scriptbuilder/src/main/resources/functions/setupPublicCurl.sh

#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
alias apt-get-update="apt-get update -qq"
alias apt-get-install="apt-get install -f -y -qq --force-yes"
alias yum-install="yum --quiet --nogpgcheck -y install"

function ensure_cmd_or_install_package_apt(){
  local cmd=$1
  shift
  local pkg=$*
  
  hash $cmd 2>/dev/null || ( apt-get-update && apt-get-install $pkg )
}

function ensure_cmd_or_install_package_yum(){
  local cmd=$1
  shift
  local pkg=$*
  hash $cmd 2>/dev/null || yum-install $pkg
}

function ensure_netutils_apt() {
  ensure_cmd_or_install_package_apt nslookup dnsutils
  ensure_cmd_or_install_package_apt curl curl
}

function ensure_netutils_yum() {
  ensure_cmd_or_install_package_yum nslookup bind-utils
  ensure_cmd_or_install_package_yum curl curl
}

# most network services require that the hostname is in
# the /etc/hosts file, or they won't operate
function ensure_hostname_in_hosts() {
  [ -n "$SSH_CONNECTION" ] && {
    local ipaddr=`echo $SSH_CONNECTION | awk '{print $3}'`
  } || {
    local ipaddr=`hostname -i`
  }
  # NOTE: we blindly trust existing hostname settings in /etc/hosts
  egrep -q `hostname -s` /etc/hosts || echo "$ipaddr `hostname -f` `hostname -s`" >> /etc/hosts
}

# download locations for many services are at public dns
function ensure_can_resolve_public_dns() {
  nslookup yahoo.com | grep yahoo.com > /dev/null || echo nameserver 208.67.222.222 >> /etc/resolv.conf
}

function setupPublicCurl() {
  ensure_hostname_in_hosts
  if which dpkg &> /dev/null; then
    ensure_netutils_apt
  elif which rpm &> /dev/null; then
    ensure_netutils_yum
  else
    abort "we only support apt-get and yum right now... please contribute!"
    return 1
  fi
  ensure_can_resolve_public_dns
  return 0  
}