.

Here's how you do it! But first, my assumptions:

1. You already have configured SSH access to the remote server.
2. You want to access port 3306 on the remote server.
3. You want to access port 3307 on your local machine. This is simply because many devs (myself included) routinely have MySQL running on port 3307.

Here is the Unix command to open an SSH tunnel to hostname_or_ip with the user account username

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mysqldump --no-data -u root -ppw funky_database > funky_database.sql

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var blinking;

function startBlinking() {
  blinking = setInterval(function() {
    $('.light').toggleClass('on');
  }, 750);    
}

function stopBlinking() {
  clearInterval(blinking);

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words = ["Life", "Liberty", "and", "the", "pursuit", "of", "Happiness"]

words.grep(/^[A-Z]/) 
#=> ["Life", "Liberty", "Happiness"]

words.grep(/^([A-Z])/) { $1 } 
#=> ["L", "L", "H"]