## mark a section (Learn more)

#!/bin/bash #================================================================================ # /engineyard/bin/monit_merb_mpc #================================================================================ # This script controls the multi-process Merb 1.0 service # # Do not forget to ensure this script is executable: # $ chmod a+x /engineyard/bin/monit_merb_mpc #================================================================================ export PATH=/bin:/usr/bin:/usr/local/bin:/usr/local:/opt/bin:$PATH usage() { cat <<END Usage: $0 <application> <action> [options] application - the name of the merb application being controlled action - the task being performed. This can be one of: - start_master - stop_master - register_worker - restart_worker The action determines what further arguments and options are allowed. The register_worker and restart worker take a numberic argument for the socket or port id of the worker. The start_master action takes the following options: -a adapter {*mongrel,thin} -s use sockets instead of ports Note: not valid for mongrel adapter -c count Number of worker processes - defaults to 1 -n start starting index - defaults to 5000 for ports, 0 for sockets There are also the following universal options: -e environment {*production,staging,develompent,testing} -h help - Print this. Notes: * indicates the default value. END exit 1 } # # Utility functions # log() { reason=${MONIT_EVENT-Invoked} msg="[`date +"%Y/%m/%d %H:%M:%S"` - ${application}/${environment}:$reason] $1" echo $msg >> $monit_log_file echo $msg >&2 } get_pid() { # Check for pid_file pid='' if [ -e $pid_dir/$real_pid_file ] ; then pid=`cat $pid_dir/$real_pid_file` if [ ! -z "$pid" ] && [ ! -d "/proc/$pid" ] ; then pid="" rm $pid_dir/$real_pid_file fi fi # pid file is non-existant or empty - get pid from process list if [ "$worker_id" = "main" ]; then sig="master" elif [ $interface = 'sockets' ] ; then sig="worker (socket $worker_id .*)" else sig="worker (port $worker_id)" fi ps_pid_list="`ps auxww | grep "merb" | grep -v "grep" | grep " $process_name : $sig" `" ps_pid_count=`echo "$ps_pid_list" | wc -l` ps_pid=`echo "$ps_pid_list" | head -n1 - | awk '{print $2}'` if [ "$ps_pid" = "$pid" ]; then echo "$pid" elif [ -z "$pid" ]; then echo "$ps_pid" elif [ "$ps_pid_count" -gt 1 ]; then # search for pid in multi-pid list ps_pid=`echo "$ps_pid_list" | grep " $pid " | head -n1 - | awk '{print $2}'` echo "$ps_pid" fi } get_pid_list() { current_pid="$1" list="$current_pid" for child in `ps --ppid "$current_pid" | awk '{print $1}' | grep -v PID`; do list="$list $child `ps --ppid "$child" | awk '{print $1}' | grep -v PID`" done echo "$list" } get_master_pids() { list="`ps auxw | grep 'merb' | grep -v 'grep' | grep ": $process_name : master" | awk '{print $2}'`" echo "$list" } get_remaining_pids() { list="" for pid in `echo "$@"` ; do if [ -d "/proc/$pid" ] ; then list="$list $pid" fi done echo "$list" } mdk_merb() { pid=$1 remaining_pids=`get_pid_list $pid` log "Stopping merb processes for $application $environment: $remaining_pids" kill -INT "$pid" result="$?" sleep 1 remaining_pids=`get_remaining_pids "$remaining_pids"` if [ "$result" -eq 0 ] ; then timeout=9 while [ $timeout -gt 0 ] && [ ! -z "$remaining_pids" ] ; do sleep 1 timeout=$(( $timeout - 1 )) remaining_pids=`get_remaining_pids "$remaining_pids"` done fi if [ ! -z "$remaining_pids" ] ; then log "Force-killing the remaining processes: $remaining_pids" for pid in `echo "$remaining_pids"` ; do kill -KILL $pid done fi } start_merb() { # Get the user and group info, and set up environmental variables user=`stat -c"%U" /data/$application/current` group=`stat -c"%G" /data/$application/current` INLINEDIR="/data/$application/.ruby_inline" ; export INLINEDIR HOME=`eval "dirname ~${user}/."`; export HOME # Check that the name is not specified in the config/init.rb file if [ `egrep "^[[:space:]]*config\[:name\][[:space:]]*=" "$app_dir/config/init.rb" > /dev/null 2>&1; echo $?` -eq 0 ]; then log "FAILED TO START: config[name] directive in config/init.rb incompatible with $0 -- please remove" exit 1 fi # Check if pid already exists old_pids=`get_master_pids` if [ ! -z "$old_pids" ] ; then log "Killing off pre-existing merb processes: $old_pids" for master_pid in `echo "$old_pids"` ; do mdk_merb $master_pid done fi # clean up existing left-over pid files rm -rf "$pid_dir/${pid_file/\%s/*}" cd $app_dir log "Starting merb master process for $application on $interface $start_id to $(($start_id + $count - 1)) in the $environment environment, using adapter $adapter." command="$merb --name "$process_name" -d -u $user -G $group -a $adapter -L $app_log_file -e $environment -m $app_dir -c $count -P '$pid_dir/$pid_file'" if [ "$interface" = "sockets" ]; then command="$command -o '$socket_dir/$socket_file' -s $start_id" else command="$command -p $start_id" fi log "$command" eval "$command" timeout=10 while [ ! -f "$pid_dir/$real_pid_file" ] || [ -z `get_pid` ] || [ "`get_pid`" != "`cat "$pid_dir/$real_pid_file"`" ] ; do sleep 1 timeout=$(( $timeout - 1 )) if [ $timeout -le 0 ] ; then log "FATAL: master process did not drop a correct pid file within 10 seconds" exit 1 fi done exit 0 } stop_merb() { cd $app_dir pid=`get_pid` if [ -z "$pid" ] ; then log "FATAL: Cannot stop merb master process for $application $environment: process not found" exit 1 fi mdk_merb "$pid" exit 0 } register_worker() { log "Registering merb worker $worker_id for $application in the $environment environment" sleep 6 timeout=14 pid="`get_pid`" while [ ! -f "$pid_dir/$real_pid_file" ] || [ -z "$pid" ] || [ "$pid" != "`cat "$pid_dir/$real_pid_file"`" ] ; do timeout=$(( $timeout - 2 )) if [ $timeout -le 0 ] ; then if [ ! -z "$pid" ] ; then #merb istn't writing the pid file -- take over and write the damn file log "WARNING: worker $worker_id did not drop a correct pid file within 20 seconds -- manually creating it with pid $pid" echo "$pid" > "$pid_dir/$real_pid_file" else log "FATAL: worker $worker_id did not drop a correct pid file within 20 seconds" exit 1 fi fi sleep 2 pid="`get_pid`" done exit 0 } restart_worker() { if [ "`ps -elf | grep -c "$0 *$application *stop_master"`" -gt 0 ] ; then log "Skipping restart of worker $worker_id - master is being shut down" exit 2 fi log "Restarting merb worker $worker_id for $application in the $environment environment" pid=`get_pid` if [ -z "$pid" ] ; then log "FATAL: Cannot stop merb worker process for $application/$environment: process not found" exit 1 fi command="$merb -K $worker_id -e $environment -m $app_dir -P '$pid_dir/$real_pid_file'" log "$command" eval "$command" result="$?" timeout=10 while [ -d /proc/$pid ] && [ $timeout -gt 0 ] ; do sleep 1 timeout=$(( $timeout - 1 )) done if [ -d /proc/$pid ] ; then log "Worker process did not restart gracefully, forcing restart" kill -KILL $pid fi exit 0 } app_check() { if [ "$adapter" -eq "thin" ] ; then if [ -S "$socket_dir/$socket_file" ] ; then log "The socket file exists and is a socket then check it for a response" log "Checking socket ($app_checker $socket_dir/$socket_file)" $app_checker $socket_dir/$socket_file return $? else log "Socket file $socket_dir/$socket_file does not exist and/or is not a socket." return 1 fi else $app_checker $interf fi } # ----------------------------------------------------------------------------- # Main Logic # ----------------------------------------------------------------------------- # Must be run as root if [ "`whoami`" != "root" ]; then logger -t `basename $0` -s "Must be run as root" exit 1 fi # Set defaults environment="production" adapter="mongrel" interface="ports" count="1" start_id="auto" worker_id="main" application=$1 action=$2 lock="$0 *$application *$action" shift 2 if [ "$application" = "" ] || [ "$action" = "" ] || [ "$application" = "-h" ] || [ "$action" = "-h" ]; then usage fi if [ "$action" = "restart_worker" ] || [ "$action" = "register_worker" ] ; then worker_id="$1" lock="$lock *$worker_id" shift 1 fi # Parsing the options. if [ "$action" = "start_master" ]; then while getopts "e:a:sn:ic:h" option ; do case $option in e) environment=$OPTARG ;; a) adapter=$OPTARG ;; s) interface="sockets";; n) start_id=$OPTARG ;; c) count=$OPTARG ;; ?) usage ;; esac done # Validations if [ "$start_id" = "auto" ] ; then if [ "$interface" = "sockets" ]; then start_id=0; else start_id=5000; fi fi if [ "$adapter" = "mongrel" ] && [ "$interface" = "sockets" ]; then echo "Illegal configuration: mongrels cannot use sockets" usage fi else while getopts "e:a:sn:h" option ; do case $option in e) environment=$OPTARG ;; ?) usage ;; esac done fi shift $(($OPTIND - 1)) # Setup control variables log_dir="/var/log/engineyard/$application" monit_log_file="$log_dir/monit.control.log" app_dir="/data/$application/current" app_log_file="$app_dir/log/$environment.log" pid_dir=$log_dir pid_file="$application-$environment-merb.%s.pid" real_pid_file="${pid_file/\%s/$worker_id}" process_name="${application}_$environment" pinger="/engineyard/bin/port_ping" merb="/usr/bin/merb" if [ -e $app_dir/bin/merb ] ; then merb="$app_dir/bin/merb" fi if [ "$interface" = "sockets" ] ; then pinger="/engineyard/bin/socket_ping" socket_dir=$log_dir socket_file="$application-$environment-merb.%s.sock" fi mkdir -p $log_dir && touch $monit_log_file # If the pid_file exists check for running thin # also ensure that it represents the running thin # Exit if the application does not exist. if [ ! -d "$app_dir" ]; then log "$app_dir does not exist." usage fi # Check if the process is already running mypid="$$" running_script_count="`ps -elf | grep "$lock\( \|\$\)" | awk '{printf " %s %s \n", $4, $5}' | grep -c -v " $mypid "`" if [ "$running_script_count" -gt 0 ] ; then log "already running $action for $worker_id - refusing to run it again" exit 2 fi # Set the pids. case "$action" in start_master) start_merb ;; stop_master) stop_merb ;; register_worker) register_worker ;; restart_worker) restart_worker $worker_id ;; restart_all) # Not used by Monit, "manually" called. # Gracefully bring up a new instance # Start a new one so that it is waiting on the port/socket bindings # Then stop the old ones. echo "restart_all not yet implemented" echo "" usage ;; *) usage ;; esac exit 0

This paste will be private.