intech

#!/bin/bash

useradd -m -d /home/$USER -s /bin/bash $USER
sudo -u$USER mkdir -p /home/$USER/.ssh
chmod 700 /home/$USER/.ssh
sudo -u$USER touch /home/$USER/.ssh/authorized_keys
chmod 600 /home/$USER/.ssh/authorized_keys
# Docker
usermod -aG docker $USER

intech

// broker.js
"use strict";

const { ServiceBroker } = require("moleculer");
const Sequelize = require("./middlewares/sequelize");
const broker = new ServiceBroker({
	middlewares: [Sequelize()]
});
broker.createService({
	name: "service",

intech

for i in $(seq 1 3);
do 
  docker-compose pull roach$i
  docker-compose exec roach$i /cockroach/cockroach quit --insecure
  docker-compose up -d --build roach$i
done

intech

require("http").request({host:"localhost",port:80,timeout:2000},res=>process.exit(res.statusCode!==200)).on("error",()=>process.exit(1));

intech

#!/bin/sh -e

if [ $# != 3 ]
then
    echo "usage: $0 <src-port> <dst-host> <dst-port>"
    exit 0
fi

TMP=`mktemp -d`
PIPE=$TMP/pipe

intech

Unique hex-string (time+random) with fixed length 11:

(Math.round(Math.random() * 0x10000) + Date.now()).toString(16)
// 16c8e982dcd
// 16c95dc3c76
// 16cb7307195

Unique string (time+random) with fixed length 8:

intech

Networking-streams

servers and clients

Any networked computer can be a server Any networked computer can be a client

Package a put in a little pieces.

tc vs udp

TCP - reliable transport: has ACK

intech

███╗   ███╗ ██████╗ ██╗     ███████╗ ██████╗██╗   ██╗██╗     ███████╗██████╗
████╗ ████║██╔═══██╗██║     ██╔════╝██╔════╝██║   ██║██║     ██╔════╝██╔══██╗
██╔████╔██║██║   ██║██║     █████╗  ██║     ██║   ██║██║     █████╗  ██████╔╝
██║╚██╔╝██║██║   ██║██║     ██╔══╝  ██║     ██║   ██║██║     ██╔══╝  ██╔══██╗
██║ ╚═╝ ██║╚██████╔╝███████╗███████╗╚██████╗╚██████╔╝███████╗███████╗██║  ██║
╚═╝     ╚═╝ ╚═════╝ ╚══════╝╚══════╝ ╚═════╝ ╚═════╝ ╚══════╝╚══════╝╚═╝  ╚═╝

intech

leveldb

am e,bedded key/value database. Is good to be a modular database. If you wanna run applications on browser as well as in node.

its embedded it is in the same process. It lives in the program. It was built for chrome.

install

Since leveldb is a standalone database, you can install it with npm:

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describe("Test route.path and aliases", () => {
	let broker;
	let app;
	let service;
	let nextHandler = jest.fn((req, res) => res.sendStatus(200));

	beforeAll(() => {

		broker = new ServiceBroker({ logger: false });