dhh

# CLI
sudo apt update -y
sudo apt install -y \
	git curl docker.io \
	build-essential pkg-config autoconf bison rustc cargo clang \
	libssl-dev libreadline-dev zlib1g-dev libyaml-dev libreadline-dev libncurses5-dev libffi-dev libgdbm-dev libjemalloc2 \
	libvips imagemagick libmagickwand-dev \
	redis-tools sqlite3 libsqlite3-0 libmysqlclient-dev \
	rbenv apache2-utils

ptarjan

Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

baweaver

def has_pair_with_sum_brute_force(input, sum)
  # Boolean coercion. Just returning an int (index where found) can be confusing
  !!input.find.with_index do |value, i|
    # All we need to do is keep the inner loop one ahead of the outer.
    input[(i + 1)..-1].find do |sub_value|
      value + sub_value == sum
    end
  end
end

adactio

// Licensed under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
// http://creativecommons.org/publicdomain/zero/1.0/
(function (win, doc) {
    'use strict';
    if (!win.XMLHttpRequest || !win.FormData || !win.addEventListener || !doc.querySelectorAll) {
        // doesn't cut the mustard.
        return;
    }
    function hijaxForm (formElement) {
        var progressBar;

craigbeck

  query IntrospectionQuery {
    __schema {
      queryType { name }
      mutationType { name }
      subscriptionType { name }
      types {
        ...FullType
      }
      directives {

pixeltrix

When should you use DateTime and when should you use Time?

It's a common misconception that [William Shakespeare][1] and [Miguel de Cervantes][2] died on the same day in history - so much so that UNESCO named April 23 as [World Book Day because of this fact][3]. However because England hadn't yet adopted [Gregorian Calendar Reform][4] (and wouldn't until [1752][5]) their deaths are actually 10 days apart. Since Ruby's Time class implements a [proleptic Gregorian calendar][6] and has no concept of calendar reform then there's no way to express this. This is where DateTime steps in:

>> shakespeare = DateTime.iso8601('1616-04-23', Date::ENGLAND)
=> Tue, 23 Apr 1616 00:00:00 +0000
>> cervantes = DateTime.iso8601('1616-04-23', Date::ITALY)
=> Sat, 23 Apr 1616 00:00:00 +0000

FUT

1. Install Linux updates, set time zones, followed by GCC and Make

sudo yum -y update
sudo ln -sf /usr/share/zoneinfo/America/Indianapolis \
/etc/localtime
sudo yum -y install gcc make
 

2. Download, Untar and Make Redis 2.8 (check here http://redis.io/download)

pstaender

#!/usr/bin/ruby
 
require 'net/http'
require 'net/smtp'
 
# Brian Wigginton
# http://www.bwigg.com/2008/10/ruby-script-to-check-site-availability/
# 10/7/2008
#
# Check's availabilty of a website. Needs to be run via a cron job.

schneems

A not politically correct assertion of my feelings towards a piece of software:

Note: Repetition builds cynicism, asset_sync isn't bad, but when an asset problem cannot be solved via support it gets escalated to me. Often times someone using asset_sync the problem is due to their use of the library and not from Heroku.

Backstory

The asset sync gem uploads your assets (images, css, javascript) to S3. From there you can either point browsers to the copy on S3 or use a CDN + the S3 bucket. It's a good idea, and solved a problem at one time.

It is no longer needed and you should now use https://devcenter.heroku.com/articles/using-amazon-cloudfront-cdn instead. So rather than copying your assets over to S3 after they are precompiled the CDN grabs them from your website instead. Here's some reasons why it's better.

dkubb

require 'coercible'

class Transformer
  include Enumerable

  COERCER = Coercible::Coercer.new

  COERCIONS = Hash.new(:to_string).update(
    id:         :to_integer,
    updated_on: :to_date,