#!/bin/sh
#
#	High-Availability Apache/IBMhttp control script
# 
# apache (aka IBMhttpd)
#
# Description:	starts/stops apache web servers.
#
# Author:	Alan Robertson
#		Sun Jiang Dong
#
# Support:	linux-ha@lists.linux-ha.org
#
# License:	GNU General Public License (GPL)
#
# Copyright:	(C) 2002-2005 International Business Machines
#
#
# An example usage in /etc/ha.d/haresources: 
#       node1  10.0.0.170 apache::/opt/IBMHTTPServer/conf/httpd.conf
#       node1  10.0.0.170 IBMhttpd
#
# Our parsing of the Apache config files is very rudimentary.
# It'll work with lots of different configurations - but not every
# possible configuration.
#
# Patches are being accepted ;-)
#
# OCF parameters:
#  OCF_RESKEY_configfile
#  OCF_RESKEY_httpd
#  OCF_RESKEY_port
#  OCF_RESKEY_statusurl
#  OCF_RESKEY_options
#  OCF_RESKEY_testregex


. ${OCF_ROOT}/resource.d/heartbeat/.ocf-shellfuncs
HA_VARRUNDIR=${HA_VARRUN}

#######################################################################
#
#	Configuration options - usually you don't need to change these
#
#######################################################################
#
IBMHTTPD=/opt/IBMHTTPServer/bin/httpd
HTTPDLIST="/sbin/httpd2 /usr/sbin/httpd2 /usr/sbin/apache2 /sbin/httpd /usr/sbin/httpd /usr/sbin/apache $IBMHTTPD"
MPM=/usr/share/apache2/find_mpm
if
  [ -x $MPM ]
then
  HTTPDLIST="$HTTPDLIST `$MPM 2>/dev/null`"
fi

WGETOPTS="-O- -q -L"
LOCALHOST="http://localhost"
HTTPDOPTS="-DSTATUS"
DEFAULT_IBMCONFIG=/opt/IBMHTTPServer/conf/httpd.conf
DEFAULT_NORMCONFIG="/etc/apache2/httpd.conf"
#
# You can also set
#	HTTPD
#	PORT
#	STATUSURL
#	CONFIGFILE
# in this section if what we're doing doesn't work for you...
#
#	End of Configuration options
#######################################################################

CMD=`basename $0`

#	The config-file-pathname is the pathname to the configuration
#	file for this web server.  Various appropriate defaults are
#	assumed if no config file is specified.  If this command is
#	invoked as *IBM*, then the default config file name is
#	$DEFAULT_IBMCONFIG, otherwise the default config file
#	will be $DEFAULT_NORMCONFIG.
usage() {
  cat <<-!
usage: $0 action

action:
	start	start the web server

	stop	stop the web server

	status	return the status of web server, run or down

	monitor  return TRUE if the web server appears to be working.
                For this to be supported you must configure mod_status
		 and give it a server-status URL.  You have to have 
		installed $WGET for this to work.

	meta-data	show meta data message

	validate-all	validate the instance parameters
	!
  exit $1
}

apachecat() {
	awk '
	function procline() {
		split($0,a);
		if( a[1]=="Include" ) {
			procinclude(a[2]);
		} else {
			if( a[1]=="ServerRoot" ) {
				rootdir=a[2];
				gsub("\"","",rootdir);
			}
			print;
		}
	}
	function printfile(infile, a) {
		while( (getline<infile) > 0 ) {
			procline();
		}
		close(infile);
	}
	function allfiles(dir, cmd,f) {
		cmd="find -L "dir" -type f";
		while( ( cmd | getline f ) > 0 ) {
			printfile(f);
		}
		close(cmd);
	}
	function listfiles(pattern, cmd,f) {
		cmd="ls "pattern" 2>/dev/null";
		while( ( cmd | getline f ) > 0 ) {
			printfile(f);
		}
		close(cmd);
	}
	function procinclude(spec) {
		if( rootdir!="" && spec!~/^\// ) {
			spec=rootdir"/"spec;
		}
		if( isdir(spec) ) {
			allfiles(spec); # read all files in a directory (and subdirs)
		} else {
			listfiles(spec); # there could be jokers
		}
	}
	function isdir(s) {
		return !system("test -d \""s"\"");
	}
	{ procline(); }
	' $1 |
	sed 's/#.*//;s/[[:blank:]]*$//;s/^[[:blank:]]*//' |
	grep -v '^$'
}

#
# set parameters (as shell vars) from our apache config file
#
get_apache_params() {
  configfile=$1
  shift 1
  vars=`echo $@ | sed 's/ /,/g'`

  eval `
  apachecat $configfile | awk -v vars="$vars" '
  BEGIN{
    split(vars,v,",");
    for( i in v )
  	  vl[i]=tolower(v[i]);
  }
  {
	  for( i in v )
	  	if( tolower($1)==vl[i] ) {
			print v[i]"="$2
			delete vl[i]
			break
		}
  }
  '`
}

#
#	Return the location(s) that are handled by the given handler
#
FindLocationForHandler() {
  PerlScript='while (<>) {
	/<Location "?([^ >"]+)/i && ($loc=$1);
	'"/SetHandler +$2"'/i && print "$loc\n"; 
  }'
  apachecat $1 | perl -e "$PerlScript"
}

#
#	Check if the port is valid
#
CheckPort() {
  ocf_is_decimal "$1" && [ $1 -gt 0 ]
}


#
#	Get all the parameters we need from the Apache config file
#
GetParams() {
  ConfigFile=$1
  if [ ! -f $ConfigFile ]; then
  	return 1
  fi
  get_apache_params $ConfigFile ServerRoot PidFile Port Listen
  case $PidFile in
    /*)	;;
    [[:alnum:]]*)	PidFile=$ServerRoot/$PidFile;;
    *)	PidFile=$HA_VARRUNDIR/${httpd_basename}.pid;;
  esac
  if CheckPort "$PORT"; then
	:
  else
	PORT=$Port
	if CheckPort "$PORT"; then
	    :
	else
	# Final resort
	    PORT=80
	fi
  fi
  
  #
  # It's difficult to figure out whether the server supports
  # the status operation.
  # (we start our server with -DSTATUS - just in case :-))
  #
  # Typically (but not necessarily) the status URL is /server-status
  #
  # For us to think status will work, we have to have the following things:
  #
  # - $WGET has to exist and be executable
  # - The server-status handler has to be mapped to some URL somewhere
  #
  # We assume that:
  #
  # - the "main" web server at $PORT will also support it if we can find it
  #	somewhere in the file
  # - it will be supported at the same URL as the one we find in the file
  #
  # If this doesn't work for you, then set STATUSURL at the top of the file
  #
  if
     [ "X$STATUSURL" = "X" ]
  then
    if
	have_binary $WGET
    then
      StatusURL=`FindLocationForHandler $1 server-status | tail -1`
      if
        [ "x$Listen" != "x" ]
      then
        echo $Listen | grep ':' >/dev/null ||  # Listen can be only port spec
          Listen="localhost:$Listen"
        STATUSURL="http://${Listen}$StatusURL"
        case $WGET in
          *wget*)	WGETOPTS="$WGETOPTS --bind-address=127.0.0.1";;
        esac
      else
        STATUSURL="${LOCALHOST}:${PORT}$StatusURL"
      fi
    fi
  fi
  test "$PidFile"
}

#
# return TRUE if a process with given PID is running
#
ProcessRunning() {
    ApachePID=$1
    # Use /proc if it looks like it's here...
    if
      [ -d /proc -a -d /proc/1 ]
    then
       [ -d /proc/$ApachePID ]
    else
      #  This assumes we're running as root...
      kill -0 "$ApachePID" >/dev/null 2>&1
    fi
}


silent_status() {
  if
    [ -f $PidFile  ] 
  then
    ProcessRunning `cat $PidFile`
  else
    : No pid file
    false
  fi
}

start_apache() {
  if
    silent_status
  then
    ocf_log info "$CMD already running (pid $ApachePID)"
    return $OCF_SUCCESS
  fi
  ocf_run $HTTPD $HTTPDOPTS $OPTIONS -f $CONFIGFILE
  tries=0
  while :  # wait until the user set timeout
  do
    monitor_apache
	ec=$?
	if [ $ec -eq $OCF_NOT_RUNNING ]
	then
		tries=`expr $tries + 1`
		ocf_log info "waiting for apache $CONFIGFILE to come up"
		sleep 1
	else
		break
	fi
  done
	return $ec
}

stop_apache() {
  if
    silent_status
  then
    if
      kill $ApachePID
    then
      tries=0
      while
        ProcessRunning $ApachePID &&
        [ $tries -lt 10 ]
      do
        sleep 1
        kill $ApachePID >/dev/null 2>&1
        ocf_log info "Killing apache PID $ApachePID"
        tries=`expr $tries + 1`
      done
    else
      ocf_log warn "Killing apache PID $ApachePID FAILED."
    fi
    if
      ProcessRunning $ApachePID
    then
      ocf_log info "$CMD still running ($ApachePID)."
      false
    else
      ocf_log info "$CMD stopped."
    fi
  else
    ocf_log info "$CMD is not running."
  fi

  for sig in SIGTERM SIGHUP SIGKILL ; do
    if pgrep -f $HTTPD.*$CONFIGFILE >/dev/null 2>&1 ; then
      pkill -$sig  -f $HTTPD.*$CONFIGFILE >/dev/null 2>&1
      ocf_log info "apache children were signalled ($sig)"
      sleep 1
    else
      break
    fi
  done
}

status_apache() {
  silent_status
  rc=$?
  if
    [ $rc -eq 0 ]
  then
    ocf_log info "$CMD is running (pid $ApachePID)."
    return $OCF_SUCCESS
  else
    ocf_log info "$CMD is stopped."
    return $OCF_NOT_RUNNING
  fi
}

monitor_apache() {
  if 
	! have_binary $WGET
  then
	ocf_log err "Monitoring not supported by $OCF_RESOURCE_INSTANCE"
	ocf_log info "Please make sure that wget is available"
	return $OCF_ERR_CONFIGURED

  elif [ -z "$STATUSURL" ]; then
	ocf_log err "Monitoring not supported by $CONFIGFILE"
	ocf_log info "Please set the statusurl parameter"
	return $OCF_ERR_CONFIGURED
  fi

  if
    silent_status
  then
    ocf_run sh -c "$WGET $WGETOPTS $STATUSURL | tr '\012' ' ' | grep -Ei \"$TESTREGEX\" >/dev/null"
  else
    ocf_log info "$CMD not running"
    return $OCF_NOT_RUNNING
  fi
}

metadata_apache(){
	cat <<END
<?xml version="1.0"?>
<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
<resource-agent name="apache">
<version>1.0</version>

<longdesc lang="en">
This is the resource agent for the
Apache web server.
Thie resource agent operates both version 1.x and version 2.x Apache
servers.
See also http://httpd.apache.org/
</longdesc>
<shortdesc lang="en">Apache web server</shortdesc>

<parameters>
<parameter name="configfile" required="1" unique="1">
<longdesc lang="en">
The full pathname of the Apache configuration file.
This file is parsed to provide defaults for various other
resource agent parameters.
</longdesc>
<shortdesc lang="en">configuration file path</shortdesc>
<content type="string" default="/etc/apache2/httpd.conf" />
</parameter>

<parameter name="httpd">
<longdesc lang="en">
The full pathname of the httpd binary (optional).
</longdesc>
<shortdesc lang="en">httpd binary path</shortdesc>
<content type="string" default="/usr/sbin/httpd" />
</parameter>

<parameter name="port" >
<longdesc lang="en">
A port number that we can probe for status information
using the statusurl.
This will default to the port number found in the
configuration file, or 80, if none can be found
in the configuration file.

</longdesc>
<shortdesc lang="en">httpd port</shortdesc>
<content type="integer" />
</parameter>

<parameter name="statusurl">
<longdesc lang="en">
The URL of the apache status module.
If left unspecified, it will be inferred
from the apache configuration file.
</longdesc>
<shortdesc lang="en">url name</shortdesc>
<content type="string" />
</parameter>

<parameter name="options">
<longdesc lang="en">
Extra options to apply when starting apache. See man httpd(8).
</longdesc>
<shortdesc lang="en">command line options</shortdesc>
<content type="string" />
</parameter>

<parameter name="testregex">
<longdesc lang="en">
Regular expression to match in the output of statusurl. It
is case insensitive.
</longdesc>
<shortdesc lang="en">test regular expression</shortdesc>
<content type="string" />
</parameter>

</parameters>

<actions>
<action name="start"   timeout="90" />
<action name="stop"    timeout="100" />
<action name="status"  timeout="30" />
<action name="monitor" depth="0"  timeout="20" interval="10" start-delay="1m" />
<action name="meta-data"  timeout="5" />
<action name="validate-all"  timeout="5" />
</actions>
</resource-agent>
END

	exit $OCF_SUCCESS
}

validate_all_apache() {

  if CheckPort $PORT; then
# We are sure to succeed here, since we forced $PORT to be valid in GetParams()
	: OK
  else
	ocf_log err "Port number $PORT is invalid!"
	exit $OCF_ERR_ARGS
  fi

  if [ -z $STATUSURL ]; then
	: OK to be empty
  else
	case $STATUSURL in
	    http://*/*) ;;
	    *) 
	    ocf_log err "Invalid STATUSURL $STATUSURL"
	    exit $OCF_ERR_ARGS ;;
	esac
  fi
  if [ ! -x $HTTPD ]; then
	ocf_log err "HTTPD $HTTPD not found or is not an executable!"
	exit $OCF_ERR_ARGS
  fi
  if [ ! -f $CONFIGFILE ]; then
# We are sure to succeed here, since we have parsed $CONFIGFILE before getting here
	ocf_log err "Configuration file $CONFIGFILE not found!"
	exit $OCF_ERR_CONFIGURED
  fi


  return $OCF_SUCCESS
}

if
  [ $# -eq 1 ]
then
  COMMAND=$1
  HTTPD="$OCF_RESKEY_httpd"
  PORT="$OCF_RESKEY_port"
  STATUSURL="$OCF_RESKEY_statusurl"
  CONFIGFILE="$OCF_RESKEY_configfile"
  OPTIONS="$OCF_RESKEY_options"
  TESTREGEX=${OCF_RESKEY_testregex:-'</ *body *>[[:space:]]*</ *html *>'}
else
  usage $OCF_ERR_ARGS
fi

LSB_STATUS_STOPPED=3
if
  [ "X$HTTPD" = X -o ! -f "$HTTPD" -o ! -x "$HTTPD" ]
then
  case $0 in
    *IBM*)	HTTPD=$IBMHTTPD
		DefaultConfig=$DEFAULT_IBMCONFIG;;
    *)	
	HTTPD=
	for h in $HTTPDLIST
	do
	  if
	    [ -f $h -a -x $h ]
	  then
	    HTTPD=$h
	    break
	  fi
	done
# It is possible that we still do not have a valid httpd at this stage
	if
          [ -z "$HTTPD" ]
	then
	  case $COMMAND in
	    stop)	exit	$OCF_SUCCESS;;
	    monitor)	exit	$OCF_NOT_RUNNING;;
            status)	exit  $LSB_STATUS_STOPPED;;
  	    meta-data)	metadata_apache;;
	  esac
	  ocf_log err "No valid httpd found! Please revise your <HTTPDLIST> item"
          exit $OCF_ERR_INSTALLED
	fi
# Let the user know that the $HTTPD used is not the one (s)he specified via $OCF_RESKEY_httpd
        if
          [ "X$OCF_RESKEY_httpd" != X ]
        then
	  ocf_log info "Using $HTTPD as HTTPD"
        fi
	DefaultConfig=$DEFAULT_NORMCONFIG;;
  esac
fi
httpd_basename=`basename $HTTPD`
case $httpd_basename in
  *-*)	httpd_basename=`echo "$httpd_basename" | sed -e 's%\-.*%%'`;;
esac

case "$CONFIGFILE" in
  "") CONFIGFILE=$DefaultConfig;;
  *)		;;
esac

if
  [ ! -f "$CONFIGFILE" ]
then
  case $COMMAND in
    stop)	ocf_log warn "$CONFIGFILE not found - apache considered stopped"
    		exit $OCF_SUCCESS;;
    monitor)	exit $OCF_NOT_RUNNING;;
    status)	exit $LSB_STATUS_STOPPED;;
  esac
fi

if
  [ "X$COMMAND" = Xmeta-data ] || GetParams $CONFIGFILE
then
  : OK
else
  ocf_log err "Cannot parse config file [$CONFIGFILE]"
  exit $OCF_ERR_CONFIGURED
fi

case $COMMAND in
  start)	start_apache;;
  stop)		stop_apache;;
  status)	status_apache;;
  monitor)	monitor_apache;;
  meta-data)	metadata_apache;;
  validate-all)	validate_all_apache;;
  *)		usage $OCF_ERR_UNIMPLEMENTED;;
esac
