pg-92-96-upgrade-centos7.sh

#!/bin/bash

set -e

PG96RepoRpm='https://download.postgresql.org/pub/repos/yum/9.6/redhat/rhel-7-x86_64/pgdg-centos96-9.6-3.noarch.rpm'

error() {
    local -i rc=$1
    shift
    echo "ERROR($rc): $@" >&2
    exit $rc
}

find_bin_dir() {
    local p=$(type -P psql) || return 1
    while test -L "$p"; do
        p=$(readlink -e "$p")
    done
    echo $(dirname "$p")
}

BaseRepo=/etc/yum.repos.d/CentOS-Base.repo
OsRelease=/etc/os-release
PgDataOld= # have to be sure later on
PgDataDir=/var/lib/pgsql/9.6/data
PgBinDir=/usr/pgsql-9.6/bin
PgSetup="$PgBinDir/postgresql96-setup"
PgUpgrade="$PgBinDir/pg_upgrade"
PgBinOld=$(find_bin_dir) || error 1 "Cannot detect old bin dir."
service=/usr/lib/systemd/system/postgresql-9.6.service
include=/lib/systemd/system/postgresql-9.6.service

declare -a RpmsToRemove=(`rpm -qa | grep ^postgresql-`)

exe0="$0"
[ -f "$exe0" ] || exe0=$(type -P "$exe0")

# 7601 /usr/bin/postgres -D /var/lib/pgsql/data -p 5432
last_word=''
while read word; do
    if [ "$last_word" = '-D' ]; then
        PgDataOld="$word"
        break
    fi
    last_word="$word"
done < <(pgrep -a postgres | grep /usr/bin/postgres | tr -s '[ \t]' '\n')

[ -z "$PgDataOld" ] && error 1 "Cannot detect old data location."
[ -d "$PgDataOld/." ] || error 1 "Wrong old data '$PgDataOld' detected."
echo "* Old data dir: '$PgDataOld'"
echo "* Old bin dir : '$PgBinOld'"
echo "* Old RPMs    : ${RpmsToRemove[@]}"

setup_pg_data_dir() {
    local pgdata="$1"
    test -d "$pgdata/data/." || error $? "No valid PG data dir in '$pgdata/data'."
    chown -R postgres.postgres "$pgdata" || error $? "Cannot chown '$pgdata'."
    chmod -R 700 "$pgdata" || error $? "Cannot chmod '$pgdata'."
    chcon -t postgresql_db_t "$pgdata" || error $? "Cannot chcon '$pgdata'."
    chcon -t postgresql_db_t "$pgdata/data" || error $? "Cannot chcon '$pgdata/data'."
    su -c "/usr/pgsql-9.6/bin/initdb -D '$pgdata/data'" postgres
}

test -f "$OsRelease" || error $? "No '$OsRelease' file."
source "$OsRelease"

{ echo "$NAME" | grep -iwq centos; } || error 1 "It's not a CentOS ($NAME)."
[ "$VERSION_ID" != 7 ] && error 1 "I don't know how to upgrade PgSQL on CentOS '$VERSION_ID'."

echo "* Ok, the system pretends to be '$PRETTY_NAME'..."

list_options() {
    grep -o '^[ \t]\+--skip-[^)]\+' < "$exe0"
}

while [ -n "$1" ]; do
    case "$1" in
    --skip-base-repo-fix)   skip_base_repo_fix=yes; shift;;
    --skip-new-repo-pull)   skip_new_repo_pull=yes; shift;;
    --skip-installation)    skip_installation=yes; shift;;
    --skip-upgrade)         skip_upgrade=yes; shift;;
    --skip-systemd-config)  skip_systemd_config=yes; shift;;
    --skip-start-new)       skip_start_new=yes; shift;;
    --skip-remove-old)      skip_remove_old=yes; shift;;
    run|do)                 run_it=yes; shift;;
    *) list_options; error 1 "What did you mean for '$1'?";;
    esac
done

[ -z "$run_it" ] && error 0 "Run was NOT requested."

if [ "$skip_base_repo_fix" != yes ]; then
    test -f "$BaseRepo" || error $? "No repo '$BaseRepo'."
    sed -e 's/\[base\]/&\nexclude=postgresql*/' \
        -e 's/\[updates\]/&\nexclude=postgresql*/' \
        -i "$BaseRepo" || error $? "Cannot edit '$BaseRepo'."
else
    echo "* Ok, I suppose, you've edited the repos ('exclude=postgresql*' in [base] and [updates])..."
fi

if yum repolist 2>/dev/null | grep -E '^(epel|pgdg96)/'; then
    echo "* Ok, I see you've installed EPEL and PGDB96..."
elif [ "$skip_new_repo_pull" != yes ]; then
    yum -y install epel-release  || error $? "Cannot install EPEL."
    yum -y install "$PG96RepoRpm" || error $? "Cannot install '$PG96RepoRpm'."
else
    error 1 "No PGDG96 and/or EPEL repos installed."
fi

if rpm -qa | grep ^postgresql96-; then
    echo "* Ok, it looks like you've installed the PG96 here..."
elif [ "$skip_installation" != yes ]; then
    yum list postgresql* || error $? "I see no PG packages available."
    yum -y install postgresql96 postgresql96-server || error $? "Cannot install GP96."
    test -d "$PgDataDir" || error $? "PG96 still not installed (data)."
    test -d "$PgBinDir" || error $? "PG96 still not installed (bin)."
    test -x "$PgSetup" || error $? "No setup utility '$PgSetup'."
    "$PgSetup" initdb || error $? "Cannot initialize DB."
else
    error 1 "You have no PG96 packages installed."
fi

hack_pg_ctl() {
    mv /usr/bin/pg_ctl{,-orig}
    echo '#!/bin/bash' > /usr/bin/pg_ctl
    echo 'exec "$0"-orig "${@/unix_socket_directory/unix_socket_directories}"' >> /usr/bin/pg_ctl
    chmod +x /usr/bin/pg_ctl
}

unhack_pg_ctl() {
    [ -f /usr/bin/pg_ctl-orig ] && mv -f /usr/bin/pg_ctl{-orig,}
}
trap unhack_pg_ctl EXIT

if [ "$skip_upgrade" != yes ]; then
    test -x "$PgUpgrade" || error $? "No upgade tool '$PgUpgrade'."
    echo "*:*:*:postgres:pg" > ~/.pgpass
    echo "* NOTE: user=postgres password=pg !"
    cmd="$PgUpgrade"
    cmd="$cmd --old-datadir \"$PgDataOld\" --new-datadir \"$PgDataDir\""
    cmd="$cmd --old-bindir \"$PgBinOld\" --new-bindir \"$PgBinDir\""

    hack_pg_ctl

    su -c "cd /tmp && $cmd --check" postgres || error $? "Cannot validate '$PgUpgrade'."
    echo "* Ok, looks like we can upgrade..."
    systemctl stop postgresql.service || error $? "Cannot stop 'postgresql.service'."
    echo "* Ok, migrating..."
    echo "* NOTE: user=postgres password=pg !"
    su -c "cd /tmp && $cmd" postgres || error $? "Cannot run upgrade '$PgUpgrade'."
    echo "* Wow! It looks like the data has been migrated!"
    rm ~/.pgpass
else
    echo "* Ok, skipping the data upgrade..."
fi

if [ "$skip_systemd_config" != yes ]; then
    systemctl enable postgresql-9.6.service || error $? "Cannot enable postgresql service."
    test -f "$service" || error $? "No systemd service '$service'."
    test -f "$include" || error $? "No systemd service template '$include'."
    fn=$(basename "$service")
    cp -v "$service" /etc/systemd/system/ \
        || error $? "Cannot cp '$service' into /etc/systemd/system/."
    echo "include $include" > "/etc/systemd/system/$fn" || error $? "Cannot edit (1) '$fn'."
    cat "$service" >> "/etc/systemd/system/$fn" || error $? "Cannot edit (2) '$fn'."
    systemctl daemon-reload || error $? "Cannot reload daemons."
    systemctl start postgresql-9.6.service || error $? "Cannot try postgresql service."
    systemctl stop postgresql-9.6.service || error $? "Cannot stop postgresql service."
else
    echo "* Ok, I wont configure systemd for you..."
fi

if [ "$skip_start_new" != yes ]; then
    systemctl start postgresql-9.6.service || error $? "Cannot start postgresql service."
    systemctl status postgresql-9.6.service
    echo "* Ok, it looks like you've started the PG96 here..."
fi

if [ "$skip_remove_old" != yes ]; then
    yum -y remove "${RpmsToRemove[@]}" || error $? "Cannot remove '${RpmsToRemove[@]}'."
else
    echo "* Ok, I wont remove your old stuff..."
fi

echo "* Done (you may copy your configs and 'rm -rf $PgDataOld' now)."
# EOF #