# -*- mode: sh; sh-basic-offset: 3; indent-tabs-mode: nil; -*-
# vim: set filetype=sh sw=3 sts=3 expandtab autoindent:
#
# PostgreSQL handler script for backupninja
#

getconf backupdir /var/backups/postgres
getconf databases all
getconf compress yes
# format maps to pg_dump --format= option, old/default was plain
getconf format plain

localhost=`hostname`

# Make sure that the system to backup has the needed executables
if [ "$databases" == "all" ] && [ "$format" = "plain" ]; then
   [ -x "`which $PGSQLDUMPALL`" ] || \
      fatal "Can't find $PGSQLDUMPALL."
elif [ "$format" != "plain" ]; then
   [ -x "`which $PGSQLDUMPALL`" ] || \
      fatal "Can't find $PGSQLDUMPALL."
   [ -x "`which $PGSQLDUMP`" ] || \
      fatal "Can't find $PGSQLDUMP."
   [ -x "`which $PSQL`" ] || \
      fatal "Can't find $PSQL."
else
   [ -x "`which $PGSQLDUMP`" ] || \
      fatal "Can't find $PGSQLDUMP."
fi

# create backup dir
[ -d $backupdir ] || (debug "mkdir -p $backupdir"; mkdir -p $backupdir)
[ -d $backupdir ] || fatal "Backup directory '$backupdir' does not exist, and could not be created."

# give backup dir the good uid and permissions
pguid=`getent passwd $PGSQLUSER | @AWK@ -F: '{print $3}'`
[ -n "$pguid" ] || fatal "No user called $PGSQLUSER."

debug "chown $pguid $backupdir"
chown $pguid $backupdir
debug "chmod 700 $backupdir"
chmod 700 $backupdir


# If we are using the custom (best) or tar pg_dump format, and
# dumping "all" databases, we will substitute "all" for a list
# of all non-template databases to avoid the use of pg_dumpall.
dumpglobals="no"
if [ "$databases" = "all" ] && [ "$format" != "plain" ]; then
   execstr="su - $PGSQLUSER -c 'psql -AtU $PGSQLUSER -c \"SELECT datname FROM pg_database WHERE NOT datistemplate\"'"
   debug execstr
   dblist=""
   for db in $(eval $execstr 2>&1); do
      dblist="$dblist $db"
   done
   if [ "$dblist" != "" ]; then
      databases="$dblist"
   fi
   # Dump globals (pg_dumpall -g) for roles and tablespaces
   dumpglobals="yes"
fi


# if $databases = all, use pg_dumpall
if [ "$databases" == "all" ]; then
   if [ "$compress" == "yes" ]; then
      execstr="su - $PGSQLUSER -s /bin/bash -c \"set -o pipefail ; $PGSQLDUMPALL | $GZIP $GZIP_OPTS > '$backupdir/${localhost}-all.sql.gz'\""
   else
      execstr="su - $PGSQLUSER -c \"$PGSQLDUMPALL > '$backupdir/${localhost}-all.sql'\""
   fi
   debug "$execstr"
   if [ ! $test ]; then
      output=`eval $execstr 2>&1`
      code=$?
      if [ "$code" == "0" ]; then
         debug "$output"
         info "Successfully finished dump of pgsql cluster"
      else
         warning "$output"
         warning "Failed to dump pgsql cluster"
      fi
   fi

# else use pg_dump on each specified database
else
   # If we're not doing plain format, database=all may now be database=list
   # so we track the database=all selection in dumpglobals which tells us
   # to also dump the roles and tablespaces via pg_dumpall -g
   if [ "$dumpglobals" = "yes" ]; then
      globalscmd=""
      if [ "$compress" == "yes" ]; then
         globalscmd="set -o pipefail ; $PGSQLDUMPALL -g | $GZIP $GZIP_OPTS > '$backupdir/globals.sql.gz'"
      else
         globalscmd="$PGSQLDUMPALL -g > '$backupdir/globals.sql'"
      fi
      execstr="su - $PGSQLUSER -s /bin/bash -c \"$globalscmd\""
      debug "$execstr"
      if [ ! $test ]; then
         output=`eval $execstr 2>&1`
         code=$?
         if [ "$code" == "0" ]; then
            debug "$output"
            info "Successfully finished pgsql globals (roles and tablespaces) dump"
         else
            warning "$output"
            warning "Failed to dump pgsql globals (roles and tablespaces)"
         fi
      fi
   fi
   for db in $databases; do
      dumpext="sql"
      if [ "$format" != "plain" ]; then
         dumpext="pg_dump"
      fi
      # To better support the backupninja global GZIP and rsync-friendly GZIP_OPTS
      # the custom archive format is told to disable compression. The plain format
      # is uncompressed by default and the tar format doesn't support pg_dump compression.
      disablecustomcompress=""
      if [ "$format" = "custom" ]; then
         disablecustomcompress="--compress=0"
      fi
      dumpcmd=""
      globalscmd=""
      if [ "$compress" == "yes" ]; then
         dumpcmd="set -o pipefail ; $PGSQLDUMP --format=$format ${disablecustomcompress} $db | $GZIP $GZIP_OPTS > '$backupdir/${db}.${dumpext}.gz'"
      else
         dumpcmd="$PGSQLDUMP --format=$format ${disablecustomcompress} $db > '$backupdir/${db}.${dumpext}'"
      fi
      execstr="su - $PGSQLUSER -s /bin/bash -c \"$dumpcmd\""
      debug "$execstr"
      if [ ! $test ]; then
         output=`eval $execstr 2>&1`
         code=$?
         if [ "$code" == "0" ]; then
            debug "$output"
            info "Successfully finished dump of pgsql database ${db}"
         else
            warning "$output"
            warning "Failed to dump pgsql database ${db}"
         fi
      fi
   done
fi

return 0