#!/bin/sh

set -e

apt-get -y install curl
cd /tmp
curl -O ftp://ftp5.us.postgresql.org/pub/PostgreSQL//source/v8.2.4/postgresql-8.2.4.tar.gz
cat <<EOF | sha512sum -c
571fc42abd7b06e0fcc33a326796bb28bdcb7e3260d3e4b56e40f0e22517784460829900e2941e978ca253cac7c8e00397c342ba6397a0657b4b68157aa425e9 *postgresql-8.2.4.tar.gz
EOF
adduser --system --home /var/lib/pgdata --no-create-home --gecos "PostgreSQL administrator,,," --group --disabled-login postgres
apt-get -y install libc6-dev gcc make libreadline5-dev zlib1g-dev libssl-dev
tar -zxof postgresql-8.2.4.tar.gz
cd postgresql-8.2.4
./configure
make
make install
# apt-get -y autoremove --purge libc6-dev gcc make libreadline5-dev zlib1g-dev libssl-dev
cd /

#----------------------
# End of installation.
#----------------------

PGSQL_BIN=/usr/local/pgsql/bin

DB=/tmp/duplicatexlogdemo
XLOG_ARCHIVE=/tmp/xlogarchive
PGDATA_BACKUP=/tmp/pgdata_backup.tar.gz
MAKE_BACKUP=/tmp/makepgdatabackup
RESTORE_BACKUP=/tmp/restorepgdatabackup
SERVER_LOG=/tmp/serverlog

mkdir -p $DB
chown postgres:postgres $DB
sudo -u postgres $PGSQL_BIN/initdb -D $DB

mkdir -p $XLOG_ARCHIVE
chown postgres:postgres $XLOG_ARCHIVE

cat <<EOF >$MAKE_BACKUP
#!/bin/sh
sudo -u postgres $PGSQL_BIN/psql -c "SELECT pg_start_backup('testbackup')" >/dev/null
tar -C $DB --exclude=pg_xlog -c . | gzip -c >$PGDATA_BACKUP
sudo -u postgres $PGSQL_BIN/psql -Atc "SELECT pg_xlogfile_name(pg_stop_backup())"
EOF
chmod 755 $MAKE_BACKUP

cat <<EOF >$RESTORE_BACKUP
#!/bin/sh
mkdir -p $DB/pg_xlog/archive_status
echo "restore_command = 'cp $XLOG_ARCHIVE/%f %p'" >$DB/recovery.conf
chown -R postgres:postgres $DB
chmod -R g=,o= $DB
tar -C $DB -zxf $PGDATA_BACKUP
EOF
chmod 755 $RESTORE_BACKUP

echo "archive_command = 'test ! -f $XLOG_ARCHIVE/%f && cp %p $XLOG_ARCHIVE/%f'" >>$DB/postgresql.conf

sudo -u postgres $PGSQL_BIN/pg_ctl start -w -D $DB -l $SERVER_LOG
sudo -u postgres $PGSQL_BIN/psql -c "CREATE DATABASE blah1"
$MAKE_BACKUP
# Create some logs to recover from:
sudo -u postgres $PGSQL_BIN/psql -c "CREATE DATABASE blah2; SELECT pg_switch_xlog()"
sudo -u postgres $PGSQL_BIN/psql -c "CREATE DATABASE blah3; SELECT pg_switch_xlog()"
sudo -u postgres $PGSQL_BIN/psql -c "CREATE DATABASE blah4; SELECT pg_switch_xlog()"
sudo -u postgres $PGSQL_BIN/psql -c "CREATE DATABASE blah5; SELECT pg_switch_xlog()"
sudo -u postgres $PGSQL_BIN/psql -c "CREATE DATABASE blah6; SELECT pg_switch_xlog()"
sudo -u postgres $PGSQL_BIN/pg_ctl stop -D $DB
cd /
rm -Rf $DB
$RESTORE_BACKUP
sudo -u postgres $PGSQL_BIN/pg_ctl start -w -D $DB -l $SERVER_LOG
$MAKE_BACKUP
tail $SERVER_LOG