#!/bin/sh
#
#	High-Availability Apache/IBMhttp control script
# 
# apache (aka IBMhttpd)
#
# Description:	starts/stops apache web servers.
#
# Author:	Alan Robertson
#		Sun Jiang Dong
#
# Support:	users@clusterlabs.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_RESKEY_client
#  OCF_RESKEY_testurl
#  OCF_RESKEY_testregex10
#  OCF_RESKEY_testconffile
#  OCF_RESKEY_testname
#  OCF_RESKEY_envfiles


: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs
. ${OCF_FUNCTIONS_DIR}/apache-conf.sh
. ${OCF_FUNCTIONS_DIR}/http-mon.sh
HA_VARRUNDIR=${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

LOCALHOST="http://localhost"
HTTPDOPTS="-DSTATUS"
DEFAULT_IBMCONFIG=/opt/IBMHTTPServer/conf/httpd.conf
DEFAULT_SUSECONFIG="/etc/apache2/httpd.conf"
DEFAULT_RHELCONFIG="/etc/httpd/conf/httpd.conf"
DEFAULT_DEBIANCONFIG="/etc/apache2/apache2.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 either $DEFAULT_RHELCONFIG or $DEFAULT_SUSECONFIG depending
#	on which is detected.
usage() {
cat <<-END
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 either curl or wget for this to work.

	meta-data	show meta data message

	validate-all	validate the instance parameters
END
}

get_pid() {
	if [ -f $PidFile ]; then
		cat $PidFile
	else
		false
	fi
}
#
# return TRUE if a process with given PID is running
#
ProcessRunning() {
	local pid=$1

	# Use /proc if it looks like it's here...
	if [ -d /proc -a -d /proc/1 ]; then
		[ -d /proc/$pid ]
	else
		# This assumes we're running as root...
		kill -s 0 "$pid" >/dev/null 2>&1
	fi
}
silent_status() {
	local pid
	local rc=$OCF_ERR_GENERIC
	local retries=0

	# Set a retry when apache's Graceful restart is applied and the pid file can not be acquired.
	if [ "$__OCF_ACTION" = "monitor" ] && ! ocf_is_probe; then
		retries=5
	fi

	while true; do
		pid=`get_pid`
		if [ -n "$pid" ]; then
			ProcessRunning $pid
			rc=$?
			break
		fi

		: No pid file
		if [ $retries -le 0 ]; then
			break
		fi

		sleep 1
		retries=`expr $retries - 1`
	done

	return $rc
}

# May be useful to add other distros in future
validate_default_config() {
	if [ -e /etc/SuSE-release ]; then
		validate_default_suse_config
	elif [ -e /etc/debian_version ]; then
		validate_default_debian_config
	else
		return 0
	fi
}

# When using the default /etc/apache2/httpd.conf on SUSE, the file
# /etc/apache2/sysconfig.d/include.conf is required to be present,
# but this is only generated if you run the apache init script
# (with contents derived from /etc/sysconfig/apache2).  So, here,
# if we're using the default system config file and it requires
# that include, we run "/etc/init.d/apache2 configtest" to ensure
# the relevant config is generated and valid.  We're also taking
# this opportunity to enable mod_status if it's not present.
validate_default_suse_config() {
	if [ "$CONFIGFILE" = "$DEFAULT_SUSECONFIG" ] && \
		grep -Eq '^Include[[:space:]]+/etc/apache2/sysconfig.d/include.conf' "$CONFIGFILE"
	then
		[ -x "/usr/sbin/a2enmod" ] && ocf_run -q /usr/sbin/a2enmod status
		# init script style, for crusty old SUSE
		if [ -e "/etc/init.d/apache2" ]; then
			ocf_run -q /etc/init.d/apache2 configtest || return 1
		# systemd style, for shiny new SUSE
		elif [ -e "/usr/sbin/start_apache2" ]; then
			ocf_run -q /usr/sbin/start_apache2 -t || return 1
		fi
	fi
	return 0
}

# Debian's Default configuration uses a lock directory /var/lock/apache2
# which is only generated using the lsb init script issues configtest. To
# ensure these default directories are present it's useful to run a configtest
# prior to the resource startup which will create the needed directories
#
# To support multiple apache instances the debian scripts and configs
# obey apache2/envvars. (copy /etc/apache2 -> /etc/apache2-instance)
# adjust (SUFFIX) envvars and set OCF_RESKEY_envfiles
validate_default_debian_config() {
	if find /etc/apache2* -name apache2.conf | grep -q "$CONFIGFILE"
	then
		export APACHE_CONFDIR=$(dirname $CONFIGFILE)
		[ -x "/usr/sbin/a2enmod" ] && ocf_run -q /usr/sbin/a2enmod status
		ocf_run -q /usr/sbin/apache2ctl configtest || return 1
	fi
	return 0
}

apache_start() {
	if
		silent_status
	then
		ocf_log info "$CMD already running (pid `get_pid`)"
		return $OCF_SUCCESS
	fi

	validate_default_config || return $OCF_ERR_CONFIGURED

	if [ -z $PIDFILE_DIRECTIVE ]; then
		ocf_run $HTTPD $HTTPDOPTS $OPTIONS -f $CONFIGFILE
	else
		ocf_run $HTTPD $HTTPDOPTS $OPTIONS -f $CONFIGFILE -c "PidFile $PidFile"
	fi

	tries=0
	while : # wait until the user set timeout
	do
		apache_monitor
		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

	if [ $ec -ne 0 ] && silent_status; then
		apache_stop
	fi
	return $ec
}

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

graceful_stop()
{
	local tries=10
	local pid=$1

	# Try graceful stop for half timeout period if timeout period is present
	if [ -n "$OCF_RESKEY_CRM_meta_timeout" ]; then
		tries=$((($OCF_RESKEY_CRM_meta_timeout/1000) / 2))
	fi

	ocf_log info "Attempting graceful stop of apache PID $pid"
	kill -WINCH $pid >/dev/null
	while
		ProcessRunning $pid &&
		[ $tries -gt 0 ]
	do
		sleep 1
		tries=`expr $tries - 1`
	done

	if [ $tries -eq 0 ]; then
		# graceful stop didn't work, process still up.
		return 1
	fi

	return 0
}

kill_stop()
{
	local tries=0
	local pid=$1

	ocf_log info "Killing apache PID $pid"
	if ProcessRunning $pid; then
		kill $pid >/dev/null
		while
			[ $tries -lt 10 ]
		do
			if ProcessRunning $pid; then
				tries=`expr $tries + 1`
				sleep 1
			else
				break
			fi
		done
	fi
}

apache_stop() {
	local ret=$OCF_SUCCESS
	local pid

	if ! silent_status; then
		ocf_log info "$CMD is not running."
		signal_children
		return $ret
	fi

	pid=`get_pid`
	graceful_stop $pid
	if [ $? -ne 0 ]; then
		kill_stop $pid
	fi

	signal_children

	if ProcessRunning $pid; then
		ocf_exit_reason "$CMD still running ($pid). Killing pid failed."
		ret=$OCF_ERR_GENERIC
	fi

	if [ $ret -eq 0 ]; then
		ocf_log info "$CMD stopped."
	fi

	return $ret
}

apache_monitor_10() {
	if [ -f "$TESTCONFFILE" ] && [ -r "$TESTCONFFILE" ]; then
		readtestconf < $TESTCONFFILE
	else
		test_url="$TESTURL"
		test_regex="$TESTREGEX10"
	fi

	whattorun=`gethttpclient`
	fixtesturl
	is_testconf_sane ||
		return $OCF_ERR_CONFIGURED

	if $whattorun "$test_url" | grep -Ei "$test_regex" > /dev/null
	then
		return $OCF_SUCCESS
	else
		if ! ocf_is_probe; then
			ocf_exit_reason "Failed to access httpd status page."
		fi
		return $OCF_ERR_GENERIC
	fi
}

# If the user has not provided any basic monitoring 
# information, allow the agent to verify the server is
# healthy and capable of processing requests by requesting
# the http header of website's index 
attempt_index_monitor_request() {
	local indexpage=""
	
	if [ -n "$OCF_RESKEY_testregex" ]; then
		return 1;
	fi
	if [ -n "$OCF_RESKEY_testregex10" ]; then
		return 1;
	fi
	if [ -n "$OCF_RESKEY_testurl" ]; then
		return 1;
	fi
	if [ -n "$OCF_RESKEY_statusurl" ]; then
		return 1;
	fi
	if [ -n "$OCF_RESKEY_testconffile" ]; then
		return 1;
	fi

	indexpage=$(buildlocalurl)

	request_url_header $indexpage
	if [ $? -ne 0 ]; then
		return $OCF_ERR_GENERIC
	fi
	ocf_log debug "Successfully retrieved http header at $indexpage"
	return 0
}

apache_monitor_basic() {
	if ${ourhttpclient}_func "$STATUSURL" | grep -Ei "$TESTREGEX" > /dev/null
	then
		return $OCF_SUCCESS
	fi

	attempt_index_monitor_request
	if [ $? -eq 0 ]; then
		return $OCF_SUCCESS
	fi

	if ! ocf_is_probe; then
		ocf_exit_reason "Failed to access httpd status page."
	fi
	return $OCF_ERR_GENERIC
}
apache_monitor() {
	silent_status
	if [ $? -ne 0 ]; then
		ocf_log info "$CMD not running"
		return $OCF_NOT_RUNNING
	fi

	ourhttpclient=`findhttpclient`  # we'll need one
	if [ -z "$ourhttpclient" ]; then
		ocf_exit_reason "could not find a http client; make sure that either wget or curl is available"
		return $OCF_ERR_INSTALLED
	fi

	case `ocf_check_level 10` in
		0) apache_monitor_basic;;
		10) apache_monitor_10;;
	esac
}

detect_default_config()
{
	if [ -f $DEFAULT_SUSECONFIG ]; then
		echo $DEFAULT_SUSECONFIG
	elif [ -f $DEFAULT_DEBIANCONFIG ]; then
		echo $DEFAULT_DEBIANCONFIG
	else
		echo $DEFAULT_RHELCONFIG
	fi
}


apache_meta_data(){
	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.
This resource agent operates both version 1.x and version 2.x Apache
servers.

The start operation ends with a loop in which monitor is
repeatedly called to make sure that the server started and that
it is operational. Hence, if the monitor operation does not
succeed within the start operation timeout, the apache resource
will end with an error status.

The monitor operation by default loads the server status page
which depends on the mod_status module and the corresponding
configuration file (usually /etc/apache2/mod_status.conf).
Make sure that the server status page works and that the access
is allowed *only* from localhost (address 127.0.0.1).
See the statusurl and testregex attributes for more details.

See also http://httpd.apache.org/
</longdesc>
<shortdesc lang="en">Manages an Apache Web server instance</shortdesc>

<parameters>
<parameter name="configfile" required="0" 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="$(detect_default_config)" />
</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 to monitor (the apache server status page by default).
If left unspecified, it will be inferred from
the apache configuration file.

If you set this, make sure that it succeeds *only* from the
localhost (127.0.0.1). Otherwise, it may happen that the cluster
complains about the resource being active on multiple nodes.
</longdesc>
<shortdesc lang="en">url name</shortdesc>
<content type="string" />
</parameter>

<parameter name="testregex">
<longdesc lang="en">
Regular expression to match in the output of statusurl.
Case insensitive.
</longdesc>
<shortdesc lang="en">monitor regular expression</shortdesc>
<content type="string" default="exists, but impossible to show in a human readable format (try grep testregex)"/>
</parameter>

<parameter name="client">
<longdesc lang="en">
Client to use to query to Apache. If not specified, the RA will
try to find one on the system. Currently, wget and curl are
supported. For example, you can set this parameter to "curl" if
you prefer that to wget.
</longdesc>
<shortdesc lang="en">http client</shortdesc>
<content type="string" default=""/>
</parameter>

<parameter name="testurl">
<longdesc lang="en">
URL to test. If it does not start with "http", then it's
considered to be relative to the Listen address.
</longdesc>
<shortdesc lang="en">test url</shortdesc>
<content type="string" />
</parameter>

<parameter name="testregex10">
<longdesc lang="en">
Regular expression to match in the output of testurl.
Case insensitive.
</longdesc>
<shortdesc lang="en">extended monitor regular expression</shortdesc>
<content type="string" />
</parameter>

<parameter name="testconffile">
<longdesc lang="en">
A file which contains test configuration. Could be useful if
you have to check more than one web application or in case sensitive
info should be passed as arguments (passwords). Furthermore,
using a config file is the only way to specify certain
parameters.

Please see README.webapps for examples and file description.
</longdesc>
<shortdesc lang="en">test configuration file</shortdesc>
<content type="string" />
</parameter>

<parameter name="testname">
<longdesc lang="en">
Name of the test within the test configuration file.
</longdesc>
<shortdesc lang="en">test 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="envfiles">
<longdesc lang="en">
Files (one or more) which contain extra environment variables.
If you want to prevent script from reading the default file, set
this parameter to empty string.
</longdesc>
<shortdesc lang="en">environment settings files</shortdesc>
<content type="string" default="/etc/apache2/envvars"/>
</parameter>

<parameter name="use_ipv6">
<longdesc lang="en">
We will try to detect if the URL (for monitor) is IPv6, but if
that doesn't work set this to true to enforce IPv6.
</longdesc>
<shortdesc lang="en">use ipv6 with http clients</shortdesc>
<content type="boolean" default="false"/>
</parameter>

</parameters>

<actions>
<action name="start"   timeout="40s" />
<action name="stop"    timeout="60s" />
<action name="status"  timeout="30s" />
<action name="monitor" depth="0"  timeout="20s" interval="10s" />
<action name="meta-data"  timeout="5s" />
<action name="validate-all"  timeout="5s" />
</actions>
</resource-agent>
END
	return $OCF_SUCCESS
}

apache_validate_all() {
	if [ -z "$HTTPD" ]; then
		ocf_exit_reason "apache httpd program not found"
		return $OCF_ERR_INSTALLED
	fi
	if [ ! -x "$HTTPD" ]; then
		ocf_exit_reason "HTTPD $HTTPD not found or is not an executable!"
		return $OCF_ERR_INSTALLED
	fi
	if [ ! -f $CONFIGFILE ]; then
		ocf_exit_reason "Configuration file $CONFIGFILE not found!"
		return $OCF_ERR_INSTALLED
	fi

	# validate testconffile/testurl before apache_monitor_10()
	if [ -n "$TESTCONFFILE" ]; then
		if [ ! -f "$TESTCONFFILE" ] || [ ! -r "$TESTCONFFILE" ]; then
			ocf_exit_reason "Configuration file $TESTCONFFILE not found, or not readable."
			return $OCF_ERR_INSTALLED
		fi
	else
		if [ -n "$TESTURL" ]; then
			# remove leading or trailing spaces/tabs
			local temp=$(printf "$TESTURL" | sed -e 's/^[ \t]*//g' -e 's/[ \t]*$//g')

			if [ -z "$temp" ]; then
				ocf_exit_reason "testurl: \"$TESTURL\" seems to be an empty string?"
				return $OCF_ERR_CONFIGURED
			fi
		fi

		# FIXME: validate TESTREGEX10 will be needed if empty regex is not allow.
	fi

	ocf_mkstatedir root 755 `dirname $PidFile` || return $OCF_ERR_INSTALLED
	return $OCF_SUCCESS
}

find_httpd_prog() {
	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

			# 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 -a "X$HTTPD" != X ]; then
				ocf_log info "Using $HTTPD as HTTPD"
			fi
			DefaultConfig=$(detect_default_config)
			;;
	esac
}

apache_getconfig() {
	# these variables are global
	HTTPD="$OCF_RESKEY_httpd"
	PORT="$OCF_RESKEY_port"
	STATUSURL="$OCF_RESKEY_statusurl"
	CONFIGFILE="$OCF_RESKEY_configfile"
	OPTIONS="$OCF_RESKEY_options"
	CLIENT=${OCF_RESKEY_client}
	TESTREGEX=${OCF_RESKEY_testregex:-'</ *html *>'}
	TESTURL="$OCF_RESKEY_testurl"
	TESTREGEX10=${OCF_RESKEY_testregex10}
	TESTCONFFILE="$OCF_RESKEY_testconffile"
	TESTNAME="$OCF_RESKEY_testname"
	: ${OCF_RESKEY_envfiles="/etc/apache2/envvars"}
	source_envfiles $OCF_RESKEY_envfiles

	if [ "X$HTTPD" = X -o ! -f "$HTTPD" -o ! -x "$HTTPD" ]; then
		find_httpd_prog
	fi

	CONFIGFILE=${CONFIGFILE:-$DefaultConfig}
	if [ -n "$HTTPD" ]; then
		httpd_basename=`basename $HTTPD`
		case $httpd_basename in
			*-*)	httpd_basename=`echo "$httpd_basename" | sed -e 's%\-.*%%'`;;
		esac
	fi
	GetParams $CONFIGFILE
}

OCF_REQUIRED_PARAMS=""
OCF_REQUIRED_BINARIES=""
ocf_rarun $*
