erikvullings

export type ICallback<T> = (data: T, envelope: IEnvelope<T>) => void;

/** Message enveloppe */
export interface IEnvelope<T> {
  /* Uses DEFAULT_CHANNEL if no channel is provided */
  channel?: string;
  /** Topic name */
  topic: string;
  /** Payload */
  data?: T;

erikvullings

/**
 * Create a GUID
 * @see https://stackoverflow.com/a/2117523/319711
 *
 * @returns RFC4122 version 4 compliant GUID
 */
export const uuid4 = () => {
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
    // tslint:disable-next-line:no-bitwise
    const r = (Math.random() * 16) | 0;

erikvullings

/**
 * Deep copy function for TypeScript.
 * @param T Generic type of target/copied value.
 * @param target Target value to be copied.
 * @see Source project, ts-deepcopy https://github.com/ykdr2017/ts-deepcopy
 * @see Code pen https://codepen.io/erikvullings/pen/ejyBYg
 */
export const deepCopy = <T>(target: T): T => {
  if (target === null) {
    return target;

erikvullings

/**
 * Deep copy function for TypeScript.
 * @param T Generic type of target/copied value.
 * @param target Target value to be copied.
 * @see Source project, ts-deepcopy https://github.com/ykdr2017/ts-deepcopy
 */
export const deepCopy = <T>(target: T): T => {
  if (target === null) {
    return target;
  }

erikvullings

/**
 * Create a GUID
 * @see https://stackoverflow.com/a/2117523/319711
 *
 * @returns RFC4122 version 4 compliant GUID
 */
export const uuid4 = () => {
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
    // tslint:disable-next-line:no-bitwise
    const r = (Math.random() * 16) | 0;

erikvullings

/**
 * Create a cached version of a function.
 *
 * @example cachedCalcArea = cachify(calcArea);
 * @param fn Function whose results you want to cache
 * @see TypeScript version of https://dev.to/kepta/javascript-underdogs-part-1---the-weakmap-4jih
 */
export const cachify = <T extends object, R>(fn: (arg: T) => R) => {
  const cache = new WeakMap(); // Use Map() when dealing with non-object arguments
  return (arg: T) => {

erikvullings

/**
 * Convert RD (Rijksdriehoek) coordinates to WGS84 and vice versa.
 * @see https://thomasv.nl/2014/03/rd-naar-gps/
 */
const projectionBetweenRdWgs84 = () => {
  const x0 = 155000;
  const y0 = 463000;
  const f0 = 52.15517440; // f => phi
  const l0 = 5.38720621;  // l => lambda

erikvullings

import fs from 'fs';
import path from 'path';

/**
 * Recursively walk a directory asynchronously and obtain all file names (with full path).
 *
 * @param dir Folder name you want to recursively process
 * @param done Callback function, returns all files with full path.
 * @param filter Optional filter to specify which files to include, 
 *   e.g. for json files: (f: string) => /.json$/.test(f)

erikvullings

---
version: '2'
services:
  zookeeper:
    image: confluentinc/cp-zookeeper
    hostname: zookeeper
    extra_hosts:
    - "moby:127.0.0.1"
    ports:
      - "2181:2181"

erikvullings

# Phoenix, by default, uses a Postgres database, so start one via docker
docker pull postgres
# Expose it on port 8432
docker run -p 8432:5432 --name hello-postgres -e POSTGRES_PASSWORD=postgres -d postgres

# Install Erlang, Elixir, and now Phoenix
mix archive.install https://github.com/phoenixframework/archives/raw/master/phx_new.ez
# Create a new Phoenix app
mix phx.new hello
# Edit config/dev.exs and update your hostname. Add a port (default is 5432, but I've mapped it to 8432)