Subversion Repositories ALCASAR

#!/bin/bash

#########################
## ALCASAR replication ##
##         list        ##
#########################
# The script is designed to list replicas of the ALCASAR instance.

# Constants
readonly ALCASAR_PWD="/root/ALCASAR-passwords.txt"
readonly SERVICES_PATH="/etc/systemd/system"

# Dynamically generated constants
DB_ROOT_PWD="$(grep db_root "$ALCASAR_PWD" | cut -d '=' -f 2-)"
readonly DB_ROOT_PWD

# Variables
query=""
attributes=""


check_args() {
        # Parse args
        args="$(getopt --longoptions "all,name:,help" --options "a,n:,h" -- "$@")"

        # Reset script args list
        eval set -- "$args"

        # Print help
        if [ $# -eq 1 ]
        then
                usage
                return 1
        fi

        # Loop over all args
        while true
        do
                case "$1" in
                        --all | -a)
                                query="SHOW ALL REPLICAS STATUS \\G"
                                break
                                ;;
                        --name | -n)
                                query="SHOW REPLICA '$2' STATUS \\G"
                                shift
                                break
                                ;;
                        --help | -h)
                                usage
                                return 2
                                ;;
                        --)
                                # End of args
                                break
                                ;;
                        *)
                                echo "error: unknown $1" >&2
                                return 3
                                break;;
                esac
                shift
        done
}

# Edit informations with more information (like real remote IP)
edit_output() {
        # Remove useless spaces
        attributes="$(echo "$attributes" | sed "s/^ *//")"

        # Loop over connections
        for conn_name in $(echo "$attributes" | grep "Connection_name" | cut -d ' ' -f 2-)
        do
                service_file="$SERVICES_PATH/replication-$conn_name.service"
                ip=""

                # Look for service file where remote IP is hardcoded (on secondary only)
                if ls "$service_file" &> /dev/null
                then
                        # Get IP from SSH tunnel service file
                        ip="$(grep "ExecStart" "$service_file" | sed -E "s/.*@(.*) *.*/\1/")"
                else
                        port="$(echo "$attributes" | grep -A5 "Connection_name: $conn_name" | grep "^Master_Port" | cut -d ' ' -f 2-)"

                        # Get IP from 'ss' established connections
                        pid="$(/usr/sbin/ss --tcp --processes | grep "$port.*sshd" | grep -oE "pid=[0-9]+" | cut -d '=' -f 2)"
                        # Skip if connection is closed
                        [ -z "$pid" ] && continue

                        # Find corresponding IP from PID
                        ip="$(/usr/sbin/ss --tcp --process | grep "$pid" | grep -v "127.0.0.1" | tr -s ' ' | cut -d ' ' -f 5 | cut -d ':' -f 1)"
                fi

                # Replace loopback address with the real remote IP
                attributes="$(echo "$attributes" | sed "/Connection_name: $conn_name/,/Master_Host/s/127.0.0.1/$ip/")"
        done
}

# Print script usage
usage() {
        echo "usage: $0 OPTIONS"
        echo
        echo "OPTIONS"
        echo "  --all"
        echo "          list all primary connections attributes"
        echo "  --name=NAME, -n NAME"
        echo "          list primary connection attributes"
        echo "  --help, -h"
        echo "          print this help message"
}


# Main
check_args "$@" || exit

# Execute the query
attributes="$(/usr/bin/mariadb --host="localhost" --user="root" --password="$DB_ROOT_PWD" --execute="$query")"
[ "$?" -ne 0 ] && exit 1

# Edit some information
edit_output

# Display data if any (in case there are no remotes)
[ -n "$attributes" ] && echo "$attributes"
exit 0