#!/bin/bash

#

# postgresql-setup - Initialization and upgrade operations for PostgreSQL

test x"$PGSETUP_DEBUG" != x && set -x

# PGVERSION is the full package version, e.g., 9.0.2

# Note: the specfile inserts the correct value during package build

PGVERSION=xxxx

# PGMAJORVERSION is the major version, e.g. 9.0

PGMAJORVERSION=xxxx

# PGENGINE is the directory containing the postmaster executable

PGENGINE=xxxx

# PREVMAJORVERSION is the previous major version, e.g., 8.4, for upgrades

PREVMAJORVERSION=xxxx

# PREVPGENGINE is the directory containing the previous postmaster executable

PREVPGENGINE=xxxx

# Absorb configuration settings from the specified systemd service file,

# or the default "postgresql" service if not specified

SERVICE_NAME="$2"

if [ x"$SERVICE_NAME" = x ]; then

    SERVICE_NAME=postgresql

fi

# Pathname of the RPM distribution README

README_RPM_DIST=xxxx

USAGE_STRING=$"

Usage: $0 {initdb|upgrade} [SERVICE_NAME]

Script is aimed to help sysadmin with basic database cluster administration.

The SERVICE_NAME is used for selection of proper unit configuration file; For

more info and howto/when use this script please look at the docu file

$README_RPM_DIST.  The 'postgresql'

string is used when no SERVICE_NAME is explicitly passed.

Available operation mode:

  initdb        Create a new PostgreSQL database cluster.  This is usually the

                first action you perform after PostgreSQL server installation.

  upgrade       Upgrade PostgreSQL database cluster to be usable with new

                server.  Use this if you upgraded your PostgreSQL server to

                newer major version (currently from $PREVMAJORVERSION \

to $PGMAJORVERSION).

Environment:

  PGSETUP_INITDB_OPTIONS     Options carried by this variable are passed to

                             subsequent call of \`initdb\` binary (see man

                             initdb(1)).  This variable is used also during

                             'upgrade' mode because the new cluster is actually

                             re-initialized from the old one.

  PGSETUP_PGUPGRADE_OPTIONS  Options in this variable are passed next to the

                             subsequent call of \`pg_upgrade\`.  For more info

                             about possible options please look at man

                             pg_upgrade(1).

  PGSETUP_DEBUG              Set to '1' if you want to see debugging output."

# note that these options are useful at least for help2man processing

case "$1" in

    --version)

        echo "postgresql-setup $PGVERSION"

        exit 0

        ;;

    --help|--usage)

        echo "$USAGE_STRING"

        exit 0

        ;;

esac

# this parsing technique fails for PGDATA pathnames containing spaces,

# but there's not much I can do about it given systemctl's output format...

PGDATA=`systemctl show -p Environment "${SERVICE_NAME}.service" |

                sed 's/^Environment=//' | tr ' ' '\n' |

                sed -n 's/^PGDATA=//p' | tail -n 1`

if [ x"$PGDATA" = x ]; then

    echo "failed to find PGDATA setting in ${SERVICE_NAME}.service"

    exit 1

fi

PGPORT=`systemctl show -p Environment "${SERVICE_NAME}.service" |

                sed 's/^Environment=//' | tr ' ' '\n' |

                sed -n 's/^PGPORT=//p' | tail -n 1`

if [ x"$PGPORT" = x ]; then

    echo "failed to find PGPORT setting in ${SERVICE_NAME}.service"

    exit 1

fi

# Log file for initdb

PGLOG=/var/lib/pgsql/initdb.log

# Log file for pg_upgrade

PGUPLOG=/var/lib/pgsql/pgupgrade.log

export PGDATA

export PGPORT

# For SELinux we need to use 'runuser' not 'su'

if [ -x /sbin/runuser ]; then

    SU=runuser

else

    SU=su

fi

script_result=0

# code shared between initdb and upgrade actions

perform_initdb(){

    if [ ! -e "$PGDATA" ]; then

        mkdir "$PGDATA" || return 1

        chown postgres:postgres "$PGDATA"

        chmod go-rwx "$PGDATA"

    fi

    # Clean up SELinux tagging for PGDATA

    [ -x /sbin/restorecon ] && /sbin/restorecon "$PGDATA"

    # Create the initdb log file if needed

    if [ ! -e "$PGLOG" -a ! -h "$PGLOG" ]; then

        touch "$PGLOG" || return 1

        chown postgres:postgres "$PGLOG"

        chmod go-rwx "$PGLOG"

        [ -x /sbin/restorecon ] && /sbin/restorecon "$PGLOG"

    fi

    # Initialize the database

    initdbcmd="$PGENGINE/initdb --pgdata='$PGDATA' --auth='ident'"

    initdbcmd+=" $PGSETUP_INITDB_OPTIONS"

    $SU -l postgres -c "$initdbcmd" >> "$PGLOG" 2>&1 < /dev/null

    # Create directory for postmaster log files

    mkdir "$PGDATA/pg_log"

    chown postgres:postgres "$PGDATA/pg_log"

    chmod go-rwx "$PGDATA/pg_log"

    [ -x /sbin/restorecon ] && /sbin/restorecon "$PGDATA/pg_log"

    if [ -f "$PGDATA/PG_VERSION" ]; then

        return 0

    fi

    return 1

}

initdb(){

    if [ -f "$PGDATA/PG_VERSION" ]; then

        echo $"Data directory is not empty!"

        echo

        script_result=1

    else

        echo -n $"Initializing database ... "

        if perform_initdb; then

            echo $"OK"

        else

            echo $"failed, see $PGLOG"

            script_result=1

        fi

        echo

    fi

}

upgrade(){

    # must see previous version in PG_VERSION

    if [ ! -f "$PGDATA/PG_VERSION" -o \

         x`cat "$PGDATA/PG_VERSION"` != x"$PREVMAJORVERSION" ]

    then

        echo

        echo $"Cannot upgrade because the database in $PGDATA is not of"

        echo $"compatible previous version $PREVMAJORVERSION."

        echo

        exit 1

    fi

    if [ ! -x "$PGENGINE/pg_upgrade" ]; then

        echo

        echo $"Please install the postgresql-upgrade RPM."

        echo

        exit 5

    fi

    # Set up log file for pg_upgrade

    rm -f "$PGUPLOG"

    touch "$PGUPLOG" || exit 1

    chown postgres:postgres "$PGUPLOG"

    chmod go-rwx "$PGUPLOG"

    [ -x /sbin/restorecon ] && /sbin/restorecon "$PGUPLOG"

    # Move old DB to PGDATAOLD

    PGDATAOLD="${PGDATA}-old"

    rm -rf "$PGDATAOLD"

    mv "$PGDATA" "$PGDATAOLD" || exit 1

    # Create configuration file for upgrade process

    HBA_CONF_BACKUP="$PGDATAOLD/pg_hba.conf.postgresql-setup.`date +%s`"

    HBA_CONF_BACKUP_EXISTS=0

    if [ ! -f $HBA_CONF_BACKUP ]; then

        mv "$PGDATAOLD/pg_hba.conf" "$HBA_CONF_BACKUP"

        HBA_CONF_BACKUP_EXISTS=1

        # For fluent upgrade 'postgres' user should be able to connect

        # to any database without password.  Temporarily, no other type

        # of connection is needed.

        echo "local all postgres ident" > "$PGDATAOLD/pg_hba.conf"

    fi

    echo -n $"Upgrading database: "

    # Create empty new-format database

    if perform_initdb; then

        # Do the upgrade

        $SU -l postgres -c "$PGENGINE/pg_upgrade \

                        '--old-bindir=$PREVPGENGINE' \

                        '--new-bindir=$PGENGINE' \

                        '--old-datadir=$PGDATAOLD' \

                        '--new-datadir=$PGDATA' \

                        --link \

                        '--old-port=$PGPORT' '--new-port=$PGPORT' \

                        --user=postgres \

                        $PGSETUP_PGUPGRADE_OPTIONS" \

                                >> "$PGUPLOG" 2>&1 < /dev/null

        if [ $? -ne 0 ]; then

            # pg_upgrade failed

            script_result=1

        fi

    else

        # initdb failed

        script_result=1

    fi

    # Move back the backed-up pg_hba.conf regardless of the script_result.

    if [ x$HBA_CONF_BACKUP_EXISTS = x1 ]; then

        mv -f "$HBA_CONF_BACKUP" "$PGDATAOLD/pg_hba.conf"

    fi

    if [ $script_result -eq 0 ]; then

        echo $"OK"

        echo

        echo $"The configuration files were replaced by default configuration."

        echo $"The previous configuration and data are stored in folder"

        echo $PGDATAOLD.

    else

        # Clean up after failure

        rm -rf "$PGDATA"

        mv "$PGDATAOLD" "$PGDATA"

        echo $"failed"

    fi

    echo

    echo $"See $PGUPLOG for details."

}

# See how we were called.

case "$1" in

    initdb)

        initdb

        ;;

    upgrade)

        upgrade

        ;;

    *)

        echo >&2 "$USAGE_STRING"

        exit 2

esac

exit $script_result