Jeff M lovejavaee

Introduction to Kafka

Kafka acts as a kind of write-ahead log (WAL) that records messages to a persistent store (disk) and allows subscribers to read and apply these changes to their own stores in a system appropriate time-frame.

Terminology:

Producers send messages to brokers
Consumers read messages from brokers
Messages are sent to a topic

How to connect an iOS device to your computer via a SOCKS proxy

Say you're running a virtual machine on your work computer. Say this machine, for whatever reason, can only connect to the internet over NAT - as in, it does not get it's own IP address. Say this VM is running a webserver, and you need a device outside of your computer to connect to it.

If only there was a way to get your work computer to 'share' it's network, so that you could get at that VM… Here's how you do it!

For all instructions, I assume your work computer is a mac

Get your computer's IP address:

Vagrant Setup

This tutorial guides you through creating your first Vagrant project.

We start with a generic Ubuntu VM, and use the Chef provisioning tool to:

install packages for vim, git
create user accounts, as specified in included JSON config files
install specified user dotfiles (.bashrc, .vimrc, etc) from a git repository

Afterwards, we'll see how easy it is to package our newly provisioned VM

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

	$ mvn verify
	[INFO] Scanning for projects...
	[INFO]
	[INFO] ------------------------------------------------------------------------
	[INFO] Building maven-tests-config 1.0-SNAPSHOT
	[INFO] ------------------------------------------------------------------------
	[INFO]
	[INFO] --- maven-resources-plugin:2.5:resources (default-resources) @ maven-tests-config ---
	[debug] execute contextualize
	[INFO] Using 'UTF-8' encoding to copy filtered resources.

	##
	# Creates an alias called "git hist" that outputs a nicely formatted git log.
	# Usage is just like "git log"
	# Examples:
	# git hist
	# git hist -5
	# git hist <branch_name>
	# git hist <tag_name> -10
	##
	git config --global alias.hist "log --pretty=format:'%C(yellow)[%ad]%C(reset) %C(green)[%h]%C(reset) \| %C(red)%s %C(bold red){{%an}}%C(reset) %C(blue)%d%C(reset)' --graph --date=short"

	@ControllerAdvice
	public class CustomResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {

	@Override
	protected ResponseEntity<Object> handleMethodArgumentNotValid(MethodArgumentNotValidException ex, HttpHeaders headers, HttpStatus status, WebRequest request) {
	List<FieldError> fieldErrors = ex.getBindingResult().getFieldErrors();
	List<ObjectError> globalErrors = ex.getBindingResult().getGlobalErrors();
	List<String> errors = new ArrayList<>(fieldErrors.size() + globalErrors.size());
	String error;
	for (FieldError fieldError : fieldErrors) {

	package testng.samples;

	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.Random;

	import org.testng.ITestContext;
	import org.testng.TestNG;

	package org.bk.samples.cache;

	import static org.hamcrest.MatcherAssert.assertThat;
	import static org.hamcrest.Matchers.equalTo;

	import java.util.ArrayList;
	import java.util.List;
	import java.util.Random;

	import org.junit.Test;

	<profiles>
	<profile>
	<id>sonar</id>
	<properties>
	<sonar.jdbc.url>jdbc:mysql://localhost:3306/sonar</sonar.jdbc.url>
	<sonar.jdbc.driver>com.mysql.jdbc.Driver</sonar.jdbc.driver>
	<sonar.jdbc.username>sonar</sonar.jdbc.username>
	<sonar.jdbc.password>xxxxx</sonar.jdbc.password>
	<!-- SERVER ON A REMOTE HOST -->
	<sonar.host.url>http://localhost:9000</sonar.host.url>