subelsky

# I have a function that looks up a monthly report which may or may not exist yet (e.g. if 
# you look at the start of a month, before I've gotten around to generating that month's
# report)
#
# where the report isn't generated I just want to return "0" for each column in this report;
# so what I do is return an instance of the below object whenever there's no report 
# available (thus avoiding any "try" unpleasantness) - something about this slightly 
# bothers me though. Is there a more elegant/simpler way I should consider?
 
class NullZeroObject

subelsky

gem "rack-ssl", "1.3.2"

# when Capybara issue 409 or 422 get resolved, you can switch back to the official
# capybara gem
# https://github.com/jnicklas/capybara/pull/409
# https://github.com/jnicklas/capybara/pull/422

gem "capybara", git: "https://github.com/mcolyer/capybara.git", branch: "fix-ssl-redirects"

subelsky

namespace :audio do
  desc "downsample, segment, and upload audio files"
  task :load => :environment do
    access_key_id = ENV['AWS_ACCESS_KEY_ID']
    secret_access_key = ENV['AWS_ACCESS_KEY']
    source_dir = ENV['SOURCE_DIR']

    fail "Must specify AWS_ACCESS_KEY_ID, AWS_ACCESS_KEY, and SOURCE_DIR" if access_key_id.blank? || secret_access_key.blank? || source_dir.blank?
    filenames = Dir["#{source_dir}/**/**.*"]
    fail "#{source_dir} is empty" if filenames.empty?

subelsky

html = IO.read("survey.html")
rows = Nokogiri::HTML(html).css("tr")[????].collect { |r| r.children.to_a.values_at(0,3).collect(&:content) }.sort_by(&:last).reverse.collect { |r| "#{r.first} - #{r.last}" }

subelsky

# As soon as I create a Rails migration I always want to open that file in an editor. 
# I'd like to submit the following patch to Rails to create an --editor argument
# for the migration generator but I can't quite figure out the Thor way of doing this.

require 'rails/generators/active_record'

module ActiveRecord
  module Generators
    class MigrationGenerator < Base
      argument :editor, :type => :string, :lazy_default => ENV['EDITOR'], :required => false, :banner => "/path/to/your/editor", :desc => "Open migration using specified editor (defaults to EDITOR)"

subelsky

# Two of the projects we'll be discussing are heavily dependent on code like the example below, which
# requests stock price information from Google's finance API and transforms the results into a hash 
# for use in our database. This pattern shows up over and over in my projects. I always setup a separate 
# codebase containing a bunch of worker" modules that just do stuff like this.
#
# I need to write a bunch more of these for a variety of data sources. My plan is to start you off 
# on these, then graduate to more complex features.
#
# Here are two things for you to try:
#

subelsky

# I run this command once a week on all of my active projects
# It helps ensure that I'm always able to use the latest/greatest
# versions of various dependencies, or at least that I find out
# quickly when I've become locked into a particular version 
# (which just happened with the latest versions of the Ruby gems
# Webmock and VCR

alias mrupd='git pull && bundle update && rdbm && rspec spec; sd'

# the alias stands for 'massive rails update' because I have a bunch of other aliases that

subelsky

# BEGINNER: how to get started with ruby
# http://www.rubystudyhall.com/getting_started_with_ruby
# http://tryruby.org

# irb
# run "Hello, World" from command line
# do simple calculations
# read a file and count the lines in it
# read a file from command line argument

subelsky

# how to use https://github.com/subelsky/subelsky_power_tools/blob/master/lib/subelsky_power_tools/controller_shared_behavior.rb

describe PlatformsController do
  it_should_behave_like "a protected plural controller" do
    let(:user) { create(:user) }
    let(:object_not_owned_by_user) { create(:platform) }
    let(:valid_change_params) { { platform: { username: "HEYWOOD" } } }
    let(:user_sign_in_proc) { lambda { sign_in user } }
    let(:signin_redirect) { new_user_session_url(protocol: "http") }
    let(:not_found_redirect) { root_url }

subelsky

# Flatten a transparent image with a white background:
convert -flatten img1.png img1-white.png

# Make an image transparent
convert -transparent '#FFFFFF' nontransparent.gif transparent.png

# convert an image into tiles
convert -size 3200x3200 tile:single_tile.png final.png

# making a montage from a collection of images