Angel skozz

#Heroku, Ruby on Rails and PhantomJS

In this post, I’m going to show you how to modify an existing Ruby on Rails app running on Heroku’s Cedar stack to use PhantomJS for screen scraping. If you’ve never heard of PhantomJS, it’s a command-line WebKit-based browser (that supports JavaScript, cookies, etc.).

Let’s get started. This is a high-level overview of the required steps:

Modify your app to use multiple Heroku buildpacks.
Extend your app to use both the Ruby as well as the PhantomJS buildpacks.
Confirm that everything worked.

Lambda: standard

# Creating a lambda
l = lambda { |name| "Hi #{name}!" }

# Executing the lambda
l.call("foo") # => Hi foo!

Business Models

Advertising

Models	Examples
Display ads	Yahoo!
Search ads	Google

Screen Quick Reference

Basic

Description	Command
Start a new session with session name	`screen -S <session_name>`
List running sessions / screens	`screen -ls`
Attach to a running session	`screen -x`
Attach to a running session with name	`screen -r`

	class Person < ActiveRecord::Base

	# This manual SQL query...
	scope :allowed_to_eat_cheese, joins(
	<<-SQL
	INNER JOIN cities ON people.city_id = cities.id
	INNER JOIN states ON cities.state_id = states.id
	SQL
	).where('states.allows_cheese_consumption' = 'Yeppers')

	require 'test_helper'

	# testing rake task app:awesome_report
	# defined in file lib/tasks/app/awesome_report.rake

	describe 'App::AwesomeReportTaskTest' do
	it 'generates the awesomeness report' do
	subject.invoke
	assert File.exists?('awesomeness_report.csv')
	end

	##################################################################
	# /etc/elasticsearch/elasticsearch.yml
	#
	# Base configuration for a write heavy cluster
	#

	# Cluster / Node Basics
	cluster.name: logng

	# Node can have abritrary attributes we can use for routing

	build:
	steps:
	- script:
	name: seed the database
	code: rake db:seed
	- script:
	name: example multiple commands
	code: \|
	export TEST_VAR=12345
	cat $TEST > test.txt

	Geocoder.configure(:lookup => :test)

	Geocoder::Lookup::Test.set_default_stub(
	[
	{
	'latitude' => 40.7143528,
	'longitude' => -74.0059731,
	'address' => 'New York, NY, USA',
	'state' => 'New York',
	'state_code' => 'NY',

	/*
	Only allow users with a verified email address on a pre-verified domain to log in.

	We're getting people to authenticate and only authorising those that have an email we recognise.

	Assumes a Meteor.settings like:
	{ adminDomains: ['tableflip.io', 'meteor.com'] }

	...and meteor-developer accounts, but other login mechanisms (email, twitter) would work too.
	*/