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//Javascript for finding latitude and longitude range boundaries.
//Based on the excellent Java example by http://janmatuschek.de/LatitudeLongitudeBoundingCoordinates

var GeoLocation = GeoLocation ? GeoLocation : {
  TO_RADIAN: 0.0174532925,
  TO_DEGREE: 57.2957795,
  EARTH_RADIUS: 6371.01,
  TO_MILE: 0.621371192,
  TO_KM: 1.609344,
  MIN_LAT: function() { return GeoLocation.degreeToRadian(-90) },

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#!/bin/bash
#
# Watch current directory (recursively) for file changes, and execute
# a command when a file or directory is created, modified or deleted.
#
# Written by: Senko Rasic <senko.rasic@dobarkod.hr>
#
# Requires Linux, bash and inotifywait (from inotify-tools package).
#
# To avoid executing the command multiple times when a sequence of

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* {
  background: #000 !important;
  color: #0f0 !important;
  outline: solid #f00 1px !important;
}

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NOTE: This is a question I found on StackOverflow which I’ve archived here, because the answer is so effing phenomenal.

---

Q: How can I make a chain of function decorators in Python?

---

If you are not into long explanations, see [Paolo Bergantino’s answer][2].

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Node.js Deployment

Steps to deploy a Node.js app to DigitalOcean using PM2, NGINX as a reverse proxy and an SSL from LetsEncrypt

1. Sign up for Digital Ocean

If you use the referal link below, you get $10 free (1 or 2 months) https://m.do.co/c/5424d440c63a

2. Create a droplet and log in via ssh

I will be using the root user, but would suggest creating a new user

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Never touch your local /etc/hosts file in OS X again

NOTE this has been done properly by a guy here: https://www.stevenrombauts.be/2018/01/use-dnsmasq-instead-of-etc-hosts/

You should go and do that now, ignore all of this.

To setup your computer to work with *.dev domains, e.g. project.dev, awesome.dev and so on, without having to add to your hosts file each time.

Requirements

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RESP3 specification

Versions history:

• 1.0, 2 May 2018, Initial draft to get community feedbacks.

Background

The Redis protocol has served us well in the past years, showing that, if carefully designed, a simple human readable protocol is not the bottleneck in the client server communication, and that the simplicity of the design is a major advantage in creating a healthy client libraries ecosystem.

Yet the Redis experience has shown that after about six years from its introduction (when it replaced the initial Redis protocol), the current RESP protocol could be improved, especially in order to make client implementations simpler and to support new features.

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Golden rules for System Design

👉 For a Read-Heavy System - Consider using a Cache.

👉 For a Write-Heavy System - Use Message Queues for async processing

👉 For a Low Latency Requirement - Consider using a Cache and CDN.

👉 If we need a system to be ACID complaint, we should go for RDBMS or SQL Database

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Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

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#!/usr/bin/env python

#
# Converts any integer into a base [BASE] number. I have chosen 62
# as it is meant to represent the integers using all the alphanumeric
# characters, [no special characters] = {0..9}, {A..Z}, {a..z}
#
# I plan on using this to shorten the representation of possibly long ids,
# a la url shortenters
#