dongnguyenltqb

struct Draft {}
struct PendingReview {}
struct Published {}
struct Post {
    state: Option<Box<dyn State>>,
    content: String,
}

// self: Box<Self> "This syntax means the method is only valid when called on a Box holding the type."
trait State {

dongnguyenltqb

FROM jenkins/jenkins:2.331-jdk11
USER root
RUN apt-get update && apt-get install -y lsb-release zip unzip
RUN curl -fsSLo /usr/share/keyrings/docker-archive-keyring.asc \
  https://download.docker.com/linux/debian/gpg
RUN echo "deb [arch=$(dpkg --print-architecture) \
  signed-by=/usr/share/keyrings/docker-archive-keyring.asc] \
  https://download.docker.com/linux/debian \
  $(lsb_release -cs) stable" > /etc/apt/sources.list.d/docker.list
RUN apt-get update && apt-get install -y docker-ce-cli

dongnguyenltqb

Local Development Techniques with Kubernetes

This talk is all live demos of tools developers can use in their inner-loop, at development time to be more productive with containers.

Start Easier

Docker Compose captures the build arguments and run arguments so we can focus on our coding.

dongnguyenltqb

version: "2"

services:
  zookeeper:
    image: docker.io/bitnami/zookeeper:3.7
    networks:
      - kiko
    ports:
      - "2181:2181"
    volumes:

dongnguyenltqb

package main

import (
	"fmt"

	"github.com/jinzhu/gorm"
	_ "github.com/lib/pq"
)

func main() {

dongnguyenltqb

web:
  image: 'gitlab/gitlab-ce:latest'
  restart: always
  hostname: 'git.dongnguyen.dev'
  environment:
    GITLAB_OMNIBUS_CONFIG: |
      external_url  'https://git.dongnguyen.dev'
      nginx['listen_port'] = 80
      nginx['listen_https'] = false
      gitlab_rails['gitlab_shell_ssh_port'] = 24

dongnguyenltqb

[Unit]
Description=Setup a secure tunnel
After=network.target

[Service]
ExecStart=/usr/bin/ssh -NT -v -o ServerAliveInterval=60 -o ExitOnForwardFailure=yes  -o StrictHostKeyChecking=no -i /home/dong/key.pem  -R 0.0.0.0:22:localhost:22 dong@dongnguyen.dev

# Remote Burst, restart to die
StartLimitBurst=500000
StartLimitIntervalSec=10000

dongnguyenltqb

# Golang - Building Executables for Different Architectures

env GOOS=**target-OS** GOARCH=**target-architecture** go build **package-import-path**

```sh
# Example
env GOOS=darwin GOARCH=amd64 go build
env GOOS=darwin GOARCH=amd64 go build main.go
env GOOS=darwin GOARCH=amd64 go build github.com/zoo/york/foo/bar

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# Performing UDP tunneling through an SSH connection

------

## Intro

The Swiss ISP [Bluewin](http://www.bluewin.ch/) sucks. Their DNS are often down. A friend even received advice from Bluewin technicians to not use their own DNS!... But then, it is quite hard to gain access to another DNS for free, if you don't have access to a co hosted machine.

In this document, we'll access another machine's network internal DNS services (UDP port 53) with only SSH access to it. We will forward local UDP/53 traffic to TCP, then TCP traffic with the port-forwarding mechanism of SSH to the other machine, then TCP to UDP/53 on the other end. Typically, you can do it with [openvpn](http://openvpn.net/). But here, we'll do it with simpler tools, only [openssh](http://www.openssh.com/) and [netcat](http://m.nu/program/util/netcat/netcat.html).

dongnguyenltqb

const { Pool } = require("pg");
const connectionString = process.env.db_uri || "postgres://localhost:5432/postgres";
const pool = new Pool({ connectionString });

function Locker(key, timeout, retryCount) {
  this.key = key;
  this.timeout = timeout || 200;
  this.retryCount = retryCount || 5;
  this.getClient = getClient;
  this.aquireLock = aquireLock;