#!/bin/sh
#
# Script Evobackup client
# See https://gitea.evolix.org/evolix/evobackup
#
# Author: Gregory Colpart <reg@evolix.fr>
# Contributors:
# Romain Dessort <rdessort@evolix.fr>
# Benoît Série <bserie@evolix.fr>
# Tristan Pilat <tpilat@evolix.fr>
# Victor Laborie <vlaborie@evolix.fr>
# Jérémy Lecour <jlecour@evolix.fr>
#
# Licence: AGPLv3
#
# /!\ DON'T FORGET TO SET "MAIL" and "SERVERS" VARIABLES

##### Configuration ###################################################

# email adress for notifications
MAIL=jdoe@example.com

# list of hosts (hostname or IP) and SSH port for Rsync
SERVERS="node0.backup.example.com:2XXX node1.backup.example.com:2XXX"

# timeout (in seconds) for the SSH test
SSH_CONNECT_TIMEOUT=60

## We use /home/backup : feel free to use your own dir
LOCAL_BACKUP_DIR="/home/backup"

# You can set "linux" or "bsd" manually or let it choose automatically
SYSTEM=$(uname | tr '[:upper:]' '[:lower:]')

##### SETUP AND FUNCTIONS #############################################

# shellcheck disable=SC2174
mkdir -p -m 700 ${LOCAL_BACKUP_DIR}

PATH=/sbin:/usr/sbin:/bin:/usr/bin:/usr/local/sbin:/usr/local/bin

# lang = C for english outputs
export LANGUAGE=C
export LANG=C

# Force umask
umask 077

# gzip binary, use pigz if available
GZIP_BIN=${$(command -v pigz):-$(command -v gzip)}

# Call test_server with "HOST:PORT" string
# It will return with 0 if the server is reachable.
# It will return with 1 and a message on stderr if not.
test_server() {
    item=$1
    # split HOST and PORT from the input string
    host=$(echo "${item}" | cut -d':' -f1)
    port=$(echo "${item}" | cut -d':' -f2)

    # Test if the server is accepting connections
    ssh -q -o "ConnectTimeout ${SSH_CONNECT_TIMEOUT}" "${host}" -p "${port}" -t "exit"
    # shellcheck disable=SC2181
    if [ $? = 0 ]; then
        # SSH connection is OK
        return 0
    else
        # SSH connection failed
        echo "Failed to connect to \`${item}' within ${SSH_CONNECT_TIMEOUT} seconds" >&2
        return 1
    fi
}
# Call pick_server with an optional positive integer to get the nth server in the list.
pick_server() {
    increment=${1:-0}
    list_length=$(echo "${SERVERS}" | wc -w)

    if [ "${increment}" -ge "${list_length}" ]; then
        # We've reached the end of the list
        echo "No more server available" >&2
        return 1
    fi

    # Extract the day of month, without leading 0 (which would give an octal based number) 
    today=$(date +%e)
    # A salt is useful to randomize the starting point in the list
    # but stay identical each time it's called for a server (based on hostname).
    salt=$(hostname | cksum | cut -d' ' -f1)
    # Pick an integer between 0 and the length of the SERVERS list
    # It changes each day
    item=$(( (today + salt + increment) % list_length ))
    # cut starts counting fields at 1, not 0.
    field=$(( item + 1 ))

    echo "${SERVERS}" | cut -d' ' -f${field}
}

# Verify other evobackup process and kill if needed
PIDFILE="/var/run/evobackup.pid"
if [ -e "${PIDFILE}" ]; then
    pid=$(cat "${PIDFILE}")
    # Killing the childs of evobackup.
    for ppid in $(ps h --ppid "${pid}" -o pid | tr -s '\n' ' '); do
        kill -9 "${ppid}";
    done
    # Then kill the main PID.
    kill -9 "${pid}"
    echo "$0 is still running (PID ${pid}). Process has been killed" >&2
fi
echo "$$" > ${PIDFILE}
# shellcheck disable=SC2064
trap "rm -f ${PIDFILE}" EXIT

##### LOCAL BACKUP ####################################################
## To enable a backup, set the variable to true
#######################################################################

# OpenLDAP with slapcat command
slapcatBackup=false
if $slapcatBackup; then
    slapcat -l ${LOCAL_BACKUP_DIR}/ldap.bak
fi

##### MySQL Section ###################################################
mysqlPort=3306
mysqlDefaultsExtraFile="--defaults-extra-file=/etc/mysql/debian.cnf"
mysqlCommonArgs="--opt --force --events --hex-blob"
mysqlDatabases=$(echo SHOW DATABASES \
    | mysql $mysqlDefaultsExtraFile -P $mysqlPort \
    | egrep -v "^(Database|information_schema|performance_schema|sys)"
)

# MySQL global compressed dump
mysqlGlobalDump=false
if $mysqlGlobalDump; then
    mysqldump \
        $mysqlDefaultsExtraFile \
        -P $mysqlPort \
        --all-databases \
        $mysqlCommonArgs \
        | $GZIP_BIN --best \
        > ${LOCAL_BACKUP_DIR}/backup/mysql.bak.gz
fi

# MySQL with data (.txt) separed from SQL structure (.sql)
mysqlDataStructure=false
if mysqlDataStructure; then
    for database in ${mysqlDatabases}; do
        mkdir -p -m 700 ${LOCAL_BACKUP_DIR}/mysqldump/${database}
        chown -RL mysql ${LOCAL_BACKUP_DIR}/mysqldump
        mysqldump \
            $mysqlDefaultsExtraFile \
            -P $mysqlPort \
            $mysqlCommonArgs \
            -Q \
            --skip-comments \
            --fields-enclosed-by='\"' \
            --fields-terminated-by=',' \
            -T ${LOCAL_BACKUP_DIR}/mysqldump/${database} \
            ${database}
    done
fi

# MySQL compressed dump for each database
mysqlEachDBDump=false
if $mysqlEachDBDump; then
    mysqlDatabases 3306
    mkdir -p -m 700 ${LOCAL_BACKUP_DIR}/mysqldump/
    for database in ${databases}; do
        mysqldump --defaults-extra-file=/etc/mysql/debian.cnf --force\
            -P 3306 --events --hex-blob $database \
            | $GZIP_BIN --best \
            > ${LOCAL_BACKUP_DIR}/mysqldump/${database}.sql.gz
    done
fi

# MySQL uncompressed dump for selected database(s)
mysqlSelectedDBDump=false
if $mysqlSelectedDBDump; then
    databases="exampledb1 exampledb2"
    for database in ${databases}; do
        mkdir -p -m 700 ${LOCAL_BACKUP_DIR}/mysqldump/${database}
        chown -RL mysql ${LOCAL_BACKUP_DIR}/mysqldump/
        mysqldump --defaults-extra-file=/etc/mysql/debian.cnf --force -Q \
            --opt --events --hex-blob --skip-comments -T \
            ${LOCAL_BACKUP_DIR}/mysqldump/${database} ${database}
    done
fi

## example for multiples MySQL instances
# mysqladminpasswd=$(grep -m1 'password = .*' /root/.my.cnf|cut -d" " -f3)
# grep -E "^port\s*=\s*\d*" /etc/mysql/my.cnf |while read instance; do
#     instance=$(echo "$instance"|awk '{ print $3 }')
#     if [ "$instance" != "3306" ]
#     then
#         mysqldump -P $instance --opt --all-databases --hex-blob -u mysqladmin -p$mysqladminpasswd > ${LOCAL_BACKUP_DIR}/mysql.$instance.bak
#     fi
# done

### PostgreSQL

## example with pg_dumpall (warning: you need space in ~postgres)
# su - postgres -c "pg_dumpall > ~/pg.dump.bak"
# mv ~postgres/pg.dump.bak ${LOCAL_BACKUP_DIR}/
## another method with gzip directly piped
# cd /var/lib/postgresql
# sudo -u postgres pg_dumpall | gzip > ${LOCAL_BACKUP_DIR}/pg.dump.bak.gz
# cd - > /dev/null

## example with all tables from MYBASE excepts TABLE1 and TABLE2
# pg_dump -p 5432 -h 127.0.0.1 -U USER --clean -F t --inserts -f ${LOCAL_BACKUP_DIR}/pg-backup.tar -t 'TABLE1' -t 'TABLE2' MYBASE

## example with only TABLE1 and TABLE2 from MYBASE
# pg_dump -p 5432 -h 127.0.0.1 -U USER --clean -F t --inserts -f ${LOCAL_BACKUP_DIR}/pg-backup.tar -T 'TABLE1' -T 'TABLE2' MYBASE

## MongoDB : example with mongodump
## don't forget to create use with read-only access
## > use admin
## > db.createUser( { user: "mongobackup", pwd: "PASS", roles: [ "backup", ] } )
# test -d ${LOCAL_BACKUP_DIR}/mongodump/ && rm -rf ${LOCAL_BACKUP_DIR}/mongodump/
# mkdir -p -m 700 ${LOCAL_BACKUP_DIR}/mongodump/
# mongodump --quiet -u mongobackup -pPASS -o ${LOCAL_BACKUP_DIR}/mongodump/
# if [ $? -ne 0 ]; then
#   echo "Error with mongodump!"
# fi

## Redis : example with copy .rdb file
# cp /var/lib/redis/dump.rdb ${LOCAL_BACKUP_DIR}/

## ElasticSearch, take a snapshot as a backup.
## Warning: You need to have a path.repo configured.
## See: https://wiki.evolix.org/HowtoElasticsearch#snapshots-et-sauvegardes
# curl -s -XDELETE "localhost:9200/_snapshot/snaprepo/snapshot.daily" -o /tmp/es_delete_snapshot.daily.log
# curl -s -XPUT "localhost:9200/_snapshot/snaprepo/snapshot.daily?wait_for_completion=true" -o /tmp/es_snapshot.daily.log
## Clustered version here
## It basically the same thing except that you need to check that NFS is mounted
# if ss | grep ':nfs' | grep -q 'ip\.add\.res\.s1' && ss | grep ':nfs' | grep -q 'ip\.add\.res\.s2'
# then
#     curl -s -XDELETE "localhost:9200/_snapshot/snaprepo/snapshot.daily" -o /tmp/es_delete_snapshot.daily.log
#     curl -s -XPUT "localhost:9200/_snapshot/snaprepo/snapshot.daily?wait_for_completion=true" -o /tmp/es_snapshot.daily.log
# else
#     echo 'Cannot make a snapshot of elasticsearch, at least one node is not mounting the repository.'
# fi
## If you need to keep older snapshot, for example the last 10 daily snapshots, replace the XDELETE and XPUT lines by :
# for snapshot in $(curl -s -XGET "localhost:9200/_snapshot/snaprepo/_all?pretty=true" | grep -Eo 'snapshot_[0-9]{4}-[0-9]{2}-[0-9]{2}' | head -n -10); do
#     curl -s -XDELETE "localhost:9200/_snapshot/snaprepo/${snapshot}" | grep -v -Fx '{"acknowledged":true}'
# done
# date=$(date +%F)
# curl -s -XPUT "localhost:9200/_snapshot/snaprepo/snapshot_${date}?wait_for_completion=true" -o /tmp/es_snapshot_${date}.log

## RabbitMQ : export config
#rabbitmqadmin export ${LOCAL_BACKUP_DIR}/rabbitmq.config >> /var/log/evobackup.log

# backup MegaCli config
#megacli -CfgSave -f ${LOCAL_BACKUP_DIR}/megacli_conf.dump -a0 >/dev/null

## Dump system and kernel versions
uname -a > ${LOCAL_BACKUP_DIR}/uname

## Dump network routes with mtr and traceroute (warning: could be long with aggressive firewalls)
for addr in 8.8.8.8 www.evolix.fr travaux.evolix.net; do
    mtr -r ${addr} > ${LOCAL_BACKUP_DIR}/mtr-${addr}
    traceroute -n ${addr} > ${LOCAL_BACKUP_DIR}/traceroute-${addr} 2>&1
done

## Dump process with ps
ps auwwx >${LOCAL_BACKUP_DIR}/ps.out

if [ "${SYSTEM}" = "linux" ]; then
    ## Dump network connections with ss
    ss -taupen > ${LOCAL_BACKUP_DIR}/netstat.out

    ## List Debian packages
    dpkg -l > ${LOCAL_BACKUP_DIR}/packages
    dpkg --get-selections > ${LOCAL_BACKUP_DIR}/packages.getselections
    apt-cache dumpavail > ${LOCAL_BACKUP_DIR}/packages.available

    ## Dump MBR / table partitions
    disks=$(find /dev/ -regex '/dev/\([sv]d[a-z]\|nvme[0-9]+n[0-9]+\)')
    for disk in ${disks}; do
        name=$(basename "${disk}")
        dd if="${disk}" of="${LOCAL_BACKUP_DIR}/MBR-${name}" bs=512 count=1 2>&1 | egrep -v "(records in|records out|512 bytes)"
        fdisk -l "${disk}" > "${LOCAL_BACKUP_DIR}/partitions-${name}"
    done
    cat ${LOCAL_BACKUP_DIR}/partitions-* > ${LOCAL_BACKUP_DIR}/partitions
else
    ## Dump network connections with netstat
    netstat -finet -atn > ${LOCAL_BACKUP_DIR}/netstat.out

    ## List OpenBSD packages
    pkg_info -m > ${LOCAL_BACKUP_DIR}/packages

    ## Dump MBR / table partitions
    ##disklabel sd0 > ${LOCAL_BACKUP_DIR}/partitions
fi

##### REMOTE BACKUP ###################################################

n=0
server=""
while :; do
    server=$(pick_server "${n}")
    test $? = 0 || exit 2

    if test_server "${server}"; then
        break
    else
        server=""
        n=$(( n + 1 ))
    fi
done

SSH_SERVER=$(echo "${server}" | cut -d':' -f1)
SSH_PORT=$(echo "${server}" | cut -d':' -f2)

HOSTNAME=$(hostname)

BEGINNING=$(/bin/date +"%d-%m-%Y ; %H:%M")

if [ "${SYSTEM}" = "linux" ]; then
    rep="/bin /boot /lib /opt /sbin /usr"
else
    rep="/bsd /bin /sbin /usr"
fi

# /!\ DO NOT USE COMMENTS in the rsync command /!\
# It breaks the command and destroys data, simply remove (or add) lines.

rsync -avzh --stats --delete --delete-excluded --force --ignore-errors --partial \
    --exclude "lost+found"                             \
    --exclude ".nfs.*"                                 \
    --exclude "/var/log"                               \
    --exclude "/var/log/evobackup*"                    \
    --exclude "/var/lib/mysql"                         \
    --exclude "/var/lib/postgres"                      \
    --exclude "/var/lib/postgresql"                    \
    --exclude "/var/lib/sympa"                         \
    --exclude "/var/lib/metche"                        \
    --exclude "/var/run"                               \
    --exclude "/var/lock"                              \
    --exclude "/var/state"                             \
    --exclude "/var/apt"                               \
    --exclude "/var/cache"                             \
    --exclude "/usr/src"                               \
    --exclude "/usr/doc"                               \
    --exclude "/usr/share/doc"                         \
    --exclude "/usr/obj"                               \
    --exclude "dev"                                    \
    --exclude "/var/spool/postfix"                     \
    --exclude "/var/lib/amavis/amavisd.sock"           \
    --exclude "/var/lib/munin/*tmp*"                   \
    --exclude "/var/lib/php5"                          \
    --exclude "/var/spool/squid"                       \
    --exclude "/var/lib/elasticsearch"                 \
    --exclude "/var/lib/amavis/tmp"                    \
    --exclude "/var/lib/clamav/*.tmp"                  \
    --exclude "/home/mysqltmp"                         \
    --exclude "/var/lib/php/sessions"                  \
        ${rep}                                         \
        /etc                                           \
        /root                                          \
        /var                                           \
        /home                                          \
        /srv                                           \
    -e "ssh -p ${SSH_PORT}"                            \
    "root@${SSH_SERVER}:/var/backup/"                  \
    | tail -30 >> /var/log/evobackup.log

END=$(/bin/date +"%d-%m-%Y ; %H:%M")

##### REPORTING #######################################################

echo "EvoBackup - ${HOSTNAME} - START ${BEGINNING} ON ${SSH_SERVER}" \
    >> /var/log/evobackup.log

echo "EvoBackup - ${HOSTNAME} - STOP ${END} ON ${SSH_SERVER}" \
    >> /var/log/evobackup.log

tail -10 /var/log/evobackup.log |                      \
    mail -s "[info] EvoBackup - Client ${HOSTNAME}"    \
    ${MAIL}