#!/bin/sh
#Copyright (c) 2017, Zane C. Bowers-Hadley
#All rights reserved.
#
#Redistribution and use in source and binary forms, with or without modification,
#are permitted provided that the following conditions are met:
#
#   * Redistributions of source code must retain the above copyright notice,
#    this list of conditions and the following disclaimer.
#   * Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
#THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
#ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
#WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
#IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
#INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
#BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
#DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
#LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
#OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
#THE POSSIBILITY OF SUCH DAMAGE.

# Location of optional config file.
CONFIG_FILE="/etc/snmp/postgres.config"

# Default DBuser is pgsql.  Be sure to set up the user in .pgpass for the user snmpd
# is running as.  You can either update the variable below, or add "DBuser=<username>"
# to the /etc/snmp/postgres.config file without quotes and replacing <username>.
DBuser=pgsql

# You may want to disable totalling for the postgres DB as that can make the total graphs artificially noisy.
# 1 = don't total stats for the DB postgres
# 0 = include postgres in the totals
# To set this to 0, you can either update the variable below, or add "ignorePG=0" to
# the /etc/snmp/postgres.config file (without quotes).
ignorePG=1;

# Hostname to connect to.  By default this is blank and check_postgres.ph will connect
# to the Unix socket.  You can either update the variable below, or add "DBhost=<hostname>"
# to the  /etc/snmp/postgres.config file without quotes and replacing <hostname>.
DBhost=""

# Load configuration from config file if the file exists.
if [ -f "$CONFIG_FILE" ]; then
    saved_IFS=$IFS
    IFS="="

    while read -r key value; do
        if [ "$key" = "DBuser" ]; then
            DBuser=$value
        elif [ "$key" = "ignorePG" ]; then
            ignorePG=$value
        elif [ "$key" = "DBhost" ]; then
            DBhost=$value
        fi
    done < $CONFIG_FILE

    IFS=$saved_IFS
fi

#make sure the paths are right for your system
cpg='/usr/bin/env check_postgres.pl'

cpg_command="$cpg -u $DBuser --action dbstats"
if [ "$DBhost" != "" ]; then
    cpg_command="$cpg_command -H $DBhost"
fi

$cpg_command | awk -F ' ' '

BEGIN{
	backends=0;
	commits=0;
	rollbacks=0;
	read=0;
	hit=0;
	idxscan=0;
	idxtupread=0;
	idxtupfetch=0;
	idxblksread=0;
	idxblkshit=0;
	seqscan=0;
	seqtupread=0;
	ret=0;
	fetch=0;
	ins=0;
	upd=0;
	del=0;
	db="";
    ignorePG='$ignorePG';
	toAdd=1;
}
{
	gsub(/dbname:/, "");
	gsub(/backends:/, "");
	gsub(/commits:/, "");
	gsub(/rollbacks:/, "");
	gsub(/idxscan:/, "");
	gsub(/idxtupread:/, "");
	gsub(/idxtupfetch:/, "");
	gsub(/idxblksread:/, "");
	gsub(/idxblkshit:/, "");
	gsub(/seqscan:/, "");
	gsub(/seqtupread:/, "");
	gsub(/ret:/, "");
	gsub(/fetch:/, "");
	gsub(/ins:/, "");
	gsub(/upd:/, "");
	gsub(/del:/, "");
	#must be processed last or they step on other gsub
	gsub(/read:/, "");
	gsub(/hit:/, "");

	if ( $18 == "postgres" ){
	  if ( ignorePG == 1 ){ toAdd=0 }
	}

	if ( toAdd == 1 ){
		backends=backends+$1;
		commits=commits+$2;
		rollbacks=rollbacks+$3;
		idxscan=idxscan+$6;
		idxtupread=idxtupread+$7;
		idxtupfetch=idxtupfetch+$8;
		idxblksread=idxblksread+$9;
		idxblkshit=idxblkshit+$10;
		seqscan=seqscan+$11;
		seqtupread=seqtupread+$12;
		ret=ret+$13;
		fetch=fetch+$14;
		ins=ins+$15;
		upd=upd+$16;
		del=del+$17;
		read=read+$4;
		hit=hit+$5;
	}

	db=db$1" "$2" "$3" "$4" "$5" "$6" "$7" "$8" "$9" "$10" "$11" "$12" "$13" "$14" "$15" "$16" "$17" "$18"\n";

	toAdd=1;
}
END{
	OFMT = "%.0f"
	print backends;
	print commits;
	print rollbacks;
	print read;
	print hit;
	print idxscan;
	print idxtupread;
	print idxtupfetch;
	print idxblksread;
	print idxblkshit;
	print seqscan;
	print seqtupread;
	print ret;
	print fetch;
	print ins;
	print upd;
	print del;
	print db;
}
'