Clivern

const MAX_ITEM1: i64 = 1000000;
const MAX_ITEM2: &str = "HJ";

fn main() {
    let y = 3;
    println!("y = {}", y);

    let mut x = 1;
    x += 1;
    println!("x = {}", x);

Clivern

fn main() {
    let x: i32 = 2;
    take_ownership_x(x);
    println!("x = {}", x);

    let y = String::from("Hello");
    take_ownership(y);
    // the following line shall fail since value borrowed above
    // println!("y = {}", y);

Clivern

> 

Clivern

fn main() {
    let x: Option<&str> = Some("some");
    println!("{:?}", x);
    println!("{:?}", x.unwrap());

    match x {
        Some(v) => {
            println!("v = {:?}", v);
        }
        None => {

Clivern

$ wget https://github.com/prometheus/node_exporter/releases/download/v1.3.1/node_exporter-1.3.1.linux-amd64.tar.gz
$ tar xvfz node_exporter-*.*-amd64.tar.gz
$ sudo mv node_exporter-*.*-amd64/node_exporter /usr/local/bin/

$ sudo useradd -rs /bin/false node_exporter

Clivern

Edit /etc/rc.local

python /root/program.py &
DISPLAY=:1 chromium-browser --kiosk http://127.0.0.0.1:8000

python /root/program.py &
DISPLAY=:1 chromium-browser --kiosk https://clivern.com

Clivern

HTTP Web Server

const server = require('http')
const SERVER_PORT = process.argv[2]  || 8000

server.createServer(function (req, res) {
    res.writeHead(200, {'content-type': 'text/plain'});
    res.end("Hello, World\n");
}).listen(SERVER_PORT);

Clivern

#!/bin/bash

sudo apt update
sudo apt upgrade -y
sudo apt install openjdk-8-jdk apt-transport-https -y
java -version
sudo sh -c 'echo "deb http://www.apache.org/dist/cassandra/debian 40x main" > /etc/apt/sources.list.d/cassandra.list'
wget -q -O - https://www.apache.org/dist/cassandra/KEYS | sudo apt-key add -
sudo apt update
sudo apt install Cassandra

Clivern

Setup Docker

$ apt-get update
$ apt-get install docker.io -y
$ systemctl enable docker

Python

Clivern

class Node:
	def __init__(self, data=None, next=None):
		self.data = data
		self.next = next

	def __repr__(self):
		return repr(self.data)