staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

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This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

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jesster2k10

JWT Auth + Refresh Tokens in Rails

This is just some code I recently used in my development application in order to add token-based authentication for my api-only rails app. The api-client was to be consumed by a mobile application, so I needed an authentication solution that would keep the user logged in indefinetly and the only way to do this was either using refresh tokens or sliding sessions.

I also needed a way to both blacklist and whitelist tokens based on a unique identifier (jti)

Before trying it out DIY, I considered using:

wbotelhos

require 'sidekiq/api'

# 1. Clear retry set

Sidekiq::RetrySet.new.clear

# 2. Clear scheduled jobs 

Sidekiq::ScheduledSet.new.clear

dhh

ruby '2.7.1'

gem 'rails', github: 'rails/rails'
gem 'tzinfo-data', '>= 1.2016.7'  # Don't rely on OSX/Linux timezone data

# Action Text
gem 'actiontext', github: 'basecamp/actiontext', ref: 'okra'
gem 'okra', github: 'basecamp/okra'

# Drivers

mrispoli24

Setting up Heroku and Cloudflare (the right way)

The following outlines how to setup Heroku + Cloudflare with a full SSL certificate. What this means is that communication between the browser and the Cloudflare CDN is encrypted as well as communication between Cloudflare and Heroku’s origin server. Follow these steps exactly and the setup is a breeze.

Step 1: Set up domain names in Heroku

First you want to add the root domain and the www domain to heroku. You do this by clicking into your production application, then going to settings and then scrolling down to Domains and certificates.

Here you will add <your_domain>.com and www.<your_domain>.com. This will give you two CNAME records. They will look something like <your_domain>.com.herokudns.com and www.<your_domain>.com.herokudns.com.

Step 2: Add CNAME records to Cloudfare.

rafaelfranca

require 'active_support'

class Foo
  def foo
    "foo"
  end

  def bar
    ActiveSupport::Deprecation.warn("bar is deprecated")

owaiswiz

# Unnecessary indexes slows down writes and consumes additional storage and memory.

# Just paste this snippet in your Rails console (bundle exec rails c).
# And it will print all redundant indexes that are already covered by another index on the table:
#   Table `pages`:  index `site_idx` (site_id) already covered by `site_slug_idx`   (site_id,slug)
#   Table `optins`: index `list_idx` (list_id) already covered by `list_active_idx` (list_id,active)


ActiveRecord::Base.connection.tables.map do |table|
  indexes = ActiveRecord::Base.connection.indexes(table).select(&:valid).reject(&:where) 

jonathanmoore

Share Counts

I have always struggled with getting all the various share buttons from Facebook, Twitter, Google Plus, Pinterest, etc to align correctly and to not look like a tacky explosion of buttons. Seeing a number of sites rolling their own share buttons with counts, for example The Next Web I decided to look into the various APIs on how to simply return the share count.

If you want to roll up all of these into a single jQuery plugin check out Sharrre

Many of these API calls and methods are undocumented, so anticipate that they will change in the future. Also, if you are planning on rolling these out across a site I would recommend creating a simple endpoint that periodically caches results from all of the APIs so that you are not overloading the services will requests.

Twitter

dvliman

$: (Dollar Colon) is basically a shorthand version of $LOAD_PATH. $: contains an array of paths that your script will search through when using require.
$0 (Dollar Zero) contains the name of the ruby program being run. This is typically the script name.
$* (Dollar Splat) is basically shorthand for ARGV. $* contains the command line arguments that were passed to the script.
$? (Dollar Question Mark) returns the exit status of the last child process to finish.
$$ (Dollar Dollar) returns the process number of the program currently being ran.
$~ (Dollar Tilde) contains the MatchData from the previous successful pattern match.
$1, $2, $3, $4 etc represent the content of the previous successful pattern match.
$& (Dollar Ampersand) contains the matched string from the previous successful pattern match.
$+ (Dollar Plus) contains the last match from the previous successful pattern match.
$` (Dollar Backtick) contains the string before the actual matched string of the previous successful pattern match.

DmitryTsepelev

How to run examples

1. Run $ createdb uniq-db-test to create DB
2. Run example with Ruby (e.g., $ ruby 1_find_or_create_by_single_thread.rb)

Benchmark output

With many successful INSERTs

Warming up --------------------------------------