graph.php

<?php # vim: set filetype=php fdm=marker sw=4 ts=4 et : 
/*
 * Copyright (C) 2009  Bruno Prémont <bonbons AT linux-vserver.org>
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation; only version 2 of the License is applicable.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

//error_reporting(E_ALL | E_NOTICE | E_WARNING);

if (isset($_GET['type_instance']) && $_GET['type_instance'] == '_') { unset($_GET['type_instance']); }
if (isset($_GET['plugin_instance']) && $_GET['plugin_instance'] == '_') { unset($_GET['plugin_instance']); }
require('etc/config.graph.php');
require('lib/functions.graph.php');
require('etc/definitions.php');
require 'lib/common.php';

function makeTextBlock($text, $fontfile, $fontsize, $width) {
    // TODO: handle explicit line-break!
    $words = explode(' ', $text);
    $lines = array($words[0]);
    $currentLine = 0;
    array_shift($words);
    foreach ($words as $word) {
        $lineSize = imagettfbbox($fontsize, 0, $fontfile, $lines[$currentLine] . ' ' . $word);
        if($lineSize[2] - $lineSize[0] < $width) {
            $lines[$currentLine] .= ' ' . $word;
        } else {
            $currentLine++;
            $lines[$currentLine] = $word;
        }
    }
    //error_log(sprintf('Handles message "%s", %d words => %d/%d lines', $text, count($words), $currentLine, count($lines)));
    return implode("\n", $lines);
}

/**
 * No RRD files found that could match request
 * @code HTTP error code
 * @code_msg Short text description of HTTP error code
 * @title Title for fake RRD graph
 * @msg Complete error message to display in place of graph content
 */
function error($code, $code_msg, $title, $msg) {
    global $config;
    header(sprintf("HTTP/1.0 %d %s", $code, $code_msg));
    header("Pragma: no-cache");
    header("Expires: Mon, 01 Jan 2008 00:00:00 CET");
    header("Content-Type: image/png");
    $w = $config['rrd_width']+81+16;
    $h = $config['rrd_height']+79;

    $png     = imagecreate($w, $h);

    $c_bkgnd = imagecolorallocate($png, 255, 255, 255);
    $c_fgnd  = imagecolorallocate($png, 255, 255, 255);
    $c_blt   = imagecolorallocate($png, 208, 208, 208);
    $c_brb   = imagecolorallocate($png, 160, 160, 160);
    $c_grln  = imagecolorallocate($png, 114, 114, 114);
    $c_grarr = imagecolorallocate($png, 128,  32,  32);
    $c_txt   = imagecolorallocate($png, 0, 0, 0);
    $c_etxt  = imagecolorallocate($png, 64, 0, 0);
    if (function_exists('imageantialias'))
        imageantialias($png, true);
    //imagefilledrectangle($png, 0,   0, $w, $h, $c_bkgnd);
    imagefilledrectangle($png, 51, 33, $w-31, $h-47, $c_fgnd);
    imageline($png,  51,  30,  51, $h-43, $c_grln);
    imageline($png,  48, $h-46, $w-28, $h-46, $c_grln);
    imagefilledpolygon($png, array(49, 30,    51, 26,    53, 30), 3, $c_grarr);
    imagefilledpolygon($png, array($w-28, $h-48,  $w-24, $h-46,  $w-28, $h-44), 3, $c_grarr);
    //	imageline($png,    0,    0,   $w,    0, $c_blt);
    //	imageline($png,    0,    1,   $w,    1, $c_blt);
    //	imageline($png,    0,    0,    0,   $h, $c_blt);
    //	imageline($png,    1,    0,    1,   $h, $c_blt);
    //	imageline($png, $w-1,    0, $w-1,   $h, $c_brb);
    //	imageline($png, $w-2,    1, $w-2,   $h, $c_brb);
    //	imageline($png,    1, $h-2,   $w, $h-2, $c_brb);
    //	imageline($png,    0, $h-1,   $w, $h-1, $c_brb);
    imagestring($png, 4, ceil(($w-strlen($title)*imagefontwidth(4)) / 2), 10, $title, $c_txt);
    if (isset($_GET['debug'])) {
        imagestring($png, 5, 60, 35, sprintf('%s [%d]', $code_msg, $code), $c_etxt);
    }
    if (function_exists('imagettfbbox') && is_file($config['error_font'])) {
        // Detailled error message
        $fmt_msg = makeTextBlock($msg, $config['error_font'], 10, $w-86);
        $fmtbox  = imagettfbbox(12, 0, $config['error_font'], $fmt_msg);
        imagettftext($png, 10, 0, 55, 35+3+imagefontwidth(5)-$fmtbox[7]+$fmtbox[1], $c_txt, $config['error_font'], $fmt_msg);
    } else {
        imagestring($png, 4, 53, 35+6+imagefontwidth(5), $msg, $c_txt);
    }
    imagepng($png);
    imagedestroy($png);

}

/**
 * No RRD files found that could match request
 */
function error404($title, $msg) {
    return error(404, "Not found", $title, $msg);
}

/**
 * Incomplete / invalid request
 */
function error400($title, $msg) {
    return error(400, "Bad request", $title, $msg);
}

/**
 * Incomplete / invalid request
 */
function error500($title, $msg) {
    return error(500, "Internal error", $title, $msg);
}

// Process input arguments
$collectd_source  = read_var('collectd_source', $_GET, null);
if (is_null($collectd_source))
    return error400("?/?-?/?", "Missing collectd_source name");
else if (!is_string($collectd_source))
    return error400("?/?-?/?", "Expecting exactly 1 collectd_source name");
else if (strlen($collectd_source) == 0)
    return error400("?/?-?/?", "Collectd source name may not be blank");

$host     = read_var('host', $_GET, null);
if (is_null($host))
    return error400("?/?-?/?", "Missing host name");
else if (!is_string($host))
    return error400("?/?-?/?", "Expecting exactly 1 host name");
else if (strlen($host) == 0)
    return error400("?/?-?/?", "Host name may not be blank");

$althost     = read_var('althost', $_GET, null);
if (is_null($althost))
    $althost = "";
else if (!is_string($althost))
    return error400("?/?-?/?", "Expecting exactly 1 alt host name");

$plugin   = read_var('plugin', $_GET, null);
if (is_null($plugin))
    return error400($host.'/?-?/?', "Missing plugin name");
else if (!is_string($plugin))
    return error400($host.'/?-?/?', "Plugin name must be a string");
else if (strlen($plugin) == 0)
    return error400($host.'/?-?/?', "Plugin name may not be blank");

$pinst    = read_var('plugin_instance', $_GET, '');
if (!is_string($pinst))
    return error400($host.'/'.$plugin.'-?/?', "Plugin instance name must be a string");

$type     = read_var('type', $_GET, '');
if (is_null($type))
    return error400($host.'/'.$plugin.(strlen($pinst) ? '-'.$pinst : '').'/?', "Missing type name");
else if (!is_string($type))
    return error400($host.'/'.$plugin.(strlen($pinst) ? '-'.$pinst : '').'/?', "Type name must be a string");
else if (strlen($type) == 0)
    return error400($host.'/'.$plugin.(strlen($pinst) ? '-'.$pinst : '').'/?', "Type name may not be blank");

$tinst    = read_var('type_instance', $_GET, '');

$graph_identifier = $host.'/'.$plugin.(strlen($pinst) ? '-'.$pinst : '').'/'.$type.(strlen($tinst) ? '-'.$tinst : '-*');

$timespan = read_var('timespan', $_GET, $config['timespan'][0]['name']);
$timespan_ok = false;
foreach ($config['timespan'] as &$ts)
    if ($ts['name'] == $timespan)
        $timespan_ok = true;
if (!$timespan_ok)
    return error400($graph_identifier, "Unknown timespan requested");

$begin = read_var('begin', $_GET, -86400);
$end = read_var('end', $_GET, null);

$xcenter = $begin < 0 ? $xcenter = time() + ($begin / 2) : $xcenter = $end - (($end - $begin) / 2);
$xcenter = intval($xcenter);

$xconfig = array();
if(is_numeric($end) and $begin > 0 and  $end - $begin > 2160000 and $end - $begin < 12960000)
{
    if($end - $begin < 12960000 - (86400*7))
        $xconfig = array('--x-grid', 'DAY:1:DAY:7:DAY:7:0:%d/%m');
    else
        $xconfig = array('--x-grid', 'DAY:1:DAY:7:DAY:14:0:%d/%m');
}

$logscale   = (boolean)read_var('logarithmic', $_GET, false);
$tinylegend = (boolean)read_var('tinylegend', $_GET, false);
$zero 		= (boolean)read_var('zero', $_GET, false);

// Check that at least 1 RRD exists for the specified request
$all_tinst = collectd_list_types($collectd_source, $host, $plugin, $pinst, $type);
if (count($all_tinst) == 0)
    return error404($graph_identifier, "No rrd file found for graphing : $host, $plugin, $pinst, $type");

// Now that we are read, do the bulk work
load_graph_definitions($logscale, $tinylegend, $zero);

$pinst = strlen($pinst) == 0 ? null : $pinst;
$tinst = strlen($tinst) == 0 ? null : $tinst;

$opts  = array();
$opts['timespan'] = $timespan;
if ($logscale)
    $opts['logarithmic'] = 1;
if ($tinylegend)
    $opts['tinylegend']  = 1;
if ($zero)
    $opts['zero']  = 1;
if ($althost)
    $opts['althost']  = $althost;

$rrd_cmd = false;
if (isset($MetaGraphDefs[$type])) {
    if ($type == '_') {
        $rrd_cmd = $MetaGraphDefs[$type]($collectd_source, $host, $plugin, $pinst, $type, $all_tinst, $opts);
    } else {
        $rrd_cmd = $MetaGraphDefs[$type]($collectd_source, $host, $plugin, $pinst, $type, $tinst, $opts);
    }
} else if (isset($GraphDefs[$type])) {
    $rrd_cmd = collectd_draw_generic($collectd_source, $host, $plugin, $pinst, $type, $tinst, $opts);
} else {
    $rrd_cmd = collectd_draw_rrd($collectd_source, $host, $plugin, $pinst, $type, $tinst, $opts);
}
$rrd_cmd[] = 'VRULE:'.$GLOBALS['xcenter'].'#888888:'.date("Y/m/d H\\\\:i\\\\:s",$GLOBALS['xcenter']).'\l:dashes';
$rrd_cmd = array_merge($rrd_cmd,$xconfig);
$rrd_cmd[] = "-m";
$rrd_cmd[] = "1";
if (isset($_GET['debug'])) {
    header('Content-Type: text/plain; charset=utf-8');
    printf("Would have executed on '%s' :\n%s\n", $collectd_source, is_array($rrd_cmd) ? "'$rrdtool' 'graph' '-' '".implode("' '", $rrd_cmd )."'" : $rrd_cmd);
    return 0;
}
if(!$rrd_cmd) {
    return error500($graph_identifier, "Failed to tell RRD how to generate the graph");
}

################################################################
# The following commented code allows to flush rrdcached before
# drawing.
# However, when using pw_rrd_graphonly with jsonrpc, rrdcached
# will automatically be flushed.
# So this code is useless here.
# We leave it only in case somebody needs it.
#
#    /* Get list of files to flush */
#    $files = array();
#    foreach ($rrd_cmd as $l) {
#        if(0 < preg_match("/^DEF:[^=:]+=([^:]+):/", $l, $m)) {
#            $files[$m[1]] = 1;
#        }
#    }
#
#    /* Flush the rrds */
#    putenv('http_proxy');
#    putenv('https_proxy');
#    $json = json_encode(array(
#                "jsonrpc" => "2.0",
#                "method" => "pw_rrd_flush",
#                "params" => array_keys($files),
#                "id" => 0)
#            );
#    $ra = jsonrpc_query($collectd_source, $json);
#
#    $ret = array();
#    if(!(isset($ra[0]) && isset($ra[1]))) { return($ret); }
################################################################

/* Graph the rrds */
$json = json_encode(array(
            "jsonrpc" => "2.0",
            "method" => "pw_rrd_graphonly",
            "params" => $rrd_cmd,
            "id" => 0)
        );
$ra = jsonrpc_query($collectd_source, $json);

$ret = array();
if(!(isset($ra[0]) && isset($ra[1]))) {
    return error500($graph_identifier, "Collectd server failed to answer the request for a graph");
}
$r = $ra[0];
if(!isset($r["image"])) {
    return error404($graph_identifier, "Collectd server failed to send a graph");
}

if (isset($_GET['download'])) {
    header("Pragma: public");
    header("Expires: 0");
    header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
    header("Cache-Control: private",false);
    header("Content-Type: application/octet-stream");
    header("Content-Disposition: attachment; filename=\"graph.png\";" );
    header("Content-Transfer-Encoding: binary"); 
} else {
    header('Content-Type: image/png');
}
header('Cache-Control: max-age=60');
echo base64_decode($r["image"]);


################################################################
# This is how we generated the graphs before.
# We keep it in case somebody needs it one day...
#
#    $cmd = "'$rrdtool' 'graph' '-' '".implode("' '", $rrd_cmd )."'";
#    echo `$cmd`;
################################################################

    exit();

?>