<?php
// Pluggable datasource for PHP Weathermap 0.9
// - return a live SNMP value

// doesn't work well with large values like interface counters (I think this is a rounding problem)
// - also it doesn't calculate rates. Just fetches a value.

// useful for absolute GAUGE-style values like DHCP Lease Counts, Wireless AP Associations, Firewall Sessions
// which you want to use to colour a NODE

// You could also fetch interface states from IF-MIB with it.

// TARGET snmp:public:hostname:1.3.6.1.4.1.3711.1.1:1.3.6.1.4.1.3711.1.2
// (that is, TARGET snmp:community:host:in_oid:out_oid

class WeatherMapDataSource_snmp extends WeatherMapDataSource
{
    function Init(&$map)
    {
        // We can keep a list of unresponsive nodes, so we can give up earlier
        $this->down_cache = array ();

        if (function_exists('snmpget')) {
            return (true);
        }
        wm_debug("SNMP DS: snmpget() not found. Do you have the PHP SNMP module?\n");

        return (false);
    }

    function Recognise($targetstring)
    {
        if (preg_match("/^snmp:([^:]+):([^:]+):([^:]+):([^:]+)$/", $targetstring,
            $matches)) {
            return true;
        } else {
            return false;
        }
    }

    function ReadData($targetstring, &$map, &$item)
    {
        $data[IN] = null;
        $data[OUT] = null;
        $data_time = 0;

        $timeout = 1000000;
        $retries = 2;
        $abort_count = 0;

        $in_result = null;
        $out_result = null;

        if ($map->get_hint('snmp_timeout') != '') {
            $timeout = intval($map->get_hint('snmp_timeout'));
            wm_debug('Timeout changed to ' . $timeout . " microseconds.\n");
        }

        if ($map->get_hint("snmp_abort_count") != '') {
            $abort_count = intval($map->get_hint("snmp_abort_count"));
            wm_debug("Will abort after $abort_count failures for a given host.\n");
        }

        if ($map->get_hint("snmp_retries") != '') {
            $retries = intval($map->get_hint("snmp_retries"));
            wm_debug("Number of retries changed to " . $retries . ".\n");
        }

        if (preg_match("/^snmp:([^:]+):([^:]+):([^:]+):([^:]+)$/", $targetstring,
            $matches)) {
            $community = $matches[1];
            $host = $matches[2];
            $in_oid = $matches[3];
            $out_oid = $matches[4];

            if (($abort_count == 0)
                || (($abort_count > 0) && (!isset($this->down_cache[$host])
                    || intval($this->down_cache[$host]) < $abort_count))) {
                if (function_exists("snmp_get_quick_print")) {
                    $was = snmp_get_quick_print();
                    snmp_set_quick_print(1);
                }

                if (function_exists("snmp_get_valueretrieval")) {
                    $was2 = snmp_get_valueretrieval();
                }

                if (function_exists('snmp_set_oid_output_format')) {
                    snmp_set_oid_output_format(SNMP_OID_OUTPUT_NUMERIC);
                }

                if (function_exists('snmp_set_valueretrieval')) {
                    snmp_set_valueretrieval(SNMP_VALUE_PLAIN);
                }

                if ($in_oid != '-') {
                    $in_result = snmpget($host, $community, $in_oid, $timeout, $retries);

                    if ($in_result !== FALSE) {
                        $data[IN] = floatval($in_result);
                        $item->add_hint("snmp_in_raw", $in_result);
                    } else {
                        $this->down_cache{$host}++;
                    }
                }

                if ($out_oid != '-') {
                    $out_result =
                        snmpget($host, $community, $out_oid, $timeout, $retries);

                    if ($out_result !== FALSE) {
// use floatval() here to force the output to be *some* kind of number
// just in case the stupid formatting stuff doesn't stop net-snmp returning 'down' instead of 2
                        $data[OUT] = floatval($out_result);
                        $item->add_hint("snmp_out_raw", $out_result);
                    } else {
                        $this->down_cache{$host}++;
                    }
                }

                wm_debug("SNMP ReadData: Got $in_result and $out_result\n");

                $data_time = time();

                if (function_exists("snmp_set_quick_print")) {
                    snmp_set_quick_print($was);
                }
            } else {
                wm_warn(
                    "SNMP for $host has reached $abort_count failures. Skipping. [WMSNMP01]");
            }
        }

        wm_debug( sprintf("SNMP ReadData: Returning (%s, %s, %s)\n",
		        string_or_null($data[IN]),
		        string_or_null($data[OUT]),
		        $data_time
        	));
        

        return (array (
            $data[IN],
            $data[OUT],
            $data_time
        ));
    }
}

// vim:ts=4:sw=4:
?>