jvns

You are trying to make a lot of simulataneous network connections to localhost. You get up to about 2000 HTTP requests per second, when your CPU usage goes up to 100% on all cores.

perf top reports the following:

 31.01%  [kernel]                    [k] inet_csk_bind_conflict
 20.60%  [kernel]                    [k] inet_csk_get_port
  9.82%  [kernel]                    [k] _raw_spin_lock
  4.62%  perf                        [.] 0x0000000000038ba1
 3.90% [kernel] [k] _raw_read_unlock_bh

Bomadeno

class Api::RegistrationsController < Api::BaseController
  
  respond_to :json
  def create

    user = User.new(params[:user])
    if user.save
      render :json=> user.as_json(:auth_token=>user.authentication_token, :email=>user.email), :status=>201
      return
    else

henrik

# Without this fix, downgrading from Rails 4 to Rails 3 causes session cookies to blow up.
#
# The way the flash is stored in the session changed in a backwards-incompatible way.

if Rails::VERSION::MAJOR == 3

  module ActionDispatch
    class Flash
      def call(env)
        if (session = env['rack.session']) && (flash = session['flash'])

peter

class ImportLegacyDevices < ActiveRecord::Migration
  def self.up
    return unless Rails.env.production?

    legacy_devices.each do |device_id, issue|
      if device = Device.find_by_hardware_id(device_id)
        unless InclusiveIssue.exists?(:issue_id => issue.id, :device_id => device.id)
          InclusiveIssue.create!(
            :issue => issue,
            :device => device,

myronmarston

its isn't core to RSpec. One the of the focuses of RSpec is on the documentation aspects of tests. Unfortunately, its often leads to documentation output that is essentially lies. Consider this spec:

User = Struct.new(:name, :email)

describe User do
  subject { User.new("bob") }
  its(:name) { should == "bob" }
end

demisx

cd my_rails_app_root_dir
rm bin/*
bundle exec rake rails:update:bin
bundle binstubs rspec-core
spring binstub --all

denmarkin

Then(/^I should see (.+) table$/) do |table_id, expected_table|
  html_table = table_at("##{table_id.parameterize.tableize}").to_a
  html_table.map! { |r| r.map! { |c| c.gsub(/<.+?>/, '').gsub(/[\n\t\r]/, '') } }
  expected_table.diff!(html_table)
end

chad

# How to find out where a method comes from.
# Learned this from Dave Thomas while teaching Advanced Ruby Studio
# Makes the case for separating method definitions into
# modules, especially when enhancing built-in classes.
module Perpetrator
  def crime
  end
end

class Fixnum

djspiewak

Introduction to scalaz-stream

Every application ever written can be viewed as some sort of transformation on data. Data can come from different sources, such as a network or a file or user input or the Large Hadron Collider. It can come from many sources all at once to be merged and aggregated in interesting ways, and it can be produced into many different output sinks, such as a network or files or graphical user interfaces. You might produce your output all at once, as a big data dump at the end of the world (right before your program shuts down), or you might produce it more incrementally. Every application fits into this model.

The scalaz-stream project is an attempt to make it easy to construct, test and scale programs that fit within this model (which is to say, everything). It does this by providing an abstraction around a "stream" of data, which is really just this notion of some number of data being sequentially pulled out of some unspecified data source. On top of this abstraction, sca

jbgo

This is how I debug SystemStackError when there is no stack trace.

My first attempt was:

begin
  a_method_that_causes_infinite_recursion_in_a_not_obvious_way
rescue SystemStackError
  puts caller
end