RubyConf Snippets(RubyConf Australia 2014 - Feb 18-20)

What is it?● Annually in Australia (Melbourne/Sydney)● Around the world (e.g. Miami, India, Argentina)● Variety of talks held over 2 days ● Local and International speakers● A day of workshops (e.g. Rails Girls Next, C Extensions,

Rspec)● Best practises, examples, inspiration, meet new people● Videos - http://vimeo.com/rubyau

This Year● Continuous Delivery● Rails Engines● Middleware● Ruby 2.1● Minitest● Programming as a Parent● Asset Pipeline● MongoDB● Concurrency Practices in Ruby● JRuby● Security● Loads more ... https://m.lanyrd.com/2014/rubyconf-au/schedule/● Videos - http://vimeo.com/rubyau

The Snippets● Continuous Deployment● Rails Engines● C Extensions● Community

Continuous Deployment

Continuous Deployment

Rails Engines

Rails Engines● Slow● Buggy● New features take too

long● Disploys are

complicated● So many

dependencies

Rails Enginesrails plugin new <engine_name> --mountable

rails g controller <controller_name>

rake db:migrate

rake <engine_name>:install:migrations

gem 'engine_name', path: "vendor/engines/engine_name"

● engine.rb, routes.rb, application.rb● test app (test/dummy)● namespaced - routes, views, tables etc● migrations● SOA, Model Managers

Rails Engines● Avoid accessing ActiveRecord

directly● Domain API● Smart & Fast test suite => test

changes in the changed engine

C Extensions● C code in a Ruby Gem● E.g. nokogiri● Testable (write Rspec on C code!)● Why? speedier (Ruby is not slow, but not great on

processing e.g. image processing)● Ruby wrapper for C libs

C Extensionsbundle gem <gem_name> create the gem

# <gem_name>.gemspec

spec.add_development_dependency "rake-compiler"

# Rakefile

require "rake/extensiontask"

Rake::ExtensionTask.new('rbshop') do |ext|

ext.lib_dir = "lib/rbshop"

end

mkdir -p ext/gem_name C code lives here

C Extensions# ext/gem_name/extconf.rb add extension config file

require ‘mkmf’ creates makefile to compile C code

create_makefile(‘gem_name’)

# ext/gem_name/gem_name.c

initialise the extension

ruby.h is the C APIe.g. INT2NUM

C Extensions● free() and malloc()● Tell Ruby what

methods to allocate and free memory

● Ruby holds onto memory until it needs to free it

C Extensions➔ Call functions that define modules/classes:

◆ rb_define_module - Creates modules◆ rb_define_class_under - Creates a new class◆ rb_define_alloc_func - Lets you control how allocation happens

➔ Types◆ Strings, Arrays, Hashes, Numbers◆ Check_Type(r_radius, T_FLOAT)◆ E.g. Strings

● rb_str_new(const char *ptr, long len)● rb_str_new2(const char *ptr)● rb_str_cat(VALUE str, const char *ptr, long len)● rb_str_modify(VALUE str)

C Extensions

SPECSIn Ruby!!

Community● Rails Girls and Rails Girls Next● RoRo Syd● Ninefold, Re-Interactive● Installfest, Developer Hub● General Assembly● New Groups - Ruby Women, Women Who

Code

Questions ?