ProGM

Arel Cheatsheet on Steroids

A (more) complete cheatsheet for Arel, including NamedFunction functions, raw SQL and window functions.

Tables

posts = Arel::Table.new(:posts)
posts = Post.arel_table # ActiveRecord

Table alias

thetrevorharmon

// See tth.im/s3json for a full explanation of this code

const AWS = require('aws-sdk');
const S3 = new AWS.S3();

exports.handler = async (_, context) => {
  try {
    const query = 'SELECT * FROM s3object[*].results[*] r;';
    
    // test query is against data from https://swapi.co/api/planets/?page=2

bzerangue

NDJSON is a convenient format for storing or streaming structured data that may be processed one record at a time.

• Each line is a valid JSON value
• Line separator is ‘\n’

1. Convert JSON to NDJSON?

cat test.json | jq -c '.[]' > testNDJSON.json

guitmz

1. Run list-buckets command (OSX/Linux/UNIX) to list all S3 buckets available in your AWS account:

aws s3api list-buckets
  --query 'Buckets[*].Name'

2. The command output should return the name of each S3 bucket available in your AWS account:

jasonnoble

#!/usr/bin/env ruby
#
# Prerequisites:
#   gem install bundler
#   bundle install

dependencies = `bundle show | grep '*' | awk '{print $2, $3}' | sed -e 's/(//' -e 's/)//'`.split("\n")

dependencies.each do |dependency|
  (gem_name, version) = dependency.split

knee-cola

/**
 * @author knee-cola / https://github.com/knee-cola
 * Original file URL: https://gist.github.com/knee-cola/37875bc4359609b96c9f329cd2a68fa1
 */

// This is a simple progressive image loader for Three.js
// It enables the smaller image files to be loaded first,
// before the big texture image is fully loaded.
//
// The images are loaded in the order they are passed

askilondz

Adaptive Streaming has become the neccessity for streaming video and audio. Unfortantely, as of this post, there isn't a whole lot of tutorials that accumulate all of the steps to get this working. Hopefully this post achieves that. This post focuses on using Amazon Web Services (AWS) to transcode for HLS and DASH and be the Content Delivery Network (CDN) that delivers the stream to your web page. We'll be using Video.js for the HTML5 player as well as javascript support libaries to make Video.js work with HLS and DASH.

So Here's what you need:

• An AWS Account
• Video.js
• videojs-contrib-hls.min.js
• dash.all.min.js
• videojs-dash.min.js

Set up three S3 buckets

rondy

FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.

---

Effective Engineer - Notes

• By Edmond Lau
• Highly Recommended 👍
• http://www.theeffectiveengineer.com/

What's an Effective Engineer?

fernandoaleman

brew tap homebrew/versions
brew install v8-315

gem install libv8 -v '3.16.14.13' -- --with-system-v8
gem install therubyracer -- --with-v8-dir=/usr/local/opt/v8-315

bundle install

hfreire

# Install QEMU OSX port with ARM support
sudo port install qemu +target_arm
export QEMU=$(which qemu-system-arm)

# Dowload kernel and export location
curl -OL \
https://github.com/dhruvvyas90/qemu-rpi-kernel/blob/master/kernel-qemu-4.1.7-jessie
export RPI_KERNEL=./kernel-qemu-4.1.7-jessie

# Download filesystem and export location