Auto-enable Local HTTP Caching in Test Kitchen

README.md

Auto-enable Local HTTP Caching in Test Kitchen

Note: total experiment and hack, looks nasty, could be awesome:

Setup

• Drop the kitchen.local.yml into $HOME/.kitchen/config.yml
• Install polipo (with Mac: brew install polipo, with Ubuntu: apt-get install polipo)
• Drop polipo-start and polipo-console somewhere useful (perhaps $HOME/bin?)

Run with HTTP Caching Proxy

Simply start up polipo in the foreground in a terminal/tmux/screen session with: ~/bin/polipo-start. In your Test Kitchen project verify that caching is enabled by running kitchen diagnose and look for the http_proxy and chef_omnibus_url config options, like in this abbreviated example output:

---
timestamp: 2015-03-06 19:27:56 UTC
kitchen_version: 1.3.1
instances:
  default-ubuntu-1204:
    state_file: {}
    driver:
      http_proxy: http://10.0.10.20:8123
      https_proxy: http://10.0.10.20:8123
      provision_command: env http_proxy=http://10.0.10.20:8123 bash -c 'curl -L
        http://www.chef.io/chef/install.sh | bash'
    provisioner:
      chef_omnibus_url: http://www.chef.io/chef/install.sh

kitchen.local.yml

<%
require 'socket'

# @return [String] public IP address of workstation used for egress traffic
def local_ip
  @local_ip ||= begin
    # turn off reverse DNS resolution temporarily
    orig, Socket.do_not_reverse_lookup = Socket.do_not_reverse_lookup, true

    UDPSocket.open do |s|
      s.connect '64.233.187.99', 1 # a google IP, does not hit network
      s.addr.last
    end
  ensure
    Socket.do_not_reverse_lookup = orig
  end
end

# @return [Integer] default polipo listening port
def local_port ; 8123 ; end

# @return [String] the polipo proxy URL
def http_proxy_url ; "http://#{local_ip}:#{local_port}" ; end

# @return [TrueClass,FalseClass] whether or not the polipo port is listening
def proxy_running?
  socket = TCPSocket.new(local_ip, local_port)
  true
rescue SocketError, Errno::ECONNREFUSED,
  Errno::EHOSTUNREACH, Errno::ENETUNREACH, IOError
  false
rescue Errno::EPERM, Errno::ETIMEDOUT
  false
ensure
  socket && socket.close
end
%>
---
<% if proxy_running? %>
driver:
  http_proxy: <%= http_proxy_url %>
  https_proxy: <%= http_proxy_url %>
  # used in kitchen-docker to pre-install/cache a Chef Ommnibus package in a
  # layer before booting containers
  provision_command: "env http_proxy=<%= http_proxy_url %> bash -c 'curl -L http://www.chef.io/chef/install.sh | bash'"

provisioner:
  # installs from an http:// source to enable better caching through
  # http_proxy, and yes, this is a bit evil
  chef_omnibus_url: http://www.chef.io/chef/install.sh
<% end %>

polipo-console

#!/usr/bin/env bash
set -e
[ -n "$DEBUG" ] && set -x

if ! command -v lynx >/dev/null ; then
  echo "$(basename $0) - lynx command not found, please install and retry"
  exit 10
fi

exec lynx "http://127.0.0.1:8123"

polipo-start

#!/usr/bin/env bash
set -e
[ -n "$DEBUG" ] && set -x

if ! command -v polipo >/dev/null ; then
  echo "$(basename $0) - polipo command not found, please install and retry"
  exit 10
fi

mkdir -p "$HOME/.polipo-cache"

exec polipo \
  proxyAddress='0.0.0.0' \
  disableIndexing='false' \
  disableServersList='false' \
  allowedClients='0.0.0.0/0' \
  diskCacheRoot='~/.polipo-cache'

Would be great if the proxy_running can exit in a quick way when polipo is not running otherwise it crawls every kitchen command.

Noticing that you catch Errno::ETIMEDOUT here but without doing anything to enforce a meaningful timeout on TCPSocket.new. By default it's 75 seconds which makes most kitchen commands unusable in the event that this gets triggered.