aaronlifton3

# to install the latest stable version:
brew install scala --with-docs

# to install scala-2.10.0-RC1:
brew install https://raw.github.com/gist/3939012/scala.rb --with-docs

# to switch versions (from https://github.com/mxcl/homebrew/wiki/External-Commands):
brew switch scala 2.9.2
brew switch scala 2.10.0-RC1

aaronlifton3

Setting Up Clojure on OS X

I spent a lot of time trying to find a pretty optimal (for me) setup for Clojure… at the same time I was trying to dive in and learn it. This is never optimal; you shouldn't be fighting the environment while trying to learn something.

I feel like I went through a lot of pain searching Google, StackOverflow, blogs, and other sites for random tidbits of information and instructions.

This is a comprehensive "what I learned and what I ended up doing" that will hopefully be of use to others and act as a journal for myself if I ever have to do it again. I want to be very step-by-step and explain what's happening (and why) at each step.

Step 1: Getting Clojure (1.3)

aaronlifton3

type 'a monoid = {zero : 'a; plus : 'a -> 'a -> 'a}
let sum (m : 'a monoid) (l : 'a list) : 'a = List.fold_left m.plus m.zero l
let string_summer = sum {zero = ""; plus = (^)}
let int_summer = sum {zero = 0; plus = (+)}

aaronlifton3

type 'a monoid = {zero : 'a; plus : 'a -> 'a -> 'a}
let sum (m : 'a monoid) (l : 'a list) : 'a = List.fold_left m.plus m.zero l
let string_summer = sum {zero = ""; plus = (^)}
let int_summer = sum {zero = 0; plus = (+)}

aaronlifton3

---
- hosts: server
  user: app_user
  gather_facts: False
  vars:
    user: app_user
    home_directory: "/home/{{ user }}"
    deploy_to: "{{ home_directory }}/app"

  roles:

aaronlifton3

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

aaronlifton3

data_bag("vhosts").each do |site|
  site_data = data_bag_item("vhosts", site)
  site_name = site_data["id"]
  document_root = "/srv/apache/#{site_name}"
 
  template "/etc/httpd/conf.d/#{site_name}.conf" do
    source "custom-vhosts.erb"
    mode "0644"
    variables(
      :document_root => document_root,

aaronlifton3

Sessions and Conversations

HTTP is a stateless protocol. Sessions allow us to chain multiple requests together into a conversation between client and server.

Sessions should be an option of last resort. If there's no where else that the data can possibly go to achieve the desired functionality, only then should it be stored in the session. Sessions can be vulnerable to security threats from third parties, malicious users, and can cause scaling problems.

That doesn't mean we can't use sessions, but we should only use them where necessary.

Adding, Accessing, and Removing Data

aaronlifton3

cd ~
sudo yum update
sudo yum install java-1.7.0-openjdk.i686 -y

wget https://github.com/downloads/elasticsearch/elasticsearch/elasticsearch-0.19.9.tar.gz -O elasticsearch.tar.gz

tar -xf elasticsearch.tar.gz
rm elasticsearch.tar.gz
mv elasticsearch-* elasticsearch
sudo mv elasticsearch /usr/local/share

aaronlifton3

# download latest libevent2 and tmux sources, and extract them somewhere
# (thx bluejedi for tip on latest tmux URL)
#
# at the time of writing:
# https://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz
# http://sourceforge.net/projects/tmux/files/latest/download?source=files
# 

# install deps
yum install gcc kernel-devel make ncurses-devel