Cron - Code Metrics - Inspection of "code quality improvement" - poliander/cron - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( 3d559d...4b8df0 )

by René

created 2016-06-11 14:58 UTC

Cron C

↳ Parent: Project

Complexity

Total Complexity

Size/Duplication

Total Lines	434
Duplicated Lines	1.38 %

Coupling/Cohesion

Components	1
Dependencies	0

Importance

Changes	14
Bugs	0	Features	0

Metric	Value
wmc	60
c	14
b	0
f	0
lcom	1
cbo	0
dl	6
loc	434
rs	6.0975

14 Methods

Rating	Name	Duplication	Size	Complexity
A	__construct()	0	5	1
A	setExpression()	0	7	1
A	setTimeZone()	0	5	1
B	isMatching()	0	31	6
A	isValid()	0	14	3
C	getNext()	0	61	14
A	parse()	0	16	3
A	parseSegment()	0	15	4
A	parseElement()	0	20	4
A	parseRange()	0	12	3
B	parseValues()	6	14	8
B	parseStepping()	0	20	5
A	validateRange()	0	12	3
A	validateValue()	0	11	4

How to fix Duplicated Code Complexity

Duplicated Code

Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.

Common duplication problems, and corresponding solutions are:

If you have the same expression in different places: Extract expression to a method
If you have the same method in different sub-classes: Extract method, and pull up field to the parent class
If you have the same code in unrelated classes: Consider extracting the code to a new class, and injecting that class

Complex Class

Tip: Before tackling complexity, make sure that you eliminate any duplication first. This often can reduce the size of classes significantly.

Complex classes like Cron often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.

Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.

While breaking up the class, it is a good idea to analyze how other classes use Cron, and based on these observations, apply Extract Interface, too.

<?php

/**
 * Cron expression parser and validator
 *
 * @author René Pollesch
 */
class Cron
namespace YourVendor;

class YourClass { }
{
    /**
     * Weekday look-up table
     *
     * @var array
     */
    protected static $weekdays = [
        'sun' => 0,
        'mon' => 1,
        'tue' => 2,
        'wed' => 3,
        'thu' => 4,
        'fri' => 5,
        'sat' => 6
    ];

    /**
     * Month name look-up table
     *
     * @var array
     */
    protected static $months = [
        'jan' => 1,
        'feb' => 2,
        'mar' => 3,
        'apr' => 4,
        'may' => 5,
        'jun' => 6,
        'jul' => 7,
        'aug' => 8,
        'sep' => 9,
        'oct' => 10,
        'nov' => 11,
        'dec' => 12
    ];

    /**
     * Value boundaries
     *
     * @var array
     */
    protected static $boundaries = [
        0 => [
            'min' => 0,
            'max' => 59
        ],
        1 => [
            'min' => 0,
            'max' => 23
        ],
        2 => [
            'min' => 1,
            'max' => 31
        ],
        3 => [
            'min' => 1,
            'max' => 12
        ],
        4 => [
            'min' => 0,
            'max' => 7
        ]
    ];

    /**
     * Cron expression
     *
     * @var string
     */
    protected $expression;

    /**
     * Time zone
     *
     * @var \DateTimeZone
     */
    protected $timeZone;

    /**
     * Matching register
     *
     * @var array|null
     */
    protected $register;

    /**
     * Class constructor sets cron expression property
     *
     * @param string $expression cron expression
     * @param \DateTimeZone $timeZone
     */
    public function __construct($expression = '* * * * *', \DateTimeZone $timeZone = null)
    {
        $this->setExpression($expression);
        $this->setTimeZone($timeZone);
    }

    /**
     * Set expression
     *
     * @param string $expression
     * @return self
     */
    public function setExpression($expression)
    {
        $this->expression = trim((string)$expression);
        $this->register = null;

        return $this;
    }

    /**
     * Set time zone
     *
     * @param \DateTimeZone $timeZone
     * @return self
     */
    public function setTimeZone(\DateTimeZone $timeZone = null)
    {
        $this->timeZone = $timeZone;
        return $this;
    }

    /**
     * Parse and validate cron expression
     *
     * @return bool true if expression is valid, or false on error
     */
    public function isValid()
    {
        $result = true;

        if ($this->register === null) {
            try {
                $this->register = $this->parse();
            } catch (\Exception $e) {
                $result = false;
            }
        }

        return $result;
    }

    /**
     * Match current or given date/time against cron expression
     *
     * @param mixed $dtime \DateTime object, timestamp or null
     * @return bool
     */
    public function isMatching($dtime = null)
    {
        if ($dtime instanceof \DateTime) {
            $dtime->setTimezone($this->timeZone);
        } else {
            $dt = new \DateTime('now', $this->timeZone);

            if ((int)$dtime > 0) {
                $dt->setTimestamp($dtime);
            }

            $dtime = $dt;
        }

        $segments = sscanf($dtime->format('i G j n w'), '%d %d %d %d %d');

        try {
            $result = true;

            foreach ($this->parse() as $i => $item) {
                if (isset($item[(int)$segments[$i]]) === false) {
                    $result = false;
                    break;
                }
            }
        } catch (\Exception $e) {
            $result = false;
        }

        return $result;
    }

    /**
     * Calculate next matching timestamp
     *
     * @param mixed $dtime \DateTime object, timestamp or null
     * @return int|bool next matching timestamp, or false on error
     */
    public function getNext($dtime = null)
    {
        $result = false;

        if ($this->isValid()) {
            if ($dtime instanceof \DateTime) {
                $timestamp = $dtime->getTimestamp();
            } elseif ((int)$dtime > 0) {
                $timestamp = $dtime;
            } else {
                $timestamp = time();
            }

            $dt = new \DateTime('now', $this->timeZone);
            $dt->setTimestamp(ceil($timestamp / 60) * 60);

            list($pday, $pmonth, $pyear, $phour) = sscanf(
                $dt->format('j n Y G'),
                '%d %d %d %d'
            );

            while ($result === false) {
                list($minute, $hour, $day, $month, $year, $weekday) = sscanf(
                    $dt->format('i G j n Y w'),
                    '%d %d %d %d %d %d'
                );

                if ($pyear !== $year) {
                    $dt->setDate($year, 1, 1);
                    $dt->setTime(0, 0);
                } elseif ($pmonth !== $month) {
                    $dt->setDate($year, $month, 1);
                    $dt->setTime(0, 0);
                } elseif ($pday !== $day) {
                    $dt->setTime(0, 0);
                } elseif ($phour !== $hour) {
                    $dt->setTime($hour, 0);
                }

                list($pday, $pmonth, $pyear, $phour) = [$day, $month, $year, $hour];

                if (isset($this->register[3][$month]) === false) {
                    $dt->modify('+1 month');
                    continue;
                } elseif (false === (isset($this->register[2][$day]) && isset($this->register[4][$weekday]))) {
                    $dt->modify('+1 day');
                    continue;
                } elseif (isset($this->register[1][$hour]) === false) {
                    $dt->modify('+1 hour');
                    continue;
                } elseif (isset($this->register[0][$minute]) === false) {
                    $dt->modify('+1 minute');
                    continue;
                }

                $result = $dt->getTimestamp();
            }
        }

        return $result;
    }

    /**
     * Parse whole cron expression
     *
     * @return array
     * @throws \Exception
     */
    private function parse()
    {
        $register = [];

        if (sizeof($segments = preg_split('/\s+/', $this->expression)) === 5) {
            foreach ($segments as $index => $segment) {
                $this->parseSegment($index, $register, $segment);
            }

            $register[4][0] = isset($register[4][7]);
        } else {
            throw new \Exception('invalid number of segments');
        }

        return $register;
    }

    /**
     * Parse one segment of a cron expression
     *
     * @param int $index
     * @param string $segment
     * @param array $register
     * @throws \Exception
     */
    private function parseSegment($index, array &$register, $segment)
    {
        $strv = [false, false, false, self::$months, self::$weekdays];

        // month names, weekdays
        if ($strv[$index] !== false && isset($strv[$index][strtolower($segment)])) {
            // cannot be used with lists or ranges, see crontab(5) man page
            $register[$index][$strv[$index][strtolower($segment)]] = true;
        } else {
            // split up current segment into single elements, e.g. "1,5-7,*/2" => [ "1", "5-7", "*/2" ]
            foreach (explode(',', $segment) as $element) {
                $this->parseElement($index, $register, $element);
            }
        }
    }

    /**
     * @param int $index
     * @param string $element
     * @param array $register
     * @throws \Exception
     */
    private function parseElement($index, array &$register, $element)
    {
        if (false === strpos($element, '/')) {
            $stepping = 1;
        } else {
            $stepping = $this->parseStepping($index, $element);
        }

        if (is_numeric($element)) {
            $this->validateValue($index, $element);

            if ($stepping !== 1) {
                throw new \Exception('invalid combination of value and stepping notation');
            }

            $register[$index][intval($element)] = true;
        } else {
            $this->parseRange($index, $register, $element, $stepping);
        }
    }

    /**
     * Parse range of values, e.g. "5-10"
     *
     * @param int $index
     * @param array $register
     * @param string $range
     * @param int $stepping
     * @throws \Exception
     */
    private function parseRange($index, array &$register, $range, $stepping)
    {
        if ($range === '*') {
            $range = [self::$boundaries[$index]['min'], self::$boundaries[$index]['max']];
        } elseif (strpos($range, '-') !== false) {
            $range = $this->validateRange($index, explode('-', $range));
        } else {
            throw new \Exception('failed to parse list segment');
        }

        $this->parseValues($index, $register, $range, $stepping);
    }

    /**
     * @param int $index
     * @param array $register
     * @param array $range
     * @param int $stepping
     */
    private function parseValues($index, array &$register, array $range, $stepping)
    {
        for ($i = self::$boundaries[$index]['min']; $i <= self::$boundaries[$index]['max']; $i++) {
            if (($i - $range[0]) % $stepping === 0) {
                if ($range[0] < $range[1]) {
                    if ($i >= $range[0] && $i <= $range[1]) {

                        $register[$index][$i] = true;
                    }
                } elseif ($i >= $range[0] || $i <= $range[1]) {

                    $register[$index][$i] = true;
                }
            }
        }
    }

    /**
     * Parse stepping notation, e.g. "/2"
     *
     * @param int $index
     * @param string $element
     * @return int
     * @throws \Exception
     */
    private function parseStepping($index, &$element)
    {
        if (sizeof($segments = explode('/', $element)) === 2) {
            $element = $segments[0];

            if (is_numeric($segments[1])) {
                if ($segments[1] > 0 && $segments[1] <= self::$boundaries[$index]['max']) {
                    $stepping = $segments[1];
                } else {
                    throw new \Exception('stepping value out of allowed range');
                }
            } else {
                throw new \Exception('non-numeric stepping notation');
            }
        } else {
            throw new \Exception('invalid stepping notation');
        }

        return $stepping;
    }

    /**
     * Validate whether a given range of values exceeds allowed value boundaries
     *
     * @param int $index
     * @param array $range
     * @return array
     * @throws \Exception
     */
    private function validateRange($index, array $range)
    {
        if (sizeof($range) !== 2) {
            throw new \Exception('invalid range notation');
        }

        foreach ($range as $value) {
            $this->validateValue($index, $value);
        }

        return $range;
    }

    /**
     * @param int $index
     * @param int $value
     * @throws \Exception
     */
    private function validateValue($index, $value)
    {
        if (is_numeric($value)) {
            if (intval($value) < self::$boundaries[$index]['min'] ||
                intval($value) > self::$boundaries[$index]['max']) {
                throw new \Exception('value boundary exceeded');
            }
        } else {
            throw new \Exception('non-integer value');
        }
    }
}


1		<?php
2
3		/**
4		* Cron expression parser and validator
5		*
6		* @author René Pollesch
7		*/
8		class Cron
		0 ignored issues – show Coding Style Compatibility introduced 2016-06-11 10:57 UTC by Report Bug Copy Issue Report PSR1 recommends that each class must be in a namespace of at least one level to avoid collisions. You can fix this by adding a namespace to your class: namespace YourVendor; class YourClass { } When choosing a vendor namespace, try to pick something that is not too generic to avoid conflicts with other libraries. Loading history...
9		{
10		/**
11		* Weekday look-up table
12		*
13		* @var array
14		*/
15		protected static $weekdays = [
16		'sun' => 0,
17		'mon' => 1,
18		'tue' => 2,
19		'wed' => 3,
20		'thu' => 4,
21		'fri' => 5,
22		'sat' => 6
23		];
24
25		/**
26		* Month name look-up table
27		*
28		* @var array
29		*/
30		protected static $months = [
31		'jan' => 1,
32		'feb' => 2,
33		'mar' => 3,
34		'apr' => 4,
35		'may' => 5,
36		'jun' => 6,
37		'jul' => 7,
38		'aug' => 8,
39		'sep' => 9,
40		'oct' => 10,
41		'nov' => 11,
42		'dec' => 12
43		];
44
45		/**
46		* Value boundaries
47		*
48		* @var array
49		*/
50		protected static $boundaries = [
51		0 => [
52		'min' => 0,
53		'max' => 59
54		],
55		1 => [
56		'min' => 0,
57		'max' => 23
58		],
59		2 => [
60		'min' => 1,
61		'max' => 31
62		],
63		3 => [
64		'min' => 1,
65		'max' => 12
66		],
67		4 => [
68		'min' => 0,
69		'max' => 7
70		]
71		];
72
73		/**
74		* Cron expression
75		*
76		* @var string
77		*/
78		protected $expression;
79
80		/**
81		* Time zone
82		*
83		* @var \DateTimeZone
84		*/
85		protected $timeZone;
86
87		/**
88		* Matching register
89		*
90		* @var array\|null
91		*/
92		protected $register;
93
94		/**
95		* Class constructor sets cron expression property
96		*
97		* @param string $expression cron expression
98		* @param \DateTimeZone $timeZone
99		*/
100		public function __construct($expression = '* * * * *', \DateTimeZone $timeZone = null)
101		{
102		$this->setExpression($expression);
103		$this->setTimeZone($timeZone);
104		}
105
106		/**
107		* Set expression
108		*
109		* @param string $expression
110		* @return self
111		*/
112		public function setExpression($expression)
113		{
114		$this->expression = trim((string)$expression);
115		$this->register = null;
116
117		return $this;
118		}
119
120		/**
121		* Set time zone
122		*
123		* @param \DateTimeZone $timeZone
124		* @return self
125		*/
126		public function setTimeZone(\DateTimeZone $timeZone = null)
127		{
128		$this->timeZone = $timeZone;
129		return $this;
130		}
131
132		/**
133		* Parse and validate cron expression
134		*
135		* @return bool true if expression is valid, or false on error
136		*/
137		public function isValid()
138		{
139		$result = true;
140
141		if ($this->register === null) {
142		try {
143		$this->register = $this->parse();
144		} catch (\Exception $e) {
145		$result = false;
146		}
147		}
148
149		return $result;
150		}
151
152		/**
153		* Match current or given date/time against cron expression
154		*
155		* @param mixed $dtime \DateTime object, timestamp or null
156		* @return bool
157		*/
158		public function isMatching($dtime = null)
159		{
160		if ($dtime instanceof \DateTime) {
161		$dtime->setTimezone($this->timeZone);
162		} else {
163		$dt = new \DateTime('now', $this->timeZone);
164
165		if ((int)$dtime > 0) {
166		$dt->setTimestamp($dtime);
167		}
168
169		$dtime = $dt;
170		}
171
172		$segments = sscanf($dtime->format('i G j n w'), '%d %d %d %d %d');
173
174		try {
175		$result = true;
176
177		foreach ($this->parse() as $i => $item) {
178		if (isset($item[(int)$segments[$i]]) === false) {
179		$result = false;
180		break;
181		}
182		}
183		} catch (\Exception $e) {
184		$result = false;
185		}
186
187		return $result;
188		}
189
190		/**
191		* Calculate next matching timestamp
192		*
193		* @param mixed $dtime \DateTime object, timestamp or null
194		* @return int\|bool next matching timestamp, or false on error
195		*/
196		public function getNext($dtime = null)
197		{
198		$result = false;
199
200		if ($this->isValid()) {
201		if ($dtime instanceof \DateTime) {
202		$timestamp = $dtime->getTimestamp();
203		} elseif ((int)$dtime > 0) {
204		$timestamp = $dtime;
205		} else {
206		$timestamp = time();
207		}
208
209		$dt = new \DateTime('now', $this->timeZone);
210		$dt->setTimestamp(ceil($timestamp / 60) * 60);
211
212		list($pday, $pmonth, $pyear, $phour) = sscanf(
213		$dt->format('j n Y G'),
214		'%d %d %d %d'
215		);
216
217		while ($result === false) {
218		list($minute, $hour, $day, $month, $year, $weekday) = sscanf(
219		$dt->format('i G j n Y w'),
220		'%d %d %d %d %d %d'
221		);
222
223		if ($pyear !== $year) {
224		$dt->setDate($year, 1, 1);
225		$dt->setTime(0, 0);
226		} elseif ($pmonth !== $month) {
227		$dt->setDate($year, $month, 1);
228		$dt->setTime(0, 0);
229		} elseif ($pday !== $day) {
230		$dt->setTime(0, 0);
231		} elseif ($phour !== $hour) {
232		$dt->setTime($hour, 0);
233		}
234
235		list($pday, $pmonth, $pyear, $phour) = [$day, $month, $year, $hour];
236
237		if (isset($this->register[3][$month]) === false) {
238		$dt->modify('+1 month');
239		continue;
240		} elseif (false === (isset($this->register[2][$day]) && isset($this->register[4][$weekday]))) {
241		$dt->modify('+1 day');
242		continue;
243		} elseif (isset($this->register[1][$hour]) === false) {
244		$dt->modify('+1 hour');
245		continue;
246		} elseif (isset($this->register[0][$minute]) === false) {
247		$dt->modify('+1 minute');
248		continue;
249		}
250
251		$result = $dt->getTimestamp();
252		}
253		}
254
255		return $result;
256		}
257
258		/**
259		* Parse whole cron expression
260		*
261		* @return array
262		* @throws \Exception
263		*/
264		private function parse()
265		{
266		$register = [];
267
268		if (sizeof($segments = preg_split('/\s+/', $this->expression)) === 5) {
269		foreach ($segments as $index => $segment) {
270		$this->parseSegment($index, $register, $segment);
271		}
272
273		$register[4][0] = isset($register[4][7]);
274		} else {
275		throw new \Exception('invalid number of segments');
276		}
277
278		return $register;
279		}
280
281		/**
282		* Parse one segment of a cron expression
283		*
284		* @param int $index
285		* @param string $segment
286		* @param array $register
287		* @throws \Exception
288		*/
289		private function parseSegment($index, array &$register, $segment)
290		{
291		$strv = [false, false, false, self::$months, self::$weekdays];
292
293		// month names, weekdays
294		if ($strv[$index] !== false && isset($strv[$index][strtolower($segment)])) {
295		// cannot be used with lists or ranges, see crontab(5) man page
296		$register[$index][$strv[$index][strtolower($segment)]] = true;
297		} else {
298		// split up current segment into single elements, e.g. "1,5-7,/2" => [ "1", "5-7", "/2" ]
299		foreach (explode(',', $segment) as $element) {
300		$this->parseElement($index, $register, $element);
301		}
302		}
303		}
304
305		/**
306		* @param int $index
307		* @param string $element
308		* @param array $register
309		* @throws \Exception
310		*/
311		private function parseElement($index, array &$register, $element)
312		{
313		if (false === strpos($element, '/')) {
314		$stepping = 1;
315		} else {
316		$stepping = $this->parseStepping($index, $element);
317		}
318
319		if (is_numeric($element)) {
320		$this->validateValue($index, $element);
321
322		if ($stepping !== 1) {
323		throw new \Exception('invalid combination of value and stepping notation');
324		}
325
326		$register[$index][intval($element)] = true;
327		} else {
328		$this->parseRange($index, $register, $element, $stepping);
329		}
330		}
331
332		/**
333		* Parse range of values, e.g. "5-10"
334		*
335		* @param int $index
336		* @param array $register
337		* @param string $range
338		* @param int $stepping
339		* @throws \Exception
340		*/
341		private function parseRange($index, array &$register, $range, $stepping)
342		{
343		if ($range === '*') {
344		$range = [self::$boundaries[$index]['min'], self::$boundaries[$index]['max']];
345		} elseif (strpos($range, '-') !== false) {
346		$range = $this->validateRange($index, explode('-', $range));
347		} else {
348		throw new \Exception('failed to parse list segment');
349		}
350
351		$this->parseValues($index, $register, $range, $stepping);
352		}
353
354		/**
355		* @param int $index
356		* @param array $register
357		* @param array $range
358		* @param int $stepping
359		*/
360		private function parseValues($index, array &$register, array $range, $stepping)
361		{
362		for ($i = self::$boundaries[$index]['min']; $i <= self::$boundaries[$index]['max']; $i++) {
363		if (($i - $range[0]) % $stepping === 0) {
364		if ($range[0] < $range[1]) {
365	View Code Duplication	if ($i >= $range[0] && $i <= $range[1]) {
		0 ignored issues – show Duplication introduced 2016-06-11 10:57 UTC by Report Bug Copy Issue Report This code seems to be duplicated across your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
366		$register[$index][$i] = true;
367		}
368	View Code Duplication	} elseif ($i >= $range[0] \|\| $i <= $range[1]) {
		0 ignored issues – show Duplication introduced 2016-06-11 10:57 UTC by Report Bug Copy Issue Report This code seems to be duplicated across your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
369		$register[$index][$i] = true;
370		}
371		}
372		}
373		}
374
375		/**
376		* Parse stepping notation, e.g. "/2"
377		*
378		* @param int $index
379		* @param string $element
380		* @return int
381		* @throws \Exception
382		*/
383		private function parseStepping($index, &$element)
384		{
385		if (sizeof($segments = explode('/', $element)) === 2) {
386		$element = $segments[0];
387
388		if (is_numeric($segments[1])) {
389		if ($segments[1] > 0 && $segments[1] <= self::$boundaries[$index]['max']) {
390		$stepping = $segments[1];
391		} else {
392		throw new \Exception('stepping value out of allowed range');
393		}
394		} else {
395		throw new \Exception('non-numeric stepping notation');
396		}
397		} else {
398		throw new \Exception('invalid stepping notation');
399		}
400
401		return $stepping;
402		}
403
404		/**
405		* Validate whether a given range of values exceeds allowed value boundaries
406		*
407		* @param int $index
408		* @param array $range
409		* @return array
410		* @throws \Exception
411		*/
412		private function validateRange($index, array $range)
413		{
414		if (sizeof($range) !== 2) {
415		throw new \Exception('invalid range notation');
416		}
417
418		foreach ($range as $value) {
419		$this->validateValue($index, $value);
420		}
421
422		return $range;
423		}
424
425		/**
426		* @param int $index
427		* @param int $value
428		* @throws \Exception
429		*/
430		private function validateValue($index, $value)
431		{
432		if (is_numeric($value)) {
433		if (intval($value) < self::$boundaries[$index]['min'] \|\|
434		intval($value) > self::$boundaries[$index]['max']) {
435		throw new \Exception('value boundary exceeded');
436		}
437		} else {
438		throw new \Exception('non-integer value');
439		}
440		}
441		}
442

poliander / cron