branneman

Better local require() paths for Node.js

Problem

When the directory structure of your Node.js application (not library!) has some depth, you end up with a lot of annoying relative paths in your require calls like:

const Article = require('../../../../app/models/article');

Those suck for maintenance and they're ugly.

Possible solutions

branneman

/**
 * Globals
 */
var Carrousel = function(elem) { this.init() };
Carrousel.prototype = { init: function() {} };
new Carrousel();

/**
 * Namespacing
 *  - No globals (only the namespace variable itself is global)

branneman

British English cheatsheet

In-depth

https://en.wikipedia.org/wiki/Comparison_of_American_and_British_English
https://en.wikipedia.org/wiki/American_and_British_English_pronunciation_differences
https://en.wikipedia.org/wiki/American_and_British_English_grammatical_differences
https://en.wikipedia.org/wiki/American_and_British_English_spelling_differences
https://en.wikipedia.org/wiki/Lists_of_words_having_different_meanings_in_American_and_British_English

Pronunciation

branneman

// FP Lenses
const lens = get => set => ({ get, set });
const view = lens => obj => lens.get(obj);
const set = lens => val => obj => lens.set(val)(obj);
const over = lens => fn => obj => set(lens)(fn(view(lens)(obj)))(obj);
const lensProp = key => lens(prop(key))(assoc(key));

branneman

Primitive Types & Reference Types in JavaScript

An explanation of JavaScript's pass-by-value, which is unlike pass-by-reference from other languages.

Facts

• JavaScript has 2 kinds of variable types: primitive and reference.
• A fixed amount of memory is reserved after creation of every variable.
• When a variable is copied, it's in-memory value is copied.
• Passing a variable to a function via a call also creates a copy of that variable.

Primitive Types

branneman

'use strict';

const whitelist = {
    '/static/img/photo.jpg': '/static/img/photo.webp'
};

exports.handler = (event, context, callback) => {

    // Grab HTTP request and it's headers
    const request = event.Records[0].cf.request;

branneman

var asyncParallel = function(tasks, callback) {
  var results = [];
  var count = tasks.length;
  tasks.forEach(function(task, index) {
    task(function(err, data) {
      results[index] = data;
      if (err) {
        callback && callback(err);
        callback = null;
      }

branneman

var fs      = require('fs'),
    exec    = require('child_process').exec,
    express = require('express'),
    app     = express();

app.get('/static/img/*.svg.*.png', function(req, res) {
    var pngFile = 'src' + req.url,
        svgFile = pngFile.substring(0, pngFile.indexOf('.svg') + 4);
    if (!fs.existsSync(svgFile)) {
        return res.render('404', {

branneman

$(function() {
    var resizeEnd;
    $(window).on('resize', function() {
        clearTimeout(resizeEnd);
        resizeEnd = setTimeout(function() {
            $(window).trigger('resize-end');
        }, 100);
    });
});

branneman

/**
 * This function polls the component's props for Apollo to set `props.data.loading` to `false`
 * @example
 *   await waitDuringLoadingState(testRenderer, TodoContainer)
 * @see {@link https://reactjs.org/docs/test-renderer.html}
 * @param {TestRenderer} testRenderer
 * @param {React.Component} testComponent
 * @returns {Promise}
 */
export function waitDuringLoadingState(testRenderer, testComponent) {