Omnibus Bootstrap Template, latest version I use.

omnibus.erb

# Refer to CHEF-2815. http://tickets.opscode.com/browse/CHEF-2815

bash -c '
<%= "export http_proxy=\"#{knife_config[:bootstrap_proxy]}\"" if knife_config[:bootstrap_proxy] -%>

exists() {
  if command -v $1 &>/dev/null
  then
    return 0
  else
    return 1
  fi
}

install_sh="http://opscode.com/chef/install.sh"

if ! exists /usr/bin/chef-client; then
  if exists wget; then
    wget <%= "--proxy=on " if knife_config[:bootstrap_proxy] %> ${install_sh} -O - | bash
  else
    if exists curl; then
      curl <%= "--proxy=on " if knife_config[:bootstrap_proxy] %> ${install_sh} | bash
    fi
  fi
fi

mkdir -p /etc/chef

(
cat <<'EOP'
<%= validation_key %>
EOP
) > /tmp/validation.pem
awk NF /tmp/validation.pem > /etc/chef/validation.pem
rm /tmp/validation.pem


<% if @chef_config[:encrypted_data_bag_secret] -%>
(
cat <<'EOP'
<%= encrypted_data_bag_secret %>
EOP
) > /tmp/encrypted_data_bag_secret
awk NF /tmp/encrypted_data_bag_secret > /etc/chef/encrypted_data_bag_secret
rm /tmp/encrypted_data_bag_secret
<% end -%>

(
cat <<'EOP'
<%= config_content %>
EOP
) > /etc/chef/client.rb

(
cat <<'EOP'
<%= { "run_list" => @run_list }.to_json %>
EOP
) > /etc/chef/first-boot.json

<%= start_chef %>'