CachingDecorator::createCacheKey() - Code Metrics - Inspection of "Allow overriding cache expiry and cache key for ca..." - adamnicholson/Chief - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( ee9284...94e6de )

by Adam

created 2016-03-16 14:12 UTC

CachingDecorator::createCacheKey() A

↳ Parent: CachingDecorator

Complexity

Conditions	1
Paths	1

Size

Total Lines	4
Code Lines	2

Duplication

Lines	0
Ratio	0 %

Importance

Changes	1
Bugs	0	Features	1

Metric	Value
c	1
b	0
f	1
dl	0
loc	4
rs	10
cc	1
eloc	2
nc	1
nop	1

<?php

namespace Chief\Decorators;

use Chief\Busses\SynchronousCommandBus;
use Chief\CacheableCommand;
use Chief\Command;
use Chief\CommandBus;
use Chief\Decorator;
use Chief\HasCacheOptions;
use Psr\Cache\CacheItemInterface;
use Psr\Cache\CacheItemPoolInterface;

class CachingDecorator implements Decorator
{
    /**
     * @var CommandBus
     */
    private $innerBus;
    /**
     * @var CacheItemPoolInterface
     */
    private $cache;
    /**
     * @var int
     */
    private $expiresAfter;

    /**
     * CachingDecorator constructor.
     * @param CacheItemPoolInterface $cache
     * @param int $expiresAfter
     * @param CommandBus $innerCommandBus
     */
    public function __construct(CacheItemPoolInterface $cache, $expiresAfter = 3600, CommandBus $innerCommandBus = null)
    {
        $this->cache = $cache;
        $this->expiresAfter = $expiresAfter;
        $this->setInnerBus($innerCommandBus ?: new SynchronousCommandBus);
    }

    /**
     * @inheritdoc
     */
    public function setInnerBus(CommandBus $bus)
    {
        $this->innerBus = $bus;
    }

    /**
     * @inheritdoc
     */
    public function execute(Command $command)
    {
        if (!$command instanceof CacheableCommand) {
            return $this->innerBus->execute($command);
        }

        $cached = $this->cache->getItem($this->getCacheKey($command));
        if ($cached->isHit()) {
            return $cached->get();
        }

        $value = $this->innerBus->execute($command);

        $this->cache->save($this->createCacheItem($command, $value));

        return $value;
    }

    /**
     * Create a new cache item to be persisted.
     *
     * @param CacheableCommand $command
     * @param mixed $value
     * @return CacheItemInterface
     */
    private function createCacheItem(CacheableCommand $command, $value)
    {
        return $this->cache->getItem($this->getCacheKey($command))
            ->expiresAfter($this->getCacheExpiry($command))
            ->set($value);
    }

    /**
     * Create the key to be used when saving this item to the cache pool.
     *
     * The cache item key is taken as a the (string) serialized command, to ensure the return value is unique
     * depending on the command properties; that serialized string is then md5'd to ensure it doesn't
     * overflow any string length limits the implementing CacheItemPoolInterface library has.
     *
     * @param CacheableCommand $command
     * @return string
     */
    private function getCacheKey(CacheableCommand $command)
    {
        if ($command instanceof HasCacheOptions && $command->getCacheKey()) {
''   == false // true
''   == null  // true
'ab' == false // false
'ab' == null  // false

// It is often better to use strict comparison
'' === false // false
'' === null  // false
            return $command->getCacheKey();
        }

        return md5(serialize($command));
    }

    /**
     * Determine when this CachableCommand should expire, in terms of seconds from now.
     *
     * @param CacheableCommand $command
     * @return int
     */
    private function getCacheExpiry(CacheableCommand $command)
    {
        if ($command instanceof HasCacheOptions && $command->getCacheExpiry() > 0) {
            return $command->getCacheExpiry();
        }

        return $this->expiresAfter;
    }
}


1			<?php
2
3			namespace Chief\Decorators;
4
5			use Chief\Busses\SynchronousCommandBus;
6			use Chief\CacheableCommand;
7			use Chief\Command;
8			use Chief\CommandBus;
9			use Chief\Decorator;
10			use Chief\HasCacheOptions;
11			use Psr\Cache\CacheItemInterface;
12			use Psr\Cache\CacheItemPoolInterface;
13
14			class CachingDecorator implements Decorator
15			{
16			/**
17			* @var CommandBus
18			*/
19			private $innerBus;
20			/**
21			* @var CacheItemPoolInterface
22			*/
23			private $cache;
24			/**
25			* @var int
26			*/
27			private $expiresAfter;
28
29			/**
30			* CachingDecorator constructor.
31			* @param CacheItemPoolInterface $cache
32			* @param int $expiresAfter
33			* @param CommandBus $innerCommandBus
34			*/
35			public function __construct(CacheItemPoolInterface $cache, $expiresAfter = 3600, CommandBus $innerCommandBus = null)
36			{
37			$this->cache = $cache;
38			$this->expiresAfter = $expiresAfter;
39			$this->setInnerBus($innerCommandBus ?: new SynchronousCommandBus);
40			}
41
42			/**
43			* @inheritdoc
44			*/
45			public function setInnerBus(CommandBus $bus)
46			{
47			$this->innerBus = $bus;
48			}
49
50			/**
51			* @inheritdoc
52			*/
53			public function execute(Command $command)
54			{
55			if (!$command instanceof CacheableCommand) {
56			return $this->innerBus->execute($command);
57			}
58
59			$cached = $this->cache->getItem($this->getCacheKey($command));
60			if ($cached->isHit()) {
61			return $cached->get();
62			}
63
64			$value = $this->innerBus->execute($command);
65
66			$this->cache->save($this->createCacheItem($command, $value));
67
68			return $value;
69			}
70
71			/**
72			* Create a new cache item to be persisted.
73			*
74			* @param CacheableCommand $command
75			* @param mixed $value
76			* @return CacheItemInterface
77			*/
78			private function createCacheItem(CacheableCommand $command, $value)
79			{
80			return $this->cache->getItem($this->getCacheKey($command))
81			->expiresAfter($this->getCacheExpiry($command))
82			->set($value);
83			}
84
85			/**
86			* Create the key to be used when saving this item to the cache pool.
87			*
88			* The cache item key is taken as a the (string) serialized command, to ensure the return value is unique
89			* depending on the command properties; that serialized string is then md5'd to ensure it doesn't
90			* overflow any string length limits the implementing CacheItemPoolInterface library has.
91			*
92			* @param CacheableCommand $command
93			* @return string
94			*/
95			private function getCacheKey(CacheableCommand $command)
96			{
97			if ($command instanceof HasCacheOptions && $command->getCacheKey()) {
			0 ignored issues – show Bug Best Practice introduced 2016-03-16 14:15 UTC by Report Bug Copy Issue Report The expression `$command->getCacheKey()` of type `string\|null` is loosely compared to `true`; this is ambiguous if the string can be empty. You might want to explicitly use `!== null` instead. In PHP, under loose comparison (like `==`, or `!=`, or `switch` conditions), values of different types might be equal. For `string` values, the empty string `''` is a special case, in particular the following results might be unexpected: '' == false // true '' == null // true 'ab' == false // false 'ab' == null // false // It is often better to use strict comparison '' === false // false '' === null // false Loading history...
98			return $command->getCacheKey();
99			}
100
101			return md5(serialize($command));
102			}
103
104			/**
105			* Determine when this CachableCommand should expire, in terms of seconds from now.
106			*
107			* @param CacheableCommand $command
108			* @return int
109			*/
110			private function getCacheExpiry(CacheableCommand $command)
111			{
112			if ($command instanceof HasCacheOptions && $command->getCacheExpiry() > 0) {
113			return $command->getCacheExpiry();
114			}
115
116			return $this->expiresAfter;
117			}
118			}
119

adamnicholson / Chief

GitHub Access Token became invalid

Push — master ( ee9284...94e6de )

CachingDecorator::createCacheKey() A

Complexity

Size

Duplication

Importance

Duplication Side-by-Side

Filter issues like