Joel Moss joelmoss

Faster Rails tests

Feedback loop speed in one of the biggest contributing factors to overall development time. The faster you get results, the faster you can move on to other things. A fast enough test suite is therefore critical to teams' success, and is worth investing some time at the beginning to save in the long run.

Below is a list of techniques for speeding up a Rails test suite. It is not comprehensive, but should definitely provide some quick wins. This list of techniques assumes you're using minitest, but most everything should translate over to rspec by simply replacing test/test_helper.rb with spec/spec_helper.rb.

Lead with data
bcrypt
bootsnap
Cache Time::utc calls

Generating SSL keys for development

Installation

Thanks to minica it is very easy to create trusted SSL certificates that have a very long expiration date.

In order to get started you have to have the go tools installed and set up correctly in your environment.

Setup

Proposal: Importable Constructable Stylesheets

We're getting Constructable Stylesheets. This seems like an intuitive value to obtain when importing CSS from JavaScript, since it's the DOM's representation of a Stylesheet:

import stylesheet from './style.css';
console.log(stylesheet);  // CSSStyleSheet

No such system is in place to allow this to work (see [whatwg/loader]), however frontend build tooling has congregated around this approach as a mechanism for bringing CSS assets into the JavaScript module graph. There are many benefits to be obtained from moving CSS into this graph, however the most important is that imported CSS can be attributed to the consuming JS Module. This allows it to be bundled, optimized, and potentially dead-code-eliminated leveraging static analysis performed on the surrounding module graph.

PLEASE NOTE: Do not publicly post your answers on this Gist, please forward them to your recruiting contact instead ;-)

1. Voting

Each voter can vote in zero or more referenda. Each referendum has one or more questions, and each question is a yes/no vote. Write the simplest normalized schema to describe this in generic SQL statements or as an entity-relationship diagram. Point out where the indexes would be if you want to quickly know the results of a given referendum question, but you never expect to query a single voter's voting record. In what way does the nature of the application affect your design judgment about privacy, and what effect would that have on normalization considerations?

2. Rewriting history with git

You've getting ready to submit a pull request to the coolapp repo. You branch contains two commits: M, followed by N. The lineage is this:

`constant-locals-loader` for Webpack

This loader optimizes the output of mini-css-extract-plugin and/or css-loader, entirely removing the potentially large CSS classname mappings normally inlined into your bundle when using CSS Modules.

Run npm install constant-locals-loader, then make these changes in your Webpack config:

module.exports = {
 module: {

	set :format, :capture


	# rest of your deploy.rb goes here


	after 'deploy:started', 'notify:flowdock:started' do
	$flowdock_deploy_thread = Deployer::Flowdock::Deployment.new(application: fetch(:application),
	environment: fetch(:rails_env) \|\| fetch(:rack_env),
	repo_name: fetch(:repo_url).gsub(/\[email protected]:(.*).git/, "\\1"),

	class NotificationsController < ApplicationController
	def notify_me

	# Rails reserve a db connection from connection pool for each request, lets put it back into connection pool.
	ActiveRecord::Base.clear_active_connections!

	# required header
	response.headers['Content-Type'] = 'text/event-stream'

	sse = ActionController::Live::SSE.new(response.stream)

	#!/usr/bin/env node

	/**
	* Git COMMIT-MSG hook for validating commit message
	* See https://docs.google.com/document/d/1rk04jEuGfk9kYzfqCuOlPTSJw3hEDZJTBN5E5f1SALo/edit
	*
	* Installation:
	* >> cd <repo>
	* >> ln -s ../../validate-commit-msg.js .git/hooks/commit-msg
	*/

	function ChatScroller(props) {
	const ref = useRef()
	const shouldScrollRef = useRef(true)
	useEffect(()=> {
	if (shouldScrollRef.current) {
	const node = ref.current
	node.scrollTop = node.scrollheight
	}
	})
	const handleScroll = () => {

	ruby_block 'remove_dynamically_oneshot' do
	block { node.run_list.remove('recipe[mycookbook::oneshot]') }
	end