2015-04-19 16:46:59 +02:00

244 lines
7.3 KiB
PHP

<?php
/**
* @file
*
* This class parses cron rules and determines last execution time using least case integer comparison.
*/
class CronRule {
public $rule = NULL;
public $allow_shorthand = FALSE;
private static $ranges = array(
'minutes' => array(0, 59),
'hours' => array(0, 23),
'days' => array(1, 31),
'months' => array(1, 12),
'weekdays' => array(0, 6),
);
private $parsed_rule = array();
public $offset = 0;
/**
* Constructor
*/
function __construct($rule = NULL) {
$this->rule = $rule;
}
/**
* Expand interval from cronrule part
*
* @param $matches (e.g. 4-43/5+2)
* array of matches:
* [1] = lower
* [2] = upper
* [5] = step
* [7] = offset
*
* @return
* (string) comma-separated list of values
*/
function expandInterval($matches) {
$result = array();
$lower = $matches[1];
$upper = $matches[2];
$step = isset($matches[5]) ? $matches[5] : 1;
$offset = isset($matches[7]) ? $matches[7] : 0;
if ($step <= 0) return '';
$step = ($step > 0) ? $step : 1;
for ($i = $lower; $i <= $upper; $i+=$step) {
$result[] = ($i + $offset) % ($upper + 1);
}
return implode(',', $result);
}
/**
* Expand range from cronrule part
*
* @param $rule
* (string) cronrule part, e.g.: 1,2,3,4-43/5
* @param $max
* (string) boundaries, e.g.: 0-59
* @param $digits
* (int) number of digits of value (leading zeroes)
* @return
* (array) array of valid values
*/
function expandRange($rule, $type) {
$max = implode('-', self::$ranges[$type]);
$rule = str_replace("*", $max, $rule);
$rule = str_replace("@", $this->offset % (self::$ranges[$type][1] + 1), $rule);
$this->parsed_rule[$type] = $rule;
$rule = preg_replace_callback('!(\d+)-(\d+)((/(\d+))?(\+(\d+))?)?!', array($this, 'expandInterval'), $rule);
if (!preg_match('/([^0-9\,])/', $rule)) {
$rule = explode(',', $rule);
rsort($rule);
}
else {
$rule = array();
}
return $rule;
}
/**
* Pre process rule.
*
* @param array &$parts
*/
function preProcessRule(&$parts) {
// Allow JAN-DEC
$months = array(1 => 'jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul', 'aug', 'sep', 'oct', 'nov', 'dec');
$parts[3] = strtr(strtolower($parts[3]), array_flip($months));
// Allow SUN-SUN
$days = array('sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat');
$parts[4] = strtr(strtolower($parts[4]), array_flip($days));
$parts[4] = str_replace('7', '0', $parts[4]);
}
/**
* Post process rule
*
* @param array $intervals
*/
function postProcessRule(&$intervals) {
}
/**
* Generate regex rules
*
* @param $rule
* (string) cronrule, e.g: 1,2,3,4-43/5 * * * 2,5
* @return
* (array) date and time regular expression for mathing rule
*/
function getIntervals($rule = NULL) {
$parts = preg_split('/\s+/', isset($rule) ? $rule : $this->rule);
if ($this->allow_shorthand) $parts += array('*', '*', '*', '*', '*'); // Allow short rules by appending wildcards?
if (count($parts) != 5) return FALSE;
$this->preProcessRule($parts);
$intervals = array();
$intervals['minutes'] = $this->expandRange($parts[0], 'minutes');
if (empty($intervals['minutes'])) return FALSE;
$intervals['hours'] = $this->expandRange($parts[1], 'hours');
if (empty($intervals['hours'])) return FALSE;
$intervals['days'] = $this->expandRange($parts[2], 'days');
if (empty($intervals['days'])) return FALSE;
$intervals['months'] = $this->expandRange($parts[3], 'months');
if (empty($intervals['months'])) return FALSE;
$intervals['weekdays'] = $this->expandRange($parts[4], 'weekdays');
if (empty($intervals['weekdays'])) return FALSE;
$intervals['weekdays'] = array_flip($intervals['weekdays']);
$this->postProcessRule($intervals);
return $intervals;
}
/**
* Convert intervals back into crontab rule format
*/
function rebuildRule($intervals) {
$parts = array();
foreach ($intervals as $type => $interval) {
$parts[] = $this->parsed_rule[$type];
}
return implode(' ', $parts);
}
/**
* Parse rule. Run through parser expanding expression, and recombine into crontab syntax.
*/
function parseRule() {
return $this->rebuildRule($this->getIntervals());
}
/**
* Get last execution time of rule in unix timestamp format
*
* @param $time
* (int) time to use as relative time (default now)
* @return
* (int) unix timestamp of last execution time
*/
function getLastRan($time = NULL) {
// Current time round to last minute
if (!isset($time)) $time = time();
$time = floor($time / 60) * 60;
// Generate regular expressions from rule
$intervals = $this->getIntervals();
if ($intervals === FALSE) return FALSE;
// Get starting points
$start_year = date('Y', $time);
$end_year = $start_year - 28; // Go back max 28 years (leapyear * weekdays)
$start_month = date('n', $time);
$start_day = date('j', $time);
$start_hour = date('G', $time);
$start_minute = (int)date('i', $time);
// If both weekday and days are restricted, then use either or
// otherwise, use and ... when using or, we have to try out all the days in the month
// and not just to the ones restricted
$check_both = (count($intervals['days']) != 31 && count($intervals['weekdays']) != 7) ? FALSE : TRUE;
$days = $check_both ? $intervals['days'] : range(31, 1);
// Find last date and time this rule was run
for ($year = $start_year; $year > $end_year; $year--) {
foreach ($intervals['months'] as $month) {
if ($month < 1 || $month > 12) continue;
if ($year >= $start_year && $month > $start_month) continue;
foreach ($days as $day) {
if ($day < 1 || $day > 31) continue;
if ($year >= $start_year && $month >= $start_month && $day > $start_day) continue;
if (!checkdate($month, $day, $year)) continue;
// Check days and weekdays using and/or logic
$date_array = getdate(mktime(0, 0, 0, $month, $day, $year));
if ($check_both) {
if (!isset($intervals['weekdays'][$date_array['wday']])) continue;
}
else {
if (
!in_array($day, $intervals['days']) &&
!isset($intervals['weekdays'][$date_array['wday']])
) continue;
}
if ($day != $start_day || $month != $start_month || $year != $start_year) {
$start_hour = 23;
$start_minute = 59;
}
foreach ($intervals['hours'] as $hour) {
if ($hour < 0 || $hour > 23) continue;
if ($hour > $start_hour) continue;
if ($hour < $start_hour) $start_minute = 59;
foreach ($intervals['minutes'] as $minute) {
if ($minute < 0 || $minute > 59) continue;
if ($minute > $start_minute) continue;
break 5;
}
}
}
}
}
// Create unix timestamp from derived date+time
$time = mktime($hour, $minute, 0, $month, $day, $year);
return $time;
}
/**
* Check if a rule is valid
*/
function isValid($time = NULL) {
return $this->getLastRan($time) === FALSE ? FALSE : TRUE;
}
}