Raul Souza Lima raulsouzalima

a simple git branching model (written in 2013)

This is a very simple git workflow. It (and variants) is in use by many people. I settled on it after using it very effectively at Athena. GitHub does something similar; Zach Holman mentioned it in this talk.

Update: Woah, thanks for all the attention. Didn't expect this simple rant to get popular.

belongs_to:

Assigning an object to a belongs_to association does not automatically save the object. It does not save the associated object either.

has_one:

When you assign an object to a has_one association, that object is automatically saved (in order to update its foreign key).
In addition, any object being replaced is also automatically saved, because its foreign key will change too
If either of these saves fails due to validation errors, then the assignment statement returns false and the assignment itself is cancelled.
If the parent object (the one declaring the has_one association) is unsaved (that is, new_record? returns true) then the child objects are not saved. They will automatically when the parent object is saved.

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

-E: will describe the underlaying queries of the \ commands (cool for learning!)
-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

Project Title

One Paragraph of project description goes here

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

Postgres Cheatsheet

This is a collection of the most common commands I run while administering Postgres databases. The variables shown between the open and closed tags, "<" and ">", should be replaced with a name you choose. Postgres has multiple shortcut functions, starting with a forward slash, "". Any SQL command that is not a shortcut, must end with a semicolon, ";". You can use the keyboard UP and DOWN keys to scroll the history of previous commands you've run.

Setup

installation, Ubuntu

http://www.postgresql.org/download/linux/ubuntu/ https://help.ubuntu.com/community/PostgreSQL

Common Options

-#, --progress-bar Make curl display a simple progress bar instead of the more informational standard meter.

-b, --cookie <name=data> Supply cookie with request. If no =, then specifies the cookie file to use (see -c).

-c, --cookie-jar <file name> File to save response cookies to.

Getting started with Elixir - Part 1

If you have been reading blog posts, hacker news threads, your favorite developers tweets or listening podcasts at this point I'm pretty sure you heard about Elixir programming language. The language was created by José Valim, a well known developer in the open-source world, you probably know him from the Ruby on Rails MVC framework or from the devise and simple_form ruby gems him and his co-workers from the Plataformatec have been working in the last years.

Elixir, a brief history

According the José Valim, the language was born 2011. He had the idea to build the new language due the lack of good tools to solve the concurrency problems in the ruby world. At that time, after spending time studying concurrency and distributed focused languages he found two languages that he likes Erlang and Clojure which runs in the JVM. He liked everything he saw in the Erlang language (Erlang VM) and he hated the things he didn't see, like polymorphism, metaprogramming and languag

	require "csv"
	require "date"

	puts CSV::HeaderConverters.keys.inspect # => [:downcase, :symbol]

	# Add new header converter
	CSV::HeaderConverters[:remap] = lambda do \|raw_value\|
	raw_value = raw_value.to_sym
	case raw_value
	when :country

	class MyJob < ActiveJob::Base
	queue_as :urgent

	rescue_from(NoResultsError) do
	retry_job wait: 5.minutes, queue: :default
	end

	def perform(*args)
	MyService.call(*args)
	end

	module AuthRequestHelper
	def http_auth_as(username, password, &block)
	@env = {} unless @env
	old_auth = @env['HTTP_AUTHORIZATION']
	@env['HTTP_AUTHORIZATION'] = ActionController::HttpAuthentication::Basic.encode_credentials(username, password)
	yield block
	@env['HTTP_AUTHORIZATION'] = old_auth
	end

	def auth_get(url, params={}, env={})