Tomas Ruzicka LeZuse

Optimistic Locking assumes that a database transaction conflict is very rare to happen. It uses a version number of the record to track the changes. It raise an error when other user tries to update the record while it is lock.

usage

Just add a lock_version column to the table you want to place the lock and Rails will automatically check this column before updating the record.

Pessimistic locking assumes that database transaction conflict is very likely to happen. It locks the record until the transaction is done. If the record is currently lock and the other user make a transaction, that second transaction will wait until the lock in first transaction is release.

usage

Notes

This code handles any JS runtime error during rendering React components. Without this handling, once an error occurs, whole component tree is damaged and can't be used at all. With this handling, nothing will be rendered in production environment (error span in dev env.) + in production the error is logged to Sentry (if you are not using it just delete related code)
This is basicaly a workaround for proposed feature in React core - described in Issue: facebook/react#2461
Works for all variants of Component creation - React.createClass, extending React.Component and also stateless functional components.
To get this work, just put this snippet into your entry js file. Then it will work in whole application.
Also supporting React Hot Reload!
If you find this useful, please retweet https://twitter.com/Aldredcz/status/744650159942995968 :)

Ideas

specify custom error renderer (global / per component, e.g. by implementing method renderOnError() in a comp

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

Compile with:

webpack --config vendor.webpack.config.js
webpack --config app.webpack.config.js

Use with the following index.html

Strictly Frameworks

Mobiledoc - github.com/bustle/mobiledoc-kit - framework to build editors with a standardized JSON structure
ShareDB - github.com/share/sharedb - framework to sync any JSON document using operational transforms, add real-time collaborative editing to anything else
Bangle.dev - github.com/bangle-io/bangle.dev - toolkit built for building editors, based on prosemirror

Abstracted Editors

These use separate document structures instead of HTML, some are more modular libraries than full editors

	var scripts = ['app.a700a9a3e91a84de5dc0.js']; // script for all users

	var newBrowser = (
	'fetch' in window &&
	'Promise' in window &&
	'assign' in Object &&
	'keys' in Object
	);

	if (!newBrowser) {

	# fbr - checkout git branch (including remote branches)
	fbr() {
	local branches branch
	branches=$(git branch --all \| grep -v HEAD) &&
	branch=$(echo "$branches" \|
	fzf-tmux -d $(( 2 + $(wc -l <<< "$branches") )) +m) &&
	git checkout $(echo "$branch" \| sed "s/.* //" \| sed "s#remotes/[^/]*/##")
	}

	# fco - checkout git branch/tag

	import cx from 'classnames';
	import styles from './button.css';

	const Button = ({children}) => (
	<button className={cx({[styles.button]: true})}>{children}</button>
	);

	// If we didn't define .button inside button.css then the above cx call
	// looks like cx({[undefined]: true}) which actually means the class name
	// "undefined" is set.

	export default function(file, api) {
	const j = api.jscodeshift;
	const { expression, statement, statements } = j.template;

	return j(file.source)
	.find(j.ClassProperty)
	.replaceWith(p => {
	p.node.end++;
	return p.node;
	})

	// https://gist.github.com/edoardocavazza/47246856759f2273e48b
	(function () {
	if (typeof Object.setPrototypeOf === 'undefined' && typeof Object.getOwnPropertyNames === 'function') {
	var _exclude = ['length', 'name', 'arguments', 'caller', 'prototype'];

	function bindFunction(ctx, fn) {
	return function() {
	return fn.apply(this, arguments);
	}
	}