Milad Khajavi khajavi

Rough Notes about CQRS and ES

Once upon a time…

I once took notes (almost sentence by sentence with not much editing) about the architectural design concepts - Command and Query Responsibility Segregation (CQRS) and Event Sourcing (ES) - from a presentation of Greg Young and published it as a gist (with the times when a given sentence was heard).

I then found other summaries of the talk and the gist has since been growing up. See the revisions to know the changes and where they came from (aka the sources).

It seems inevitable to throw Domain Driven Design (DDD) in to the mix.

Spark SQL samples for Spark Meetup

Initialize

Docker

https://github.com/ueshin/docker

$ docker run -it -p 14040:4040 spark:1.1.0-rc4

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

JDK 8 Released

Most of us won’t be able to use/deploy JDK 8 in production for a looong time. But that shouldn’t stop us from using it, right?

It should be possible to sneak in JDK 8 in the back way, the same way we snuck in Groovy and other libraries we wanted to use.

The Test Suite to the rescue

The Maven compiler plugin run in two separate lifecycles, compile and testCompile. Those can be configured separately.

Patterns of Enterprise Application Architecture

By Martin Fowler (2002)

Chapter 1: Layering

A basic example of layering: FTP < TCP < IP < Ethernet

Benefis of layering:

You can understand a layer without knowing much about the others.
Minimize dependencies.

	import org.apache.spark._
	import org.apache.spark.graphx._

	val triplets = sc.textFile(path).flatMap { line =>
	if (!line.isEmpty && line(0) != '#') {
	val lineArray = line.split("\\s+")
	if (lineArray.length < 2) {
	None
	} else {
	val t = new EdgeTriplet[String, String]

	# Usage:
	# ruby -e "$(curl <url_to_this_raw_gist>)" https://www.youtube.com/watch?v=Jo1tjBmwuXI

	youtube_url = ARGV[0]

	puts "YouTube URL: #{youtube_url}"

	`mkdir youtube`
	Dir.chdir "youtube"
	`curl https://yt-dl.org/downloads/2014.10.13/youtube-dl > youtube-dl`

	var casper = require('casper').create({
	verbose: true,
	logLevel: 'error',
	pageSettings: {
	loadImages: false,
	loadPlugins: false,
	userAgent: 'Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.2 Safari/537.36'
	}
	});

	override def runJob(sc: SparkContext, config: Config): Any = {
	val fileName = config.getString("input.file")
	logger.info("### fileName : " + fileName)
	var rdd = this.namedRdds.get[String](fileName)
	logger.info("### rdd load 1 : " + rdd)
	if (rdd.isDefined) {
	logger.info("### rdd %s isDefined".format(fileName))
	}
	else {
	logger.info("### rdd %s doesn't exist... loading".format(fileName))

	git branch -m old_branch new_branch # Rename branch locally
	git push origin :old_branch # Delete the old branch
	git push --set-upstream origin new_branch # Push the new branch, set local branch to track the new remote