#!/bin/bash
# PGpool stage 1 recovery script
# Reference: http://michael.stapelberg.de/Artikel/replicated_postgresql_with_pgpool
#
TS=$(date +%Y-%m-%d_%H-%M-%S)
MASTER_HOST=$(hostname -f)
# $1 is {{ psql_data_dir }} while  $3 is {{ psql_data_dir }}
#MASTER_DATA="{{ psql_data_dir }}"
MASTER_DATA="${1}"
RECOVERY_TARGET=${2}
#RECOVERY_DATA="{{ psql_data_dir }}"
RECOVERY_DATA="${3}"

logger "pgpool_recovery_1: MASTER_DATA=$MASTER_DATA"
logger "pgpool_recovery_1: RECOVERY_DATA=$RECOVERY_DATA"

# Ensure that postgres is shut down on the target node
ssh -T $RECOVERY_TARGET sudo /etc/init.d/postgresql stop

# Move the PostgreSQL data directory out of our way.
ssh -T $RECOVERY_TARGET \
    "[ -d $RECOVERY_DATA ] && mv $RECOVERY_DATA $RECOVERY_DATA.$TS"

# We only use archived WAL logs during recoveries, so delete all
# logs from the last recovery to limit the growth.
rm $MASTER_DATA/archive_log/*

# With this file present, our archive_command will actually
# archive WAL files.
touch $MASTER_DATA/archive_log/backup_in_progress

# Perform a backup of the database.
ssh -T $RECOVERY_TARGET \
    "pg_basebackup -h $MASTER_HOST -D $RECOVERY_DATA --xlog"

# Configure the restore_command to use the archive_log WALs we’ll copy
# over in 2nd_stage.sh.
echo "restore_command = 'cp $RECOVERY_DATA/archive_log/%f %p'" | \
    ssh -T $RECOVERY_TARGET "cat > $RECOVERY_DATA/recovery.conf"