mariochavez

The Task

Convert an entire folder of RAW images, typically produced by DSLR camera at 300dpi and convert them all to web-ready, 72dpi JPEG's in a single bash command while utilizing all eight threads in parallel on a quad-core i5 CPU.

OS X Prerequesites

Install ImageMagick with RAW support via Homebrew.

If you don't already have Homebrew, shame on you. Grab it like so:

mariochavez

Testing front-end for a Sinatra app with RSpec and Capybara

I've used Cucumber quite a bit on my last job. It's an excellent tool, and I believe readable tests are the way to the future. But I could never get around to write effective scenarios, or maintain the boatload of text that the suite becomes once you get to a point where you have decent coverage. On top of that, it didn't seem to take much for the suite to become really slow as tests were added.

A while ago I've seen a gist by Lachie Cox where he shows how to use RSpec and Capybara to do front-end tests. That sounded perfect for me. I love RSpec, I can write my own matchers when I need them with little code, and it reads damn nicely.

So for my Rails Rumble 2010 project, as usual, I rolled a Sinatra app and figured I should give the idea a shot. Below are my findings.

Gemfile

mariochavez

defmodule MyApp do
  use Application

  def start(_type, _args) do
    import Supervisor.Spec, warn: false

    children = [
      Plug.Adapters.Cowboy.child_spec(:http, MyApp.Router, [], [
        dispatch: dispatch
      ])

mariochavez

class ActiveRecord::Base
  mattr_accessor :shared_connection
  @@shared_connection = nil

  def self.connection
    @@shared_connection || ConnectionPool::Wrapper.new(:size => 1) { retrieve_connection }
  end
end
ActiveRecord::Base.shared_connection = ActiveRecord::Base.connection

mariochavez

These are the scripts that I used to migrate from RSpec to Minitest in a Rails aplication.

It is expected for the test suite to be in RSpec 3.x sintax.

1. Install rename library from Homebrew
2. Remove RSpec/TestUnit from Gemfile
3. Add minitest-rails gem
4. Rename spec forder to test
5. Add a test_helper.rb file

mariochavez

Esta semana dí una plática para WDT Colima sobre PostgreSQL

Aquí les dejo algunos recursos útiles:

1. https://www.postgresql.org
2. http://postgresapp.com La forma más fácil de instalara PostgreSQL en macOS
3. https://eggerapps.at/postico/ cliente de PostgreSQL para macOS
4. http://www.postgresguide.com
5. https://pgexercises.com
6. https://www.pgcasts.com

mariochavez

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

mariochavez

Resources for Machine Learning in Ruby

Gems

• liblinear-ruby: Ruby interface to LIBLINEAR using SWIG

• classifier-reborn: Bayesian and LSI classification
  dependencies: GSL

mariochavez

To circle.yml:

dependencies:
  post:
    - bin/cisetup

checkout:
  post:
    - git fetch origin --depth=1000000

mariochavez

In Rails 3

NOTE: This post now lives (and kept up to date) on my blog: http://hakunin.com/rails3-load-paths

If you add a dir directly under app/

Do nothing. All files in this dir are eager loaded in production and lazy loaded in development by default.

If you add a dir under app/something/