Juan Rodriguez juan-rod

Group array of JavaScript objects by keys

This fork of JamieMason's implementation changes the key parameter to be an array of keys instead of just a single key. This makes it possible to group by multiple properties instead of just one.

Implementation

const groupBy = keys => array =>
  array.reduce((objectsByKeyValue, obj) => {
    const value = keys.map(key => obj[key]).join('-');

This content moved here: https://exploringjs.com/impatient-js/ch_arrays.html#quickref-arrays

Authentication with an Express API and Postgres

Setting Up

Let's make sure our Express app has the required base modules:

# within root of API
npm install --save express pg knex bcrypt
npm install --save-dev nodemon

NOTE: This guide is ONLY for devs who don't want to edit their yarn.lock file by hand. If you don't care about that please carry on.

So you've pulled the latest master

git checkout master
git pull

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	return [null, data]
	}).catch(err => [err])
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	/* Look ma, no try/catch */
	async function usageExample(params) {

	class MyPromise {
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	}

	// Internal state. `$state` is the state of the promise, and `$chained` is
	// an array of the functions we need to call once this promise is settled.
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	this.$chained = [];

	{
	"window.zoomLevel": -1,
	"editor.fontFamily": "Operator Mono, Menlo, Monaco, 'Courier New', monospace",
	"editor.fontSize": 29,
	"editor.lineHeight": 40,
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	"workbench.editor.tabSizing": "shrink",
	"eslint.autoFixOnSave": true,
	"eslint.alwaysShowStatus": true,
	"html.format.enable": true,

	#!/usr/bin/env bash

	# Brew
	echo "Installing 🍺 Brew!"
	/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
	echo "eval $(/opt/homebrew/bin/brew shellenv)" >> ~/.zshrc


	# Disable brew analytics
	brew analytics off

	// 🔥 Node 7.6 has async/await! Here is a quick run down on how async/await works

	const axios = require('axios'); // promised based requests - like fetch()

	function getCoffee() {
	return new Promise(resolve => {
	setTimeout(() => resolve('☕'), 2000); // it takes 2 seconds to make coffee
	});
	}

	$g: transparent;
	$steps: 10;
	@for $i from 1 to $steps {
	$g: append($g, fade-out($bg-color, 1 / $i) percentage($i / $steps), comma);
	$g: append($g, fade-out($bg-color, 1 / $i) percentage(($i + 0.6) / $steps), comma);
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	$g: append($g, $bg-color);
	background: linear-gradient(to bottom, $g);