Joseworks

##How Homakov hacked GitHub and the line of code that could have prevented it

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Please note: THIS ARTICLE IS NOT WRITTEN BY THE GITHUB TEAM or in any way associated with them. It's simply hosted as a Gist because the markdown formatting is excellent and far clearer than anything I could manage on my personal Tumblr at peternixey.com.

If you'd like to follow me on twitter my handle is @peternixey

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Joseworks

Render and Redirect

The normal controller/view flow is to display a view template corresponding to the current controller action, but sometimes we want to change that. We use render in a controller when we want to respond within the current request, and redirect_to when we want to spawn a new request.

Render

The render method is very overloaded in Rails. Most developers encounter it within the view template, using render :partial => 'form' or render @post.comments, but here we'll focus on usage within the controller.

:action

Joseworks

1) see re: increasing shmmax http://stackoverflow.com/a/10629164/1283020

2) add to postgresql.conf:
shared_preload_libraries = 'pg_stat_statements'   # (change requires restart)
136 pg_stat_statements.max = 1000
137 pg_stat_statements.track = all

3) restart postgres

4) check it out in psql

Joseworks

#!/usr/bin/env ruby

# If you get "unknown OID 705: failed to recognize type of '<field>'. It will be treated as String."
# it probably means that type of column could not be identified when retriving records

# Example
User.where("'something' as something") 

# Will results in unknown OID. However doing this:

Joseworks

After automatically updating Postgres to 9.6.1 via Homebrew, the pg_ctl start command didn't work.
The error was something like "database files are incompatible with server".

Database files have to be updated before starting the server, here are the steps that had to be followed:

# need to have both 9.6.1 and latest 9.5.x installed, and keep 9.6.1 as default
brew unlink postgresql
brew install postgresql95
brew unlink postgresql95
brew link postgresql

Joseworks

A summary of the Rails Guides on Routes, plus other tips.

The Rails router recognizes URLs and dispatches them to a controller's action. It can also generate paths and URLs, avoiding the need to hardcode strings in your views.

Examples

# Redirects /orders/report to orders#report.
get 'orders/report', to: 'orders#report'

Joseworks

require "rubygems"

require "rack"
require "middleman/rack"
require "rack/contrib/try_static"

protected_middleman = Rack::Auth::Basic.new(Middleman.server) do |username, password|
  [username, password] == [ENV['HTTP_USERNAME'], ENV['HTTP_PASSWORD']]
  # Enable proper HEAD responses
  use Rack::Head

Joseworks

require 'rubygems'
require 'middleman/rack'
 
protected_middleman = Rack::Auth::Basic.new(Middleman.server) do |username, password|
  [username, password] == ['theuser', 'thepassword']
end
 
run protected_middleman

Joseworks

#!/usr/bin/env ruby

progress = 'Progress ['
1000.times do |i|

# i is number from 0-999
j = i + 1

  # add 1 percent every 10 times
  if j % 10 == 0

Joseworks

#!/usr/bin/env ruby

progress = 'Progress ['
1000.times do |i|

# i is number from 0-999
j = i + 1

  # add 1 percent every 10 times
  if j % 10 == 0