khun84

require 'openssl'

key = OpenSSL::PKey::RSA.new(2048)
p encrypted_string = key.public_encrypt('my plaintext string', OpenSSL::PKey::RSA::PKCS1_OAEP_PADDING)
p decrypted_string = key.private_decrypt(encrypted_string, OpenSSL::PKey::RSA::PKCS1_OAEP_PADDING)

khun84

Mac OS X SSH client autocomplete for hosts

Snippet for ~/.bash_profile, adding hostname autocomplete to ssh.

Extracts host hints from both ~/.ssh/config and /etc/hosts.

function __completeSSHHosts {
	COMPREPLY=()
	local currentWord=${COMP_WORDS[COMP_CWORD]}
	local completeHosts=$(

khun84

import pandas as pd
import folium

# edit this section to project the polygon that you want
pj_geojson = {"type":"Polygon","coordinates":[[[101.6637271,3.070996],[101.6637271,3.204971],[101.5526301,3.204971],[101.5526301,3.070996],[101.6637271,3.070996]]]}
subang_jaya = {"type":"Polygon","coordinates":[[[101.6210431,3.085025],[101.6210431,2.975538],[101.5493918,2.975538],[101.5493918,3.085025],[101.6210431,3.085025]]]}
langat = {"type":"Polygon","coordinates":[[[101.6828061,2.643176],[101.6828061,2.9793898],[101.2863841,2.9793898],[101.2863841,2.643176],[101.6828061,2.643176]]]}

boundary = pj_geojson['coordinates'][0]
boundary2 = subang_jaya['coordinates'][0]

khun84

ServiceMatch table housekeeping

Steps:

1. Provision snapshot instance with same production spec

3. Create archived service match table in another namespace
4. Export service matches that are to be archived (via pg_dump or copy) into flat file (to be performed using psql in one of the prod application instance)
5. Load archived service matches from flat file into archive table (via pg_restore or copy)
6. Hard delete service matches to be archived in production DB by using batch strategy

khun84

Guides

1. Uninstall and install openssl version 1.0.2. As openssl v1.0.2 is no longer available, I have extracted openssl v1.0.2 and make it available at https://github.com/khun84/homebrew-repo/

brew uninstall --force --ignore-dependencies openssl
brew install khun84/homebrew-repo/openssl
brew cleanup # in case it fails due to permission denied, it can be due to the symlink to be removed is pointing to a non-exist file/directory. Just create the corresponding file or directory and run this command again

2. After OpenSSL installation, check it using pkg-config --libs openssl. You should see something like -L/usr/local/Cellar/openssl/1.0.2t/lib -lssl -lcrypto

khun84

Steps

Somewhat helpful link: https://developers.google.com/api-client-library/ruby/

Go to: https://console.developers.google.com/iam-admin/projects
Click "+Create Project"
Enter a "Project name" and "Project ID" and click "Create"
Under "Library" select "Calendar API"
Click ">Enable"
Return to: https://console.developers.google.com/iam-admin/projects

Click "Service Accounts"

khun84

filepath = 'local-filepath'
url = 'web-url'
File.open(filepath, 'w') {|f|
    block = proc { |response|
      response.read_body do |chunk|
        puts "Working on response" 
        f.write chunk
      end
    }
    RestClient::Request.new(method: :get, url: url, block_response: block).execute

khun84

For the system Java wrappers to find this JDK, symlink it with
  sudo ln -sfn /usr/local/opt/openjdk/libexec/openjdk.jdk /Library/Java/JavaVirtualMachines/openjdk.jdk

openjdk is keg-only, which means it was not symlinked into /usr/local,
because it shadows the macOS `java` wrapper.

If you need to have openjdk first in your PATH run:
  echo 'export PATH="/usr/local/opt/openjdk/bin:$PATH"' >> /Users/Daniel/.bash_profile

khun84

Fix corrupted cached packages

If bump into errors similar to the following during apt install

Preparing to unpack .../libllvm3.8v4_1%3a3.8-2ubuntu3~trusty4_i386.deb ...
Unpacking libllvm3.8v4:i386 (1:3.8-2ubuntu3~trusty4) ...
dpkg: error processing archive /var/cache/apt/archives/libllvm3.8v4_1%3a3.8-2ubuntu3~trusty4_i386.deb (--unpack):
 trying to overwrite '/usr/lib/i386-linux-gnu/libLLVM-3.8.so.1', which is also in package libllvm3.8:i386 1:3.8~+rc3-1~exp1~gd~t
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)

khun84

The reason of this issue is here => https://www.openssl.org/blog/blog/2021/09/13/LetsEncryptRootCertExpire/

So basically we can just remove the expired cert from the ssl cert file as suggested here => https://www.linuxadictos.com/en/ya-iniciaron-los-problemas-generados-por-el-certificado-dst-root-ca-x3.html

My ssl cert file is located in /etc/ssl/cert.pem. I just need to look for the expired cert and comment it out.

Since Im using ruby 2.3.1 which is using openssl 1.0.2t and I dont want to recompile it, I can use the env var SSL_CERT_FILE to tell which ssl cert i want to use in ruby runtime.