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Nate Hopkins hopsoft

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hopsoft / db.rake
Last active Sep 17, 2020
Rails rake tasks for dump & restore of PostgreSQL databases
View db.rake
# lib/tasks/db.rake
namespace :db do
desc "Dumps the database to db/APP_NAME.dump"
task :dump => :environment do
cmd = nil
with_config do |app, host, db, user|
cmd = "pg_dump --host #{host} --username #{user} --verbose --clean --no-owner --no-acl --format=c #{db} > #{Rails.root}/db/#{app}.dump"
puts cmd
hopsoft / prefetch.js
Last active Sep 17, 2020
Turbolinks Prefetching
View prefetch.js
const hoverTime = 400
const fetchers = {}
const doc = document.implementation.createHTMLDocument('prefetch')
function fetchPage (url, success) {
const xhr = new XMLHttpRequest()'GET', url)
xhr.setRequestHeader('VND.PREFETCH', 'true')
xhr.setRequestHeader('Accept', 'text/html')
xhr.onreadystatechange = () => {
hopsoft / model_supports_bulk_updates.rb
Last active Sep 3, 2020
ActiveRecord Bulk / Batch Update
View model_supports_bulk_updates.rb
# frozen_string_literal: true
module ModelSupportsBulkUpdates
extend ActiveSupport::Concern
module ClassMethods
# Performs a bulk update with an efficient single query for all the records in the list.
# Note that the records are not reloaded form the database.
# This means that ActiveRecord will still see these records as dirty after the bulk_update.
def bulk_update(records)
hopsoft / example.html.erb
Created Aug 13, 2020
StimulusReflex + SlimSelect that supports DOM mutations and reentrancy triggered by reflexes
View example.html.erb
<%= :country_codes, country_select_data, {}, {multiple: true, data: {
controller: "select", action: "stimulus-reflex:after@document->select#delayedSetup", reflex: "change->Adapter#assign_attributes"}} %>
hopsoft /
Created May 21, 2019
Install ruby with rbenv and jemalloc on ubuntu
sudo apt-get update
sudo apt-get install libjemalloc-dev
RUBY_CONFIGURE_OPTS='--with-jemalloc' rbenv install 2.6.3
# test (look for jemalloc warnings)
MALLOC_CONF=invalid_flag:foo ruby -v
hopsoft / benchmarks.rb
Last active Jun 11, 2020
Ruby 2.3 safe navigation `&.` vs Active Support's try
View benchmarks.rb
require "benchmark"
require "active_support/all" do |x|
count = 1_000_000
label_size = 20 "check for nil:".rjust(label_size) do
count.times { nil && nil.length }
hopsoft / examples_reflex.rb
Last active May 17, 2020
Surgical DOM Updates with StimulusReflex
View examples_reflex.rb
# app/reflexes/examples_reflex.rb
class ExamplesReflex < ApplicationReflex
include CableReady::Broadcaster
before_reflex :surgical_update, only: [:noop]
def surgical_update
selector: "#example-container",
html: ExampleController.render(
hopsoft / action_controller_parameters.rb
Created Jan 19, 2018
Manually & Recursively Filter Rails Params
View action_controller_parameters.rb
module ActionControllerParameters
def filtered
filter_hash self.to_unsafe_hash
def filterer
@filterer ||=
hopsoft / example_job.rb
Last active Oct 25, 2019
Render views outside of the standard request context (i.e. ActiveJob) with Devise/Warden
View example_job.rb
class ExampleJob < ApplicationJob
queue_as :default
def perform(user)
# do some work
# HACK: get around limitations in devise/warden when rendering
# views outside the context of a formal http request
renderer =
renderer_env = renderer.instance_eval { @env }
hopsoft /
Last active Aug 8, 2019
Create and publish an NPM package cheat sheet
  1. Create an account on NPM

  2. Init your project

    mkdir example
    cd example
    yarn init
  3. Create a JavaScript file

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