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

Completed

Push — master ( 9aa418...979aa5 )

by René

created 2016-06-11 14:32 UTC

Cron C

↳ Parent: Project

Complexity

Total Complexity

Size/Duplication

Total Lines	416
Duplicated Lines	3.37 %

Coupling/Cohesion

Components	1
Dependencies	0

Importance

Changes	12
Bugs	0	Features	0

Metric	Value
wmc	61
c	12
b	0
f	0
lcom	1
cbo	0
dl	14
loc	416
rs	6.018

12 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
C	parseElement()	4	28	7
B	parseRange()	6	21	9
B	validateRange()	4	17	6
B	parseStepping()	0	25	6

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;
    }

    /**
     * @param int $index
     * @param string $segment
     * @param array $register
     * @throws \Exception
     */
    private function parseSegment($index, &$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)
    {
        $stepping = $this->parseStepping($index, $element);

        // single value
        if (is_numeric($element)) {
            if (intval($element) < self::$boundaries[$index]['min'] ||

                intval($element) > self::$boundaries[$index]['max']) {
                throw new \Exception('value out of allowed range');
            }

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

            $register[$index][intval($element)] = true;
        } else {
            if ($element === '*') {
                $range = [self::$boundaries[$index]['min'], self::$boundaries[$index]['max']];
            } elseif (strpos($element, '-') !== false) {
                $range = explode('-', $element);
            } else {
                throw new \Exception('failed to parse list segment');
            }

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

    /**
     * @param int $index
     * @param array $register
     * @param array $range
     * @param int $stepping
     * @throws \Exception
     */
    private function parseRange($index, array &$register, array $range, $stepping)
    {
        $this->validateRange($index, $range);

        // fill matching register
        if ($range[0] === $range[1]) {
            $register[$index][$range[0]] = true;
        } else {
            for ($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;
                    }
                }
            }
        }
    }

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

        foreach ($range as $value) {
            if (is_numeric($value)) {
                if (intval($value) < self::$boundaries[$index]['min'] ||

                    intval($value) > self::$boundaries[$index]['max']) {
                    throw new \Exception('invalid range start or end value');
                }
            } else {
                throw new \Exception('non-numeric range notation');
            }
        }
    }

    /**
     * @param int $index
     * @param string $element
     * @return int
     * @throws \Exception
     */
    private function parseStepping($index, &$element)
    {
        $stepping = 1;

        // parse stepping notation
        if (strpos($element, '/') !== false) {
            if (sizeof($stepsegments = explode('/', $element)) === 2) {
                $element = $stepsegments[0];

                if (is_numeric($stepsegments[1])) {
                    if ($stepsegments[1] > 0 && $stepsegments[1] <= self::$boundaries[$index]['max']) {
                        $stepping = intval($stepsegments[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;
    }
}


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		* @param int $index
283		* @param string $segment
284		* @param array $register
285		* @throws \Exception
286		*/
287		private function parseSegment($index, &$register, $segment)
288		{
289		$strv = [false, false, false, self::$months, self::$weekdays];
290
291		// month names, weekdays
292		if ($strv[$index] !== false && isset($strv[$index][strtolower($segment)])) {
293		// cannot be used with lists or ranges, see crontab(5) man page
294		$register[$index][$strv[$index][strtolower($segment)]] = true;
295		} else {
296		// split up current segment into single elements, e.g. "1,5-7,/2" => [ "1", "5-7", "/2" ]
297		foreach (explode(',', $segment) as $element) {
298		$this->parseElement($index, $register, $element);
299		}
300		}
301		}
302
303		/**
304		* @param int $index
305		* @param string $element
306		* @param array $register
307		* @throws \Exception
308		*/
309		private function parseElement($index, array &$register, $element)
310		{
311		$stepping = $this->parseStepping($index, $element);
312
313		// single value
314		if (is_numeric($element)) {
315	View Code Duplication	if (intval($element) < self::$boundaries[$index]['min'] \|\|
		0 ignored issues – show Duplication introduced 2016-06-11 14:16 UTC by Report Bug Copy Issue Report This code seems to be duplicated across your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
316		intval($element) > self::$boundaries[$index]['max']) {
317		throw new \Exception('value out of allowed range');
318		}
319
320		if ($stepping !== 1) {
321		throw new \Exception('invalid combination of value and stepping notation');
322		}
323
324		$register[$index][intval($element)] = true;
325		} else {
326		if ($element === '*') {
327		$range = [self::$boundaries[$index]['min'], self::$boundaries[$index]['max']];
328		} elseif (strpos($element, '-') !== false) {
329		$range = explode('-', $element);
330		} else {
331		throw new \Exception('failed to parse list segment');
332		}
333
334		$this->parseRange($index, $register, $range, $stepping);
335		}
336		}
337
338		/**
339		* @param int $index
340		* @param array $register
341		* @param array $range
342		* @param int $stepping
343		* @throws \Exception
344		*/
345		private function parseRange($index, array &$register, array $range, $stepping)
346		{
347		$this->validateRange($index, $range);
348
349		// fill matching register
350		if ($range[0] === $range[1]) {
351		$register[$index][$range[0]] = true;
352		} else {
353		for ($i = self::$boundaries[$index]['min']; $i <= self::$boundaries[$index]['max']; $i++) {
354		if (($i - $range[0]) % $stepping === 0) {
355		if ($range[0] < $range[1]) {
356	View Code Duplication	if ($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...
357		$register[$index][$i] = true;
358		}
359	View Code Duplication	} elseif ($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...
360		$register[$index][$i] = true;
361		}
362		}
363		}
364		}
365		}
366
367		/**
368		* Validate range of values
369		*
370		* @param int $index
371		* @param array $range
372		* @throws \Exception
373		*/
374		private function validateRange($index, array $range)
375		{
376		if (sizeof($range) !== 2) {
377		throw new \Exception('invalid range notation');
378		}
379
380		foreach ($range as $value) {
381		if (is_numeric($value)) {
382	View Code Duplication	if (intval($value) < self::$boundaries[$index]['min'] \|\|
		0 ignored issues – show Duplication introduced 2016-06-11 14:16 UTC by Report Bug Copy Issue Report This code seems to be duplicated across your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
383		intval($value) > self::$boundaries[$index]['max']) {
384		throw new \Exception('invalid range start or end value');
385		}
386		} else {
387		throw new \Exception('non-numeric range notation');
388		}
389		}
390		}
391
392		/**
393		* @param int $index
394		* @param string $element
395		* @return int
396		* @throws \Exception
397		*/
398		private function parseStepping($index, &$element)
399		{
400		$stepping = 1;
401
402		// parse stepping notation
403		if (strpos($element, '/') !== false) {
404		if (sizeof($stepsegments = explode('/', $element)) === 2) {
405		$element = $stepsegments[0];
406
407		if (is_numeric($stepsegments[1])) {
408		if ($stepsegments[1] > 0 && $stepsegments[1] <= self::$boundaries[$index]['max']) {
409		$stepping = intval($stepsegments[1]);
410		} else {
411		throw new \Exception('stepping value out of allowed range');
412		}
413		} else {
414		throw new \Exception('non-numeric stepping notation');
415		}
416		} else {
417		throw new \Exception('invalid stepping notation');
418		}
419		}
420
421		return $stepping;
422		}
423		}
424

poliander / cron