Chi-I Huang chiihuang

System Design Cheatsheet

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

Basic Steps

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?

Are you setup and ready?

To get the most out of the Twitter Ads API workshop, make sure you come with your laptop ready to go. This workshop relies on your participation and there are just a few things you need to have ready ahead of time to make sure your development environment is setup and ready to go.

1. Install Ruby

For OS X and Unix users:

OS X and most unix-based platforms come ready to go with what you'll need to participate in this workshop. Just make sure you've got Ruby 2.0.0 or higher by running ruby -v from your terminal.

ANNOUNCEMENT

I have moved this over to the Tech Interview Cheat Sheet Repo and has been expanded and even has code challenges you can run and practice against!

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Better local require() paths for Node.js

Problem

When the directory structure of your Node.js application (not library!) has some depth, you end up with a lot of annoying relative paths in your require calls like:

const Article = require('../../../../app/models/article');

Those suck for maintenance and they're ugly.

Possible solutions

#MongoDB - Basics

##Installation The Debian package management tool (i.e. dpkg and apt) ensure package consistency and authenticity by requiring that distributors sign packages with GPG keys. Issue the following command to import the 10gen public GPG Key:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv 7F0CEB10

Create a /etc/apt/sources.list.d/10gen.list file using the following command.

echo 'deb http://downloads-distro.mongodb.org/repo/debian-sysvinit dist 10gen' | sudo tee /etc/apt/sources.list.d/10gen.list

	# enable "sandbox" mode
	CLIENT.options[:sandbox] = true

	# load your sandbox account object
	account = CLIENT.accounts.first

	# create your campaign
	campaign = TwitterAds::Campaign.new(account)
	campaign.funding_instrument_id = account.funding_instruments.first.id
	campaign.daily_budget_amount_local_micro = 1_000_000

	Homebrew - Scala 2.10.4

	Install Tapped version of Scala 2.10.4 (old version)
	> brew install homebrew/versions/scala210

	Unlink version of Scala 2.11 (if installed)
	> brew unlink scala

	Link Tapped version of Scala 2.10.4
	> brew link scala210 --force

	#!/bin/bash

	MONGO_DATABASE="your_db_name"
	APP_NAME="your_app_name"

	MONGO_HOST="127.0.0.1"
	MONGO_PORT="27017"
	TIMESTAMP=`date +%F-%H%M`
	MONGODUMP_PATH="/usr/bin/mongodump"
	BACKUPS_DIR="/home/username/backups/$APP_NAME"

	listen l1
	bind 0.0.0.0:80
	mode tcp
	timeout connect 4000
	timeout client 180000
	timeout server 180000
	server srv1 192.168.1.1:80

	global
	user "nobody"

	{
	"IAB1": "Arts & Entertainment",
	"IAB1-1": "Books & Literature",
	"IAB1-2": "Celebrity Fan/Gossip",
	"IAB1-3": "Fine Art",
	"IAB1-4": "Humor",
	"IAB1-5": "Movies",
	"IAB1-6": "Music",
	"IAB1-7": "Television",
	"IAB2": "Automotive",