theorygeek

# frozen_string_literal: true
class AssociationLoader < GraphQL::Batch::Loader
  attr_reader :klass, :association

  def initialize(klass, association)
    raise ArgumentError, "association to load must be a symbol (got #{association.inspect})" unless association.is_a?(Symbol)
    raise ArgumentError, "cannot load associations for class #{klass.name}" unless klass < ActiveRecord::Base
    raise TypeError, "association #{association} does not exist on #{klass.name}" unless klass.reflect_on_association(association)

    @klass = klass

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.

iscott

Cheat Sheet: Simple Authentication in Rails 6 with has_secure_password

The goal of this cheatsheet is to make it easy to add hand-rolled authentication to any rails app in a series of layers.

First the simplest/core layers, then optional layers depending on which features/functionality you want.

Specs
AUTHOR	Ira Herman
LANGUAGE/STACK	Ruby on Rails Version 4, 5, or 6

invisiblefunnel

module SQLApprovals
  def verify_sql(name:, &block)
    # List to store executed queries
    queries = []

    # An event listener to record the normalized queries
    subscriber = ->(_name, _start, _finish, _id, payload) do
      # You'll likely need to filter unrelated queries,
      # this is left as an exercise to the reader
      queries << PgQuery.normalize(payload[:sql])

yossorion

What I Wish I'd Known About Equity Before Joining A Unicorn

Disclaimer: This piece is written anonymously. The names of a few particular companies are mentioned, but as common examples only.

This is a short write-up on things that I wish I'd known and considered before joining a private company (aka startup, aka unicorn in some cases). I'm not trying to make the case that you should never join a private company, but the power imbalance between founder and employee is extreme, and that potential candidates would

kirs

# Cleans up branches like:
# if Shopify.rails_next?
#   # Rails 5 login
# else 
#   # Rails 4 login
# end
module RuboCop
  module Cop
    module ShopifyRails
      class RailsNextUnless < Cop

wrburgess

Optimizing Rails Static Assets on Heroku Cedar

Serving Rails static assets is hard, especially on Heroku Cedar where Heroku forces Rails to serve static assets itself (which isn't particularly performant nor worth your dyno-dollar)---this is different than Heroku Bamboo which used Varnish and is no more. To make the best of the situation, I highly recomend:

1. Using the Heroku-Deflater gem which will selectively gzips assets (it gzips text-based files; and excludes images or binary files, which can actually be bigger when gzipped)

2. Configure your production environment to set cache-control headers and get out of denial about how static assets are being served on Heroku Cedar

3. Use AWS Cloudfront (or a CDN of your choosing) to serve the assets. Cloudfront is great because you can use the same Distribution

derencius

requirement: your db name must have the same name as your app. (it does not have  _development on the name)

save this script in a common folder outside your project.

pauljohanneskraft

Cached Properties

Complicated, time expensive computed properties can be cached using the following pattern.

var a = Cached(0) {
    (a: Int) -> Int in
    print("did calculate")
    return a + 100
}

dhh

# Channel
class CommentsChannel < ApplicationCable::Channel
  def self.broadcast_comment(comment)
    broadcast_to comment.message, comment: CommentsController.render(
      partial: 'comments/comment', locals: { comment: comment }
    )
  end

  def follow(data)
    stop_all_streams