Indro De indrode

Adding an audit log to your Rails app

If you have any sort of administrative interface on your web site, you can easily imagine an intruder gaining access and mucking about. How do you know the extent of the damage? Adding an audit log to your app is one quick solution. An audit log should record a few things:

controller entry points with parameter values
permanent information about the user, like user_id
transient information about the user, like IP and user_agent

Using the Rails framework, this is as simple as adding a before_action to your admin controllers. Here’s a basic version that I’m using in production.

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

ruby-1.9.3-p327 cumulative performance patch for rbenv

This installs a patched ruby 1.9.3-p327 with various performance improvements and a backported COW-friendly GC, all courtesy of funny-falcon.

Requirements

You will also need a C Compiler. If you're on Linux, you probably already have one or know how to install one. On OS X, you should install XCode, and brew install autoconf using homebrew.

	require 'date'
	require 'koala'

	class BirthdayLiker
	FACEBOOK_TOKEN = 'your_oauth_key'
	BIRTHDAY_WORDS = %w(birthday bday birfday birth born)
	THANKS_OPTIONS = ['Thank you!', 'Thanks!', 'Appreciate it!']
	DATE_TIME_FORMAT = '%Y-%m-%d'

	def initialize(birthdate, opts={})

	module DefaultValues

	def has_default_values(default_values = {})

	class_attribute :default_values
	self.default_values = default_values

	after_initialize :assign_default_values

	include InstanceMethods

	# Kill and restart nginx
	function restart_nginx(){
	pids=$(pidof nginx)
	if [[ -n $pids ]];
	then
	sudo kill -9 $pids
	sudo service nginx restart
	fi
	}

	=Navigating=
	visit('/projects')
	visit(post_comments_path(post))

	=Clicking links and buttons=
	click_link('id-of-link')
	click_link('Link Text')
	click_button('Save')
	click('Link Text') # Click either a link or a button
	click('Button Value')

	# MAC manipulators
	alias random_mac='sudo ifconfig en0 ether `openssl rand -hex 6 \| sed "s/\(..\)/\1:/g; s/.$//"`'
	alias restore_mac='sudo ifconfig en0 ether YOUR_ORIGINAL_MAC_ADDRESS_GOES_HERE'