Yogesh Agrawal saggiyogesh

In computing, memoization or memoisation
is an optimization technique used primarily
to speed up computer programs by storing
the results of expensive function calls and
returning the cached result when the same
inputs occur again.
— wikipedia

ffmpeg

Converting Audio into Different Formats / Sample Rates

Minimal example: transcode from MP3 to WMA:
ffmpeg -i input.mp3 output.wma

You can get the list of supported formats with:
ffmpeg -formats

You can get the list of installed codecs with:

Virtual Hosts on nginx (CSC309)

When hosting our web applications, we often have one public IP address (i.e., an IP address visible to the outside world) using which we want to host multiple web apps. For example, one may wants to host three different web apps respectively for example1.com, example2.com, and example1.com/images on the same machine using a single IP address.

How can we do that? Well, the good news is Internet browsers

Setting up a SSL Cert from Comodo

I use Namecheap.com as a registrar, and they resale SSL Certs from a number of other companies, including Comodo.

These are the steps I went through to set up an SSL cert.

Purchase the cert

AngularJS Directive Attribute Binding Explanation

When using directives, you often need to pass parameters to the directive. This can be done in several ways. The first 3 can be used whether scope is true or false. This is still a WIP, so validate for yourself.

Raw Attribute Strings

<div my-directive="some string" another-param="another string"></div>

	// This script is executed in mongo shell to replace all occurence of a STRING, with an objectId string
	// and then using parse, converting objectId string to actual objectId

	db.Dummy.find({}).forEach(function(doc) {
	console.log(doc._id);
	let newDoc = JSON.stringify(doc).replace('STRING', '5ab23ff3423159ad5d0251c0');
	print('newDoc', newDoc);

	let jsonDoc = JSON.parse(newDoc, (key, value) => {
	if (value === '5ab23ff3423159ad5d0251c0') {

	#!/bin/sh
	# OUTDATED: please refer to the link below for the latest version:
	# https://github.com/rancherlabs/support-tools/blob/master/extended-rancher-2-cleanup/extended-cleanup-rancher2.sh
	docker rm -f $(docker ps -qa)
	docker volume rm $(docker volume ls -q)
	cleanupdirs="/var/lib/etcd /etc/kubernetes /etc/cni /opt/cni /var/lib/cni /var/run/calico /opt/rke"
	for dir in $cleanupdirs; do
	echo "Removing $dir"
	rm -rf $dir
	done

	http {
	log_format bodylog '$remote_addr - $remote_user [$time_local] '
	'"$request" $status $body_bytes_sent '
	'"$http_referer" "$http_user_agent" $request_time '
	'<"$request_body" >"$resp_body"';

	lua_need_request_body on;

	set $resp_body "";
	body_filter_by_lua '

	function encodeURI(str)
	if (str) then
	str = string.gsub (str, "\n", "\r\n")
	str = string.gsub (str, "([^%w ])",
	function (c) return string.format ("%%%02X", string.byte(c)) end)
	str = string.gsub (str, " ", "+")
	end
	return str
	end