Revision

  $Id: webjob-pad-deploy-slackware-pkg.base,v 1.1.1.1 2007/03/19 19:39:34 klm Exp $

Purpose

  This recipe demonstrates how to deploy and verify the installation
  of a Slackware package using WebJob and PaD technology.

Motivation

  The motivation for this recipe stems from the desire/need to create
  a reliable, hands-off approach to deploying packages.

Requirements

  Cooking with this recipe requires an operational WebJob server.  If
  you do not have one of those, refer to the instructions provided in
  the README.INSTALL file that comes with the source distribution.
  The latest source distribution is available here:

    http://sourceforge.net/project/showfiles.php?group_id=40788

  Also, if you're not familiar with PaD technology, then you should
  read the background material found here:

    http://webjob.sourceforge.net/WebJob/PayloadAndDelivery.shtml

  Each client must be running UNIX and have basic system utilities,
  installpkg, removepkg, and WebJob 1.6.0 or higher installed.

  The commands presented throughout this recipe were designed to be
  executed within a Bourne shell (i.e., sh or bash).

Time to Implement

  Assuming that you have satisfied all the requirements/prerequisites,
  this recipe should take less than 30 minutes to implement.

Solution

  The solution is to use the script in Appendix 1.  The purpose of
  this script is to construct a PaD delivery command and execute it
  with WebJob.  The delivery command surveys the system to determine
  if that particular package is installed.  If not, the downloaded
  package is deployed.  However, if deployment fails, the delivery
  command will attempt to revert to the previous state by removing the
  package.  Once the package is deployed, its installation is
  verified.  The delivery command finishes by removing any temporary
  files.  This logic, in script form, is presented here:

    ${SURVEY} || { { ${DEPLOY} || ${REVERT} } && ${VERIFY} } ;
    ${FINISH}

  Each of these variables can be thought of as a macro that implements
  one particular operation.  As such, each variable can contain one or
  more commands and associated shell logic.

  The following steps describe how to implement this solution.

  1. Download, acquire, or build the Slackware package you wish to
     deploy.

  2. Before proceeding, you need to define the following variables:
     PKG_FILE and PAD_FILE.  These variables are referenced at
     various points in the remaining steps.

       $ PKG_FILE=noname-i386-1.tgz
       $ PAD_FILE=${PKG_FILE}.pad

  3. Construct a PaD script from the package file.

       $ pad-make-script --create ${PKG_FILE} > ${PAD_FILE}

  4. Copy the PaD script to the WebJob server.  Typically, it would go
     in the client's commands directory.  However, if multiple clients
     will be involved, it should go in the common commands directory.
     The permissions on the PaD script should be set to mode 0644.
     The following commands show how this could be done using scp as
     the file transfer agent.

       $ LOCATION=/var/webjob/profiles/client_1/commands/

     or

       $ LOCATION=/var/webjob/profiles/common/commands/

       $ chmod 0644 ${PAD_FILE}
       $ scp -p ${PAD_FILE} you@your.webjob.server.net:${LOCATION}

  5. Extract the script from Appendix 1, and install it in a suitable
     location (e.g., /usr/local/bin) on each client system.  Set the
     file's mode to 0755.  Use the following command to extract the
     script:

       $ sed -e '1,/^--- deploy-slackware-pkg ---$/d; /^--- deploy-slackware-pkg ---$/,$d' webjob-pad-deploy-slackware-pkg.txt > deploy-slackware-pkg

     Note: It may be necessary to modify the PATH variable, which is
     explicitly set inside the script, to suit your particular
     environment.

  6. Test deployment on a single client.  You'll need to be root
     before you run the script.

       $ ssh you@your.webjob.client.net
       # su -
       # deploy-slackware-pkg -f noname-i386-1.tgz

Closing Remarks

  To get maximum use from the script in Appendix 1, you should deploy
  it to every WebJob client.  This step, while not absolutely
  necessary, is convenient because it gives you the choice of
  installing packages manually (from the console or via remote shell)
  or automatically as a job (from the WebJob server).

  If possible, the SURVEY and VERIFY macros should be made more
  robust.  Currently, they are weak in the sense that they only test
  the existence of the specified package file in /var/log/packages/.

Author

  This recipe was brought to you by Klayton Monroe.

Credits

  This work is based on previous works created (in part or whole) by
  the following people:

    Bair, Andy
    Monroe, Klayton

Appendix 1

--- deploy-slackware-pkg ---
#!/bin/sh
######################################################################
#
# $Id: deploy-slackware-pkg,v 1.1.1.1 2007/03/19 19:39:34 klm Exp $
#
######################################################################
#
# Copyright 2007-2007 The WebJob Project, All Rights Reserved.
#
######################################################################
#
# Purpose: Deploy Slackware packages via WebJob.
#
######################################################################

IFS=' 	
'

PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin

PROGRAM=`basename "$0"`

Usage()
{
  echo 1>&2
  echo "Usage: ${PROGRAM} [-c webjob-config] [-H webjob-home] -f pad-file" 1>&2
  echo 1>&2
  exit 1
}

PAD_FILE=

while getopts "c:f:H:" OPTION; do
  case ${OPTION} in
  c) WEBJOB_CONFIG="${OPTARG}"
    ;;
  f) PAD_FILE="${OPTARG}"
    ;;
  H) WEBJOB_HOME="${OPTARG}"
    ;;
  *) Usage
    ;;
  esac
done

if [ -z "${PAD_FILE}" ]; then
  Usage
else
  PKG_FILE=`basename "${PAD_FILE}" .pad`
  PKG_NAME=`basename "${PKG_FILE}" .tgz`
fi

PATH=${PATH}:${WEBJOB_HOME=/usr/local/webjob}/bin
export PATH

SURVEY="
{
  echo 'Surveying...' 1>&2 ;
  if [ -f /var/log/packages/${PKG_NAME} ] ; then
    true ;
  else
    false ;
  fi
}"

DEPLOY="
{
  echo 'Deploying...' 1>&2 ;
  installpkg ${PKG_FILE} ;
}"

VERIFY="
{
  echo 'Verifying...' 1>&2 ;
  if [ -f /var/log/packages/${PKG_NAME} ] ; then
    true ;
  else
    false ;
  fi
}"

REVERT="
{
  echo 'Reverting...' 1>&2 ;
  removepkg ${PKG_NAME} ;
  false ;
}"

FINISH="
{
  echo 'Finishing...' 1>&2 ;
  rm -f %payload ;
}"

PAD_COMMAND="
{
  ${SURVEY} || { { ${DEPLOY} || ${REVERT} } && ${VERIFY} } ;
  ${FINISH}
}"

webjob -e -f ${WEBJOB_CONFIG-${WEBJOB_HOME}/etc/upload.cfg} ${PAD_FILE} ${PAD_COMMAND}

--- deploy-slackware-pkg ---