(CHEF) change PostgreSQL (9.2) data directory

change-postgresql-data-dir.rb

# changing the postgresql data directory is an annoyingly non-trivial and fragile operation
# this should mostly do it but there are lots of things that can go wrong and if/when they do
# you will have lots of fun trying to eradicate broken postgres installs between chef runs
# 

config_dir = "etc/postgresql/#{node[:postgresql][:version]}/main"

bash 'change_data_directory' do
  code <<-CODE
mkdir /tmp/pg_conf_backup
cp #{config_dir}/*.conf /tmp/pg_conf_backup/
pg_dropcluster --stop 9.2 main
pg_createcluster --locale=en_US.utf8 9.2 -d /data/postgresql main
cp /tmp/pg_conf_backup/*.conf #{config_dir}/
chmod 0600 #{config_dir}/postgresql.conf #{config_dir}/pg_hba.conf
sed -i -e"s:data_directory.*$:data_directory = '/data/postgresql':" #{config_dir}/postgresql.conf
  CODE
  not_if {
    ::FileTest.exist?(File.join('/data/postgresql', 'PG_VERSION'))
  }
  notifies :create, 'ruby_block[set_data_directory]', :immediately
end

ruby_block 'set_data_directory' do
  block do
    # we forcibly set the data directory for this node here, because we couldn't set it
    # earlier or it'd break the first start of postgresql (for goodness sake!)
    node.set[:postgresql][:config][:data_directory] = '/data/postgresql'
  end
  action :nothing
  notifies :start, 'service[postgresql]', :immediately
end