nttuyen

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

nttuyen

FWIW: I (@rondy) am not the creator of the content shared here, which is an excerpt from Edmond Lau's book. I simply copied and pasted it from another location and saved it as a personal note, before it gained popularity on news.ycombinator.com. Unfortunately, I cannot recall the exact origin of the original source, nor was I able to find the author's name, so I am can't provide the appropriate credits.

---

Effective Engineer - Notes

• By Edmond Lau
• Highly Recommended 👍
• http://www.theeffectiveengineer.com/

What's an Effective Engineer?

nttuyen

Pattern below allows for a bash script to be called via, say, cron and check to see if it is already running.

Useful for things like rsync tasks.

PIDFILE=/var/run/myscriptname.pid

if [ -f $PIDFILE ]
then
 PID=$(cat $PIDFILE)

nttuyen

# Backup
docker exec CONTAINER /usr/bin/mysqldump -u root --password=root DATABASE > backup.sql

# Restore
cat backup.sql | docker exec -i CONTAINER /usr/bin/mysql -u root --password=root DATABASE

nttuyen

<?php

/**
 * PDO Session Handler
 * @author Daniel15 <dan.cx>
 *
 * modificata da carlo@chierotti.net
 * per gestire la scadenza della sessione
 *
 * testata in PHP53, se si passa a PHP54 si potrebbe utilizzare