Minetest startup script minetest_start.sh

#!/bin/bash

#Author: Ritchie
#Thanks to Pitriss for suggestions and advices
#Licence: WTFPL

#Startup script for minetestserver. Does world backup and world map if mapper is configured.
#Script can be used with cron, then will keep minetestserver running if was stopped. Recommended location for script is /usr/local/bin/.
#You can redirect output from this script to log file, script will inform you what happened if something went wrong.
#Example of line in file /etc/crontab
#*/5 *   * * *   minetest    if [ `ps -e | grep -c minetest` = '0' ]; then /usr/local/bin/minetest_start.sh >> /opt/minetest-data/logs/minetest_start/minetest_start.log; fi >> /dev/null 2>&1

#To know all used variables, run this script with debug parameter: $ ./minetest_start.sh debug

#This script has many checks to ensure proper function of minetestserver. When minetestserver crashes during start for any reason (mostly broken world database file), script will make temporary file according variable named "TEMPFILE" and script in next run will do nothing, only write error message. When you fix minetestserver start, delete that temporary file.

#Script makes symbolic links named "latest" to latest world backup, log file and map image to easily find latest files. You can make symbolic links to that "latest" files everywhere you want (for example latest map image to webserver).

### config section
# All pathes to directories must have a slash "/" at end!

#path to world
WORLD="/opt/minetest/world/classic_technic_game/"
#path to minetest directory
MINETEST="/opt/minetest/"
#path to backup directory
BACKUPS="/opt/minetest-data/world-backups/"
#path to maps directory
MAP_DIR="/opt/minetest-data/maps/"
#path to mapper directory
MAPPER="/opt/minetest-git/minetest-mapper-cpp/"
#path to directory with minetestserver logs
LOGS="/opt/minetest-data/logs/"
#path to temporary directory
TEMP="/opt/minetest-data/temp"
#path to temporary file which is created if minetestserver crashed
TEMPFILE="/opt/minetest-data/minetest_crashed.txt"
#path to startup log where to save text output from minetest_mapper, can be the same as used in crontab file as described above
STARTLOG="/opt/minetest-data/logs/minetest_start/minetest_start.log"
#limit of disc usage in percent, if you have full disc device, script does nothing
DISCMAX="95"

### end of config section

#variable which returns today's date and time in format DDMMYYYY_HH:MM:SS, for example 27102013_21:04:06
NOW="$(date +%d%m%Y_%T)"
#name of world
NAME="$(echo "$WORLD" | awk 'BEGIN { FS = "/" } {print $(NF-1)}')"
#path to minetest/world/
MT_WORLD="$(echo "$WORLD" | awk 'BEGIN { FS = "/"; OFS = "/" } {$(NF-1)=""; print$0}' | rev | cut -c2- | rev)"
#path and name of backup file
BACKUP_TGZ="$BACKUPS$NAME$NOW.tar.gz"
#name of backup file
TGZ="$NAME$NOW.tar.gz"
#path and name of output map image
MAP_OUT="$MAP_DIR$NAME$NOW.png"
#name of output map image
MAP="$NAME$NOW.png"
#path and name of logfile
LOGFILE="$LOGS$NAME$NOW.txt"
#base of filesystem path to temporary directory to check free space
BASE="$(echo "$TEMP" | awk -F"/" '{print "/"$2}')"

#debug of variables
if [ "$1" = "debug" ] ; then
echo WORLD $WORLD
echo MINETEST $MINETEST
echo BACKUPS $BACKUPS
echo MAP_DIR $MAP_DIR
echo MAPPER $MAPPER
echo LOGS $LOGS
echo NOW $NOW
echo NAME $NAME
echo MT_WORLD $MT_WORLD
echo BACKUP_TGZ $BACKUP_TGZ
echo TGZ $TGZ
echo MAP_OUT $MAP_OUT
echo MAP $MAP
echo LOGFILE $LOGFILE
echo TEMP $TEMP
echo BASE $BASE
echo TEMPFILE $TEMPFILE
echo STARTLOG $STARTLOG
echo DISCMAX $DISCMAX
exit 0
fi

#date and time when job started
echo "Script started at time" $NOW

#check for temp file
if [ ! -f "$TEMPFILE" ] ;
then
  #check for available disk space
  if [ `df | grep $BASE | awk '{print $5}' | rev | cut -b2- | rev` -lt $DISCMAX ] ;
  then
    #clean temp directory
    cd $TEMP ; rm -rf * ; cd - &> /dev/null
    #copy world to temp directory
    cp -rp $WORLD $TEMP

    #check if copy succeeded or failed
    if [ $? == 0 ] ;
    then
      #run minetestserver
      $MINETEST/bin/minetestserver &> $LOGFILE &
      #wait some time to let minetestserver load all needed data
      sleep 10

      #check if minetestserver is running
      if [ `ps -e | grep -c minetestserver` -ge 1 ] ;
      then
        #backup of world to *tar.gz in backup directory
        cd $TEMP ; tar cf - $NAME | gzip -9 - > $BACKUP_TGZ ; cd - &> /dev/null
        #make symbolic link to $BACKUPS$NAME-latest.tar.gz
        cd $BACKUPS ; ln -sf $TGZ $NAME-latest.tar.gz ; cd - &> /dev/null
        #make symbolic link from actual logfile to logfile-latest.txt
        cd $LOGS ; ln -sf $LOGFILE $NAME-latest.txt ; cd - &> /dev/null

        #check if mapper is ready
        if [ -x "$MAPPER/minetest_mapper" ] ;
        then
          #do a map
          $MAPPER/minetest_mapper --draworigin --geometry -3000:-3000+6000+6000 -i $TEMP/$NAME/ -o $MAP_OUT >> $STARTLOG 2>&1
          #symbolic link to $MAP_DIR$NAME-latest.png
          cd $MAP_DIR ; ln -sf $MAP $NAME-latest.png ; cd - &> /dev/null
        else
          echo "Warning: minetest_mapper is not ready"
        fi

      else
        echo $NOW >> $TEMPFILE
        echo "ERROR: minetestserver crashed"
      fi

    else
      echo "ERROR: copying failed"
    fi

    #clean temp directory
    cd $TEMP ; rm -rf * ; cd - &> /dev/null
  else
    echo "ERROR: no space left on device"
  fi

else
  echo "ERROR: temporary file exists - minetestserver crashed"
fi