solr/bin/functions.sh - lucene-solr - Git at Google

 # 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.
 #
 ###
 ### Shell script functions for Solr
 ###
 #
 ##### Setup
 DEFAULT_AGENT_HEAP=16M
 DEFAULT_AGENT_MAIN_ETC_DIR=/etc/solr
 DEFAULT_AGENT_PORT=58983
 DEFAULT_CLOUD_BUILD_ADDRESS=239.89.83.0
 DEFAULT_CLOUD_BUILD_PORT=8983
 DEFAULT_SOLR_HEAP=512M
 DEFAULT_SOLR_PORT=8983
 DEFAULT_X_WHICH=/usr/bin/which
 DEFAULT_ZK_CLIENT_PORT=2181
 DEFAULT_ZK_ELECTION_PORT=3888
 DEFAULT_ZK_LEADER_PORT=2888
 ##### End Setup
 #
 #----
 # DO NOT EDIT BELOW THIS LINE WITHOUT GUIDANCE
 #----

 if [ -z "${AGENT_HEAP}" ]; then
   AGENT_HEAP="${DEFAULT_AGENT_HEAP}"
 fi

 if [ -z "${AGENT_MAIN_ETC_DIR}" ]; then
   AGENT_MAIN_ETC_DIR="${DEFAULT_AGENT_MAIN_ETC_DIR}"
 fi

 if [ -z "${AGENT_PORT}" ]; then
   AGENT_PORT="${DEFAULT_AGENT_PORT}"
 fi

 if [ -z "${CLOUD_BUILD_ADDRESS}" ]; then
   CLOUD_BUILD_ADDRESS="${DEFAULT_CLOUD_BUILD_ADDRESS}"
 fi

 if [ -z "${CLOUD_BUILD_PORT}" ]; then
   CLOUD_BUILD_PORT="${DEFAULT_CLOUD_BUILD_PORT}"
 fi

 if [ -z "${SOLR_HEAP}" ]; then
   SOLR_HEAP="${DEFAULT_SOLR_HEAP}"
 fi

 if [ -z "${SOLR_PORT}" ]; then
   SOLR_PORT="${DEFAULT_SOLR_PORT}"
 fi

 if [ -z "${X_WHICH}" ]; then
   X_WHICH="${DEFAULT_X_WHICH}"
 fi

 if [ -z "${ZK_CLIENT_PORT}" ]; then
   ZK_CLIENT_PORT="${DEFAULT_ZK_CLIENT_PORT}"
 fi

 if [ -z "${ZK_ELECTION_PORT}" ]; then
   ZK_ELECTION_PORT="${DEFAULT_ZK_ELECTION_PORT}"
 fi

 if [ -z "${ZK_LEADER_PORT}" ]; then
   ZK_LEADER_PORT="${DEFAULT_ZK_LEADER_PORT}"
 fi

 # Write a message to stderr indicating that a command is required.
 # If no command is provided to this function, use a generic message.
 # Exit the script after writing the message.
 exit_err_msg_required_command() {
   REQ_CMD="$1"
   if [ -z "${REQ_CMD}" ]; then
     echo >&2 "A command required to run this script is missing."
   else
     echo >&2 "The ${REQ_CMD} command is required to run this script."
   fi
   err_msg_contact_community
   exit 1
 }

 # Write a message asking the user to contact the Solr community if they
 # feel that there's a problem.
 err_msg_contact_community() {
   echo >&2 "---"
   echo >&2 "If you feel this is in error, please mention the problem"
   echo >&2 "to the Solr community on the mailing list or IRC channel."
   echo >&2 "http://lucene.apache.org/solr/community.html#mailing-lists-irc"
 }

 # Locate directories based based on a script directory passed in as the first
 # argument and set environment variables.  The current working directory will
 # be set to the parent of that directory and assigned to SOLR_TIP.
 find_dirs_and_change_cwd() {
   MYDIR="$1"
   cd ${MYDIR}
   cd ..
   SOLR_TIP=`pwd`
   LOCAL_ETC_DIR=${SOLR_TIP}/etc
   SOLR_LIB_DIR=${SOLR_TIP}/lib
   SOLR_TMP_DIR=${SOLR_TIP}/tmp
   SOLR_RUN_DIR=${SOLR_TIP}/run
 }

 # Find required system executables or shell builtin commands and set
 # variables like X_TEMPFILE so the script has a better chance of running
 # on systems where things are installed outside of LSB locations.
 find_system_programs_or_exit() {
   # Make sure the which command is available.
   if [ ! -x "${X_WHICH}" ]; then
     echo >&2 "The command ${X_WHICH} is not found or not executable."
     exit_err_msg_required_command "${X_WHICH}"
   fi

   # Check for the existence of other commands we need.
   locate_command_or_exit tempfile X_TEMPFILE 1
   locate_command_or_exit find X_FIND 1
   locate_command_or_exit xargs X_XARGS 1
   # We look for lsof and netstat, but do not exit
   # if they are not found.
   locate_command_or_exit lsof X_LSOF 0
   locate_command_or_exit netstat X_NETSTAT 0
   # If NEITHER lsof or netstat is found, log a warning message.
   if [-z "${X_LSOF}" ] && [ -z "${X_NETSTAT}" ]; then
     echo >&2 "Neither lsof or netstat found.  Will not be able to check for"
     echo >&2 "programs already listening on relevant ports."
   fi
 }

 # Check whether a program exists as a builtin or an executable.  Will not
 # validate a command that is a function or an alias.  Assign a dynamic
 # variable to the bare program name or an executable file path as required
 # if found, exit the script if not.  The first argument is the bare command,
 # the second argument is the variable that will be assigned with the correct
 # command or executable.  The third argument is an exit flag -- a numeric
 # boolean value (usually 0 or 1) indicating whether or not a missing program
 # will cause a script exit.  A missing program will result in an error message
 # whether an exit is forced or not.  The first two arguments are required.
 # The exit flag will default to 1 if not present.  If the variable mentioned
 # as the second argument is already defined, then the value of that variable
 # will override the first argument to this script and tested to make sure it
 # is a valid command.  This allows somebody to define variables like X_TEMPFILE
 # in advance to override the automatic detection, while making sure that the
 # explicitly set value is actually a good command.
 locate_command_or_exit() {
   PRGNAME=$1
   shift
   PRGVAR=$1
   shift
   EXITFLAG=$1

   if [ -z "${PRGNAME}" ] || [ -z "${PRGVAR}" ]; then
     echo >&2 "locate_command_or_exit routine missing required arguments."
     echo >&2 "Aborting script."
     err_msg_contact_community
     exit 1
   fi

   if [ -z "${EXITFLAG}" ]; then
     EXITFLAG=1;
   fi

   BADPROG=0
   if [ -n "${!PRGVAR}" ]; then
     echo >&2 "The ${PRGNAME} command has been predefined as ${!PRGVAR}."
     PRGNAME="${!PRGVAR}"
   fi

   CMD_TYPE=`type -t ${PRGNAME}`
   if [ "${CMD_TYPE}" == "builtin" ]; then
     eval ${PRGVAR}="\${PRGNAME}"
   elif [ "${CMD_TYPE}" == "file" ]; then
     XPATH=`"${X_WHICH}" "${PRGNAME}"`
     RET=$?
     if [ $RET -eq 0 ]; then
       if [ -x "${XPATH}" ]; then
         eval ${PRGVAR}="\${XPATH}"
       else
         BADPROG=1
       fi
     else
       BADPROG=1
     fi
   else
     BADPROG=1
   fi

   if [ ${BADPROG} -ne 0 ]; then
     echo >&2 "The ${PRGNAME} command is not found or not executable."
     echo >&2 "The ${PRGVAR} env variable can explicitly set its location."
     if [ ${EXITFLAG} -ne 0 ]; then
       exit_err_msg_required_command "${PRGNAME}"
     fi
   fi
   return 0
 }

 # Find Java and set the JAVA variable.
 # Exit script if unable to locate a java executable.
 find_java_or_exit() {
   JAVA=
   if [ -n "$SOLR_JAVA_HOME" ]; then
     echo >&2 "SOLR_JAVA_HOME found, using it as JAVA_HOME."
     JAVA_HOME="$SOLR_JAVA_HOME"
   fi

   if [ -n "$JAVA_HOME" ]; then
     for java in "${JAVA_HOME}/bin/amd64/java" "${JAVA_HOME}/bin/java"; do
       if [ -x "$java" ]; then
         JAVA="$java"
         break
       fi
     done
     if [ -z "$JAVA" ]; then
       echo >&2 "The currently defined JAVA_HOME (${JAVA_HOME}) refers"
       echo >&2 "to a location where Java could not be found.  Aborting."
       echo >&2 "Either fix the variable or remove it from the environment"
       echo >&2 "so that the system PATH will be searched."
       err_msg_contact_community
       exit 1
     fi
   else
     X_JAVA=`"${X_WHICH}" java`
     if [ -x "${X_JAVA}" ]; then
       JAVA=${X_JAVA}
     else
       echo >&2 "Unable to locate a java executable."
       err_msg_contact_community
       exit 1
     fi
   fi
   return 0
 }

 # Start the agent.  Will pass all parameters to the startup.
 # The first parameter is the properties file to use.
 agent_start() {
   start_agent_program $@ start
 }

 # Start the agent program with a commandline parameter that tells it
 # to examine its config and the system, and use what it finds to create
 # a bunch of environment variables.  The agent will output the commands
 # for the variables to stdout.
 agent_get_env() {
   start_agent_program get_env
   return $?
 }

 # Start the agent with arguments sent to this function.
 # Removes all options (things like -D), leaving only commands for the agent.
 # Will set a SOLR_AGENT_PROPERTIES sysprop with that variable value.
 start_agent_program() {
   CP_JARS=`get_jars_for_classpath ${SOLR_TIP}/lib/log ${SOLR_TIP}/lib/solrj`

   OPTIND=1
   while getopts ":D:" opt; do
     case ${opt} in
       D)
         # Do nothing.  This will remove the option.  May not need this case.
         ;;
       *)
         # Do nothing.  This will remove the option.
         ;;
     esac
   done
   shift $((OPTIND -1))

   $JAVA -Xmx${AGENT_HEAP} -cp ${CP_JARS} -DSOLR_AGENT_PROPERTIES="${SOLR_AGENT_PROPERTIES}" -jar lib/agent.jar $@
   return $?
 }

 # Given a list of path locations, recursively find all the jars and write a
 # classpath string to stdout.
 get_jars_for_classpath() {
   get_files_for_classpath jar $@
 }

 # Given an extension and a list of of path locations, recursively find all
 # the files with that extension and write a classpath string to stdout.  To
 # include all files, pass an equal sign in as the extension.
 get_files_for_classpath() {
   CP_EXTENSION=$1
   shift

   if [ "${CP_EXTENSION}" == "=" ]; then
     CP_FILESPEC="*"
   else
     CP_FILESPEC="*.${CP_EXTENSION}"
   fi

   DETECTED_CLASSPATH=
   ADDED_FIRST_CP_ENTRY=
   KEEP_RUNNING=true
   while [ -n "${KEEP_RUNNING}" ]; do
     CHECKDIR=$1
     shift
     if [ -n "${CHECKDIR}" ]; then
       if [ -d "${CHECKDIR}" ]; then
         while IFS= read -r -d '' line; do
           add_to_detected_classpath "$line"
         done < <(${X_FIND} ${CHECKDIR} -type f -name "${CP_FILESPEC}" -print0)
       fi
     else
       KEEP_RUNNING=
     fi
   done
   echo "$DETECTED_CLASSPATH"
 }

 add_to_detected_classpath() {
   CP_ENTRY="$1"
   if [ -n "${ADDED_FIRST_CP_ENTRY}" ]; then
     # If the first entry in the classpath has been added
     # we add a colon before the entry as a separator.
     CP_ENTRY=":${CP_ENTRY}"
   fi
   # Set the value to indicate the first entry has been added.
   ADDED_FIRST_CP_ENTRY=true
   DETECTED_CLASSPATH="${DETECTED_CLASSPATH}${CP_ENTRY}"
 }

 # Locate the agent properties file based on available information.
 # The SOLR_AGENT_PROPERTIES variable may be empty after this runs,
 # but only if this is a non-service install.
 find_agent_properties_or_exit() {
   # First, if service name is not set, try to figure out a service name.
   # When no service name set and only one service is installed, we assume
   # that service.  If multiple services installed and no name is set, the
   # script will abort.
   if [ -z "${SOLR_SERVICE_NAME}" ]; then
     SOLR_SERVICES_CONFIG=${LOCAL_ETC_DIR}/services.conf
     declare -a SERVICES
     if [ -r "${SOLR_SERVICES_CONFIG}" ]; then
       readarray -t SERVICES < ${SOLR_SERVICES_CONFIG}
     fi
     if [ ${#SERVICES[@]} -gt 0 ]; then
       if [ ${#SERVICES[@]} -eq 1 ]; then
         SOLR_SERVICE_NAME=${SERVICES[0]}
       else
         echo >&2 "Multiple services detected in ${SOLR_SERVICES_CONFIG}"
         echo >&2 "SOLR_SERVICE_NAME must be defined to proceed."
         err_msg_contact_community
         exit 1
       fi
     fi
   fi

   # If we reach here, then we have either settled on one service name or
   # there are no services.
   if [ -n "${SOLR_SERVICE_NAME}" ]; then
     echo >&2 "Solr service name ${SOLR_SERVICE_NAME} detected."
     SOLR_AGENT_PROPERTIES=${MAIN_ETC_DIR}/${SOLR_SERVICE_NAME}/solr-agent.properties
   else
     SOLR_AGENT_PROPERTIES=${LOCAL_ETC_DIR}/solr-agent.properties
   fi

   # When running as a service, the agent properties file must exist. When the
   # properties file does not exist, decide whether to exit or use defaults.
   if [ ! -r "${SOLR_AGENT_PROPERTIES}" ]; then
     if [ -n "${SOLR_SERVICE_NAME}" ]; then
       echo >&2 "The ${SOLR_AGENT_PROPERTIES} file is not found or not readable."
       echo >&2 "Service installs must have an agent properties file."
       err_msg_contact_community
       exit 1
     else
       echo >&2 "The ${SOLR_AGENT_PROPERTIES} file is not found or not readable."
       echo >&2 "Proceeding with defaults for a non-service install."
       SOLR_AGENT_PROPERTIES=
     fi
     # TODO: Service recommendation might need to move.
     if [ -z "${SOLR_SERVICE_NAME}" ]; then
       recommend_service
     fi
   fi
 }

 recommend_service() {
   echo >&2 "Non-service install detected."
   echo >&2 "Installing Solr as a service is strongly recommended."
   echo >&2 "https://lucene.apache.org/solr/guide/taking-solr-to-production.html"
 }

 # Determine whether or not the configured version of Java supports the
 # ExitOnOutOfMemoryError flag.  Sets JAVA_OOM_EXIT_SUPPORTED with a numeric
 # boolean value and returns the exit code from the attempt to run Java with
 # that option.
 check_oom_exit_supported() {
   $JAVA -Xmx1M -XX:+ExitOnOutOfMemoryError -version > /dev/null 2> /dev/null
   RET=$?
   if [ ${RET} -eq 0 ]; then
     JAVA_OOM_EXIT_SUPPORTED=1
   else
     JAVA_OOM_EXIT_SUPPORTED=0
   fi
   return ${RET}
 }

 # If the BASH_VERSION variable is not set, it is a reasonable indication
 # that the shell we are running in is not bash.  If that situation is
 # detected, exit.
 exit_if_no_bash() {
   if [ -z "${BASH_VERSION}" ]; then
     echo >&2 "This script must be run by the bash shell."
     err_msg_contact_community
     exit 1
   fi
 }

 # Exit script if the bash version is too old.  Require version 4.
 # The first release of bash 4 was in 2009.
 exit_if_bash_too_old() {
   if [ -n "${BASH_VERSINFO[*]}" ]; then
     if [ "${BASH_VERSINFO[0]}" -lt 4 ]; then
       echo >&2 "Detected bash version is ${BASH_VERSION}."
       echo >&2 "Script needs at least version 4."
       err_msg_contact_community
       exit 1
     fi
   else
     echo >&2 "There was a problem detecting bash version."
     echo >&2 "Aborting because compatibility cannot be detected."
     err_msg_contact_community
     exit 1
   fi
 }
	# 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.
	#
	###
	### Shell script functions for Solr
	###
	#
	##### Setup
	DEFAULT_AGENT_HEAP=16M
	DEFAULT_AGENT_MAIN_ETC_DIR=/etc/solr
	DEFAULT_AGENT_PORT=58983
	DEFAULT_CLOUD_BUILD_ADDRESS=239.89.83.0
	DEFAULT_CLOUD_BUILD_PORT=8983
	DEFAULT_SOLR_HEAP=512M
	DEFAULT_SOLR_PORT=8983
	DEFAULT_X_WHICH=/usr/bin/which
	DEFAULT_ZK_CLIENT_PORT=2181
	DEFAULT_ZK_ELECTION_PORT=3888
	DEFAULT_ZK_LEADER_PORT=2888
	##### End Setup
	#
	#----
	# DO NOT EDIT BELOW THIS LINE WITHOUT GUIDANCE
	#----

	if [ -z "${AGENT_HEAP}" ]; then
	AGENT_HEAP="${DEFAULT_AGENT_HEAP}"
	fi

	if [ -z "${AGENT_MAIN_ETC_DIR}" ]; then
	AGENT_MAIN_ETC_DIR="${DEFAULT_AGENT_MAIN_ETC_DIR}"
	fi

	if [ -z "${AGENT_PORT}" ]; then
	AGENT_PORT="${DEFAULT_AGENT_PORT}"
	fi

	if [ -z "${CLOUD_BUILD_ADDRESS}" ]; then
	CLOUD_BUILD_ADDRESS="${DEFAULT_CLOUD_BUILD_ADDRESS}"
	fi

	if [ -z "${CLOUD_BUILD_PORT}" ]; then
	CLOUD_BUILD_PORT="${DEFAULT_CLOUD_BUILD_PORT}"
	fi

	if [ -z "${SOLR_HEAP}" ]; then
	SOLR_HEAP="${DEFAULT_SOLR_HEAP}"
	fi

	if [ -z "${SOLR_PORT}" ]; then
	SOLR_PORT="${DEFAULT_SOLR_PORT}"
	fi

	if [ -z "${X_WHICH}" ]; then
	X_WHICH="${DEFAULT_X_WHICH}"
	fi

	if [ -z "${ZK_CLIENT_PORT}" ]; then
	ZK_CLIENT_PORT="${DEFAULT_ZK_CLIENT_PORT}"
	fi

	if [ -z "${ZK_ELECTION_PORT}" ]; then
	ZK_ELECTION_PORT="${DEFAULT_ZK_ELECTION_PORT}"
	fi

	if [ -z "${ZK_LEADER_PORT}" ]; then
	ZK_LEADER_PORT="${DEFAULT_ZK_LEADER_PORT}"
	fi

	# Write a message to stderr indicating that a command is required.
	# If no command is provided to this function, use a generic message.
	# Exit the script after writing the message.
	exit_err_msg_required_command() {
	REQ_CMD="$1"
	if [ -z "${REQ_CMD}" ]; then
	echo >&2 "A command required to run this script is missing."
	else
	echo >&2 "The ${REQ_CMD} command is required to run this script."
	fi
	err_msg_contact_community
	exit 1
	}

	# Write a message asking the user to contact the Solr community if they
	# feel that there's a problem.
	err_msg_contact_community() {
	echo >&2 "---"
	echo >&2 "If you feel this is in error, please mention the problem"
	echo >&2 "to the Solr community on the mailing list or IRC channel."
	echo >&2 "http://lucene.apache.org/solr/community.html#mailing-lists-irc"
	}

	# Locate directories based based on a script directory passed in as the first
	# argument and set environment variables. The current working directory will
	# be set to the parent of that directory and assigned to SOLR_TIP.
	find_dirs_and_change_cwd() {
	MYDIR="$1"
	cd ${MYDIR}
	cd ..
	SOLR_TIP=`pwd`
	LOCAL_ETC_DIR=${SOLR_TIP}/etc
	SOLR_LIB_DIR=${SOLR_TIP}/lib
	SOLR_TMP_DIR=${SOLR_TIP}/tmp
	SOLR_RUN_DIR=${SOLR_TIP}/run
	}

	# Find required system executables or shell builtin commands and set
	# variables like X_TEMPFILE so the script has a better chance of running
	# on systems where things are installed outside of LSB locations.
	find_system_programs_or_exit() {
	# Make sure the which command is available.
	if [ ! -x "${X_WHICH}" ]; then
	echo >&2 "The command ${X_WHICH} is not found or not executable."
	exit_err_msg_required_command "${X_WHICH}"
	fi

	# Check for the existence of other commands we need.
	locate_command_or_exit tempfile X_TEMPFILE 1
	locate_command_or_exit find X_FIND 1
	locate_command_or_exit xargs X_XARGS 1
	# We look for lsof and netstat, but do not exit
	# if they are not found.
	locate_command_or_exit lsof X_LSOF 0
	locate_command_or_exit netstat X_NETSTAT 0
	# If NEITHER lsof or netstat is found, log a warning message.
	if [-z "${X_LSOF}" ] && [ -z "${X_NETSTAT}" ]; then
	echo >&2 "Neither lsof or netstat found. Will not be able to check for"
	echo >&2 "programs already listening on relevant ports."
	fi
	}

	# Check whether a program exists as a builtin or an executable. Will not
	# validate a command that is a function or an alias. Assign a dynamic
	# variable to the bare program name or an executable file path as required
	# if found, exit the script if not. The first argument is the bare command,
	# the second argument is the variable that will be assigned with the correct
	# command or executable. The third argument is an exit flag -- a numeric
	# boolean value (usually 0 or 1) indicating whether or not a missing program
	# will cause a script exit. A missing program will result in an error message
	# whether an exit is forced or not. The first two arguments are required.
	# The exit flag will default to 1 if not present. If the variable mentioned
	# as the second argument is already defined, then the value of that variable
	# will override the first argument to this script and tested to make sure it
	# is a valid command. This allows somebody to define variables like X_TEMPFILE
	# in advance to override the automatic detection, while making sure that the
	# explicitly set value is actually a good command.
	locate_command_or_exit() {
	PRGNAME=$1
	shift
	PRGVAR=$1
	shift
	EXITFLAG=$1

	if [ -z "${PRGNAME}" ] \|\| [ -z "${PRGVAR}" ]; then
	echo >&2 "locate_command_or_exit routine missing required arguments."
	echo >&2 "Aborting script."
	err_msg_contact_community
	exit 1
	fi

	if [ -z "${EXITFLAG}" ]; then
	EXITFLAG=1;
	fi

	BADPROG=0
	if [ -n "${!PRGVAR}" ]; then
	echo >&2 "The ${PRGNAME} command has been predefined as ${!PRGVAR}."
	PRGNAME="${!PRGVAR}"
	fi

	CMD_TYPE=`type -t ${PRGNAME}`
	if [ "${CMD_TYPE}" == "builtin" ]; then
	eval ${PRGVAR}="\${PRGNAME}"
	elif [ "${CMD_TYPE}" == "file" ]; then
	XPATH=`"${X_WHICH}" "${PRGNAME}"`
	RET=$?
	if [ $RET -eq 0 ]; then
	if [ -x "${XPATH}" ]; then
	eval ${PRGVAR}="\${XPATH}"
	else
	BADPROG=1
	fi
	else
	BADPROG=1
	fi
	else
	BADPROG=1
	fi

	if [ ${BADPROG} -ne 0 ]; then
	echo >&2 "The ${PRGNAME} command is not found or not executable."
	echo >&2 "The ${PRGVAR} env variable can explicitly set its location."
	if [ ${EXITFLAG} -ne 0 ]; then
	exit_err_msg_required_command "${PRGNAME}"
	fi
	fi
	return 0
	}

	# Find Java and set the JAVA variable.
	# Exit script if unable to locate a java executable.
	find_java_or_exit() {
	JAVA=
	if [ -n "$SOLR_JAVA_HOME" ]; then
	echo >&2 "SOLR_JAVA_HOME found, using it as JAVA_HOME."
	JAVA_HOME="$SOLR_JAVA_HOME"
	fi

	if [ -n "$JAVA_HOME" ]; then
	for java in "${JAVA_HOME}/bin/amd64/java" "${JAVA_HOME}/bin/java"; do
	if [ -x "$java" ]; then
	JAVA="$java"
	break
	fi
	done
	if [ -z "$JAVA" ]; then
	echo >&2 "The currently defined JAVA_HOME (${JAVA_HOME}) refers"
	echo >&2 "to a location where Java could not be found. Aborting."
	echo >&2 "Either fix the variable or remove it from the environment"
	echo >&2 "so that the system PATH will be searched."
	err_msg_contact_community
	exit 1
	fi
	else
	X_JAVA=`"${X_WHICH}" java`
	if [ -x "${X_JAVA}" ]; then
	JAVA=${X_JAVA}
	else
	echo >&2 "Unable to locate a java executable."
	err_msg_contact_community
	exit 1
	fi
	fi
	return 0
	}

	# Start the agent. Will pass all parameters to the startup.
	# The first parameter is the properties file to use.
	agent_start() {
	start_agent_program $@ start
	}

	# Start the agent program with a commandline parameter that tells it
	# to examine its config and the system, and use what it finds to create
	# a bunch of environment variables. The agent will output the commands
	# for the variables to stdout.
	agent_get_env() {
	start_agent_program get_env
	return $?
	}

	# Start the agent with arguments sent to this function.
	# Removes all options (things like -D), leaving only commands for the agent.
	# Will set a SOLR_AGENT_PROPERTIES sysprop with that variable value.
	start_agent_program() {
	CP_JARS=`get_jars_for_classpath ${SOLR_TIP}/lib/log ${SOLR_TIP}/lib/solrj`

	OPTIND=1
	while getopts ":D:" opt; do
	case ${opt} in
	D)
	# Do nothing. This will remove the option. May not need this case.
	;;
	*)
	# Do nothing. This will remove the option.
	;;
	esac
	done
	shift $((OPTIND -1))

	$JAVA -Xmx${AGENT_HEAP} -cp ${CP_JARS} -DSOLR_AGENT_PROPERTIES="${SOLR_AGENT_PROPERTIES}" -jar lib/agent.jar $@
	return $?
	}

	# Given a list of path locations, recursively find all the jars and write a
	# classpath string to stdout.
	get_jars_for_classpath() {
	get_files_for_classpath jar $@
	}

	# Given an extension and a list of of path locations, recursively find all
	# the files with that extension and write a classpath string to stdout. To
	# include all files, pass an equal sign in as the extension.
	get_files_for_classpath() {
	CP_EXTENSION=$1
	shift

	if [ "${CP_EXTENSION}" == "=" ]; then
	CP_FILESPEC="*"
	else
	CP_FILESPEC="*.${CP_EXTENSION}"
	fi

	DETECTED_CLASSPATH=
	ADDED_FIRST_CP_ENTRY=
	KEEP_RUNNING=true
	while [ -n "${KEEP_RUNNING}" ]; do
	CHECKDIR=$1
	shift
	if [ -n "${CHECKDIR}" ]; then
	if [ -d "${CHECKDIR}" ]; then
	while IFS= read -r -d '' line; do
	add_to_detected_classpath "$line"
	done < <(${X_FIND} ${CHECKDIR} -type f -name "${CP_FILESPEC}" -print0)
	fi
	else
	KEEP_RUNNING=
	fi
	done
	echo "$DETECTED_CLASSPATH"
	}

	add_to_detected_classpath() {
	CP_ENTRY="$1"
	if [ -n "${ADDED_FIRST_CP_ENTRY}" ]; then
	# If the first entry in the classpath has been added
	# we add a colon before the entry as a separator.
	CP_ENTRY=":${CP_ENTRY}"
	fi
	# Set the value to indicate the first entry has been added.
	ADDED_FIRST_CP_ENTRY=true
	DETECTED_CLASSPATH="${DETECTED_CLASSPATH}${CP_ENTRY}"
	}

	# Locate the agent properties file based on available information.
	# The SOLR_AGENT_PROPERTIES variable may be empty after this runs,
	# but only if this is a non-service install.
	find_agent_properties_or_exit() {
	# First, if service name is not set, try to figure out a service name.
	# When no service name set and only one service is installed, we assume
	# that service. If multiple services installed and no name is set, the
	# script will abort.
	if [ -z "${SOLR_SERVICE_NAME}" ]; then
	SOLR_SERVICES_CONFIG=${LOCAL_ETC_DIR}/services.conf
	declare -a SERVICES
	if [ -r "${SOLR_SERVICES_CONFIG}" ]; then
	readarray -t SERVICES < ${SOLR_SERVICES_CONFIG}
	fi
	if [ ${#SERVICES[@]} -gt 0 ]; then
	if [ ${#SERVICES[@]} -eq 1 ]; then
	SOLR_SERVICE_NAME=${SERVICES[0]}
	else
	echo >&2 "Multiple services detected in ${SOLR_SERVICES_CONFIG}"
	echo >&2 "SOLR_SERVICE_NAME must be defined to proceed."
	err_msg_contact_community
	exit 1
	fi
	fi
	fi

	# If we reach here, then we have either settled on one service name or
	# there are no services.
	if [ -n "${SOLR_SERVICE_NAME}" ]; then
	echo >&2 "Solr service name ${SOLR_SERVICE_NAME} detected."
	SOLR_AGENT_PROPERTIES=${MAIN_ETC_DIR}/${SOLR_SERVICE_NAME}/solr-agent.properties
	else
	SOLR_AGENT_PROPERTIES=${LOCAL_ETC_DIR}/solr-agent.properties
	fi

	# When running as a service, the agent properties file must exist. When the
	# properties file does not exist, decide whether to exit or use defaults.
	if [ ! -r "${SOLR_AGENT_PROPERTIES}" ]; then
	if [ -n "${SOLR_SERVICE_NAME}" ]; then
	echo >&2 "The ${SOLR_AGENT_PROPERTIES} file is not found or not readable."
	echo >&2 "Service installs must have an agent properties file."
	err_msg_contact_community
	exit 1
	else
	echo >&2 "The ${SOLR_AGENT_PROPERTIES} file is not found or not readable."
	echo >&2 "Proceeding with defaults for a non-service install."
	SOLR_AGENT_PROPERTIES=
	fi
	# TODO: Service recommendation might need to move.
	if [ -z "${SOLR_SERVICE_NAME}" ]; then
	recommend_service
	fi
	fi
	}

	recommend_service() {
	echo >&2 "Non-service install detected."
	echo >&2 "Installing Solr as a service is strongly recommended."
	echo >&2 "https://lucene.apache.org/solr/guide/taking-solr-to-production.html"
	}

	# Determine whether or not the configured version of Java supports the
	# ExitOnOutOfMemoryError flag. Sets JAVA_OOM_EXIT_SUPPORTED with a numeric
	# boolean value and returns the exit code from the attempt to run Java with
	# that option.
	check_oom_exit_supported() {
	$JAVA -Xmx1M -XX:+ExitOnOutOfMemoryError -version > /dev/null 2> /dev/null
	RET=$?
	if [ ${RET} -eq 0 ]; then
	JAVA_OOM_EXIT_SUPPORTED=1
	else
	JAVA_OOM_EXIT_SUPPORTED=0
	fi
	return ${RET}
	}

	# If the BASH_VERSION variable is not set, it is a reasonable indication
	# that the shell we are running in is not bash. If that situation is
	# detected, exit.
	exit_if_no_bash() {
	if [ -z "${BASH_VERSION}" ]; then
	echo >&2 "This script must be run by the bash shell."
	err_msg_contact_community
	exit 1
	fi
	}

	# Exit script if the bash version is too old. Require version 4.
	# The first release of bash 4 was in 2009.
	exit_if_bash_too_old() {
	if [ -n "${BASH_VERSINFO[*]}" ]; then
	if [ "${BASH_VERSINFO[0]}" -lt 4 ]; then
	echo >&2 "Detected bash version is ${BASH_VERSION}."
	echo >&2 "Script needs at least version 4."
	err_msg_contact_community
	exit 1
	fi
	else
	echo >&2 "There was a problem detecting bash version."
	echo >&2 "Aborting because compatibility cannot be detected."
	err_msg_contact_community
	exit 1
	fi
	}