xhoong

#### Reference: https://raynix.info/archives/4296

# in the master node, run as root
kubeadm certs renew all
[renew] Reading configuration from the cluster...
[renew] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[renew] Error reading configuration from the Cluster. Falling back to default configuration

certificate embedded in the kubeconfig file for the admin to use and for kubeadm itself renewed
...

xhoong

FROM mcr.microsoft.com/mssql/server:2022-latest

USER root

RUN apt-get update && \
    apt-get install -y software-properties-common curl && \
    rm -rf /var/lib/apt/lists/*

RUN curl https://packages.microsoft.com/keys/microsoft.asc | apt-key add -
RUN add-apt-repository "$(curl https://packages.microsoft.com/config/ubuntu/20.04/mssql-server-2022.list)"

xhoong

Symmetic encryption

For symmetic encryption, you can use the following:

To encrypt:

openssl aes-256-cbc -salt -a -e -in plaintext.txt -out encrypted.txt

To decrypt:

xhoong

//https://softwaremill.com/comparing-scala-relational-database-access-libraries/
case class MetroSystemWithCity(metroSystemName: String, cityName: String, 
  dailyRidership: Int)

implicit val getMetroSystemWithCityResult = GetResult(r => 
  MetroSystemWithCity(r.nextString, r.nextString, r.nextInt))

val query = sql"""SELECT ms.name, c.name, ms.daily_ridership
                    FROM metro_system as ms
                    JOIN city AS c ON ms.city_id = c.id

xhoong

Generate ssl certificates with Subject Alt Names on OSX

We can generate a common CA certificate, and then each project can use this CA certificate to sign and issue a project certificate. Hence the CA certificate is needed to install as a trusted cert, and once the project is signed and issue using this CA cert, the new project certificate will be trusted via chain of trust policy.

Generate a CA key

openssl genrsa -out ca.key 4096

Generate a CA public key, ensure expiry date is exceeding the individual cert

xhoong

package com.softwaremill.akka

import java.time._

import akka.actor.ActorSystem
import akka.stream.ActorMaterializer
import akka.stream.scaladsl.Source

import scala.collection.mutable
import scala.concurrent.Await

xhoong

Open PostgreSQL and Create a table student in database student.

CREATE EXTENSION hstore;

CREATE TABLE student (
    id     int,
    name   varchar(254) NOT NULL,
    hobbies  text[],
    marks hstore
);

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truncate -s 0 /var/lib/docker/containers/*/*-json.log

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/**
 * Used for reading/writing to database, files, etc.
 * Code From the book "Beginning Scala"
 * http://www.amazon.com/Beginning-Scala-David-Pollak/dp/1430219890
 *  http://stackoverflow.com/a/5218279
 */
def using[A <: {def close(): Unit}, B](param: A)(f: A => B): B =
try { f(param) } finally { param.close() }

def writeToFile(fileName:String, data:String) = 

xhoong

#!/bin/sh
AMBARI_USER=admin
AMBARI_PASSWORD=
CLUSTER_NAME=sandbox
AMBARI_API=http://127.0.0.1:8080/api/v1/clusters/$CLUSTER_NAME
BLUEPRINT_API=http://127.0.0.1:8080/api/v1/blueprints

hostname="hostname.example.com"
service="aservice"