Simple backup script for a postgres database

backup-db

#!/bin/bash
#
# Script to backup local
# Postgres database
# Run via cron job
#
###########################

###########################
#
# Config section
#
###########################
BACKUP_USER='postgres'

BACKUP_DIR="/data/db-nightly-backups"

BZIP=yes

FILE_NAME="myapp.database"

#########################################
#
# Pre Backup Checks
#
#########################################

# Make sure we're running as the required backup user
if [ "$BACKUP_USER" != "" -a "$(id -un)" != "$BACKUP_USER" ]; then
  echo "This script must be run as $BACKUP_USER not "$(id -un)" Exiting." 1>&2
  exit 1;
fi;

# Make sure the $BACKUP_DIR exists
if [ ! -d "$BACKUP_DIR" ]; then
  echo "Directory $BACKUP_DIR does not exist. Exiting." 1>&2
  exit 1;
fi

# Make sure they can write to $BACKUP_DIR
if [ ! -w $BACKUP_DIR ] ; then
  echo "Directory $BACKUP_DIR cannot be written to by $BACKUP_USER Exiting." 1>&2
  exit 1
fi


#########################################
#
#Timestamp That pre-pends the backup name
#Timestamp to track how long backup takes
#
#########################################
DATE_STAMP=`date +"%Y_%m_%d--%H_%M"`
TIMER_START=`date +%s`

#########################################
#
# Backup the Database
#
#########################################

FULL_FILE_NAME=$BACKUP_DIR/$DATE_STAMP"_"$FILE_NAME

if [ $BZIP = "yes" ]
then
  FULL_FILE_NAME=$FULL_FILE_NAME.bz2
  echo "Backing up $FULL_FILE_NAME"
  if ! pg_dumpall | bzip2 -vf > $FULL_FILE_NAME; then
    echo "pg_dumpall failed. $FULL_FILE_NAME. Exiting." 1>&2
    exit 1
  fi
else
  echo "Backing up $FULL_FILE_NAME"
  if ! pg_dumpall > $FULL_FILE_NAME; then
    echo "pg_dumpall failed. $FULL_FILE_NAME. Exiting." 1>&2
    exit 1
  fi
fi


#########################################
#
# Confirm
#
#########################################

# If using bzip2 confirm the file is not corrupt
if [ $BZIP = "yes" ]
then
  echo "Confirming BZIP is valid"
  if ! bzip2 -tv $FULL_FILE_NAME; then
    echo "BZIP backup is corrupt. $FULL_FILE_NAME. Exiting." 1>&2
    exit 1
  fi
fi

#########################################
#
# Backup Complete now notify!
#
#########################################

TIMER_END=`date +%s`
TOTAL_TIME=$(($TIMER_END - $TIMER_START))
STR_TIME="$(($TOTAL_TIME / 60)) min $(($TOTAL_TIME % 60)) sec"

#Account for backups taking hours
if (( $TOTAL_TIME >= 3600 ))
then
  STR_TIME="$(($TOTAL_TIME / 3600)) hours $(( min=$TOTAL_TIME / 60, min % 60)) min $(($TOTAL_TIME % 60)) sec"
fi

echo ""
echo "================================"
echo ""
echo "    DATABASE Backup Complete"
echo "    Database save at "
echo "      $FULL_FILE_NAME"
echo "    BACKUP took $STR_TIME"
echo ""
echo "================================"

exit 0