EventSourcedAggregateRoot::getEventHandlerName() - Code Metrics - Inspection of "Add more functionality to EventStream and refactor..." - DDDominio/event-sourcing - Measure and Improve Code Quality continuously with Scrutinizer

Completed

Push — master ( eb0ddf...6e23e2 )

by Daniel

created 2017-03-04 17:19 UTC

EventSourcedAggregateRoot::getEventHandlerName() A

↳ Parent: EventSourcedAggregateRoot

Complexity

Conditions	1
Paths	1

Size

Total Lines	4
Code Lines	2

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	2
CRAP Score	1

Importance

Changes	1
Bugs	0	Features	0

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

<?php

namespace DDDominio\EventSourcing\Common;

abstract class EventSourcedAggregateRoot implements EventSourcedAggregateRootInterface
{
    /**
     * @var EventStream
     */
    private $changes;

    /**
     * @var int
     */
    private $version = 0;

    /**
     * @param mixed $domainEvent
     * @throws DomainEventNotUnderstandableException
     */
    public function applyAndRecord($domainEvent)
    {
        $domainEvent = $this->ensureDomainEvent($domainEvent);
        $this->apply($domainEvent);
        $this->record($domainEvent);
    }

    /**
     * Record a Domain Event
     *
     * @param mixed $domainEvent
     */
    private function record($domainEvent)
    {
        $this->ensureChangesEventStream();
        $this->changes = $this->changes->append($domainEvent);
    }

    private function ensureChangesEventStream()
    {
        if (is_null($this->changes())) {
            $this->clearChanges();
        }
    }

    /**
     * Apply a Domain Event to the aggregate
     *
     * @param mixed $domainEvent
     */
    public function apply($domainEvent)
    {
        $domainEvent = $this->ensureDomainEvent($domainEvent);
        $eventHandlerName = $this->getEventHandlerName($domainEvent);
        if (method_exists($this, $eventHandlerName)) {
            $this->executeEventHandler($this, $eventHandlerName, $domainEvent);
        } else {
            $this->applyRecursively($eventHandlerName, $domainEvent);
        }
    }

    /**
     * @param $domainEvent
     * @return DomainEvent
     */
    private function ensureDomainEvent($domainEvent)
    {
        if (!$domainEvent instanceof DomainEvent) {
            $domainEvent = DomainEvent::produceNow($domainEvent);
        }
        return $domainEvent;
    }

    /**
     * @param string $eventHandlerName
     * @param mixed $domainEventData
     * @throws DomainEventNotUnderstandableException
     */
    private function applyRecursively($eventHandlerName, $domainEventData)
    {
        $applied = false;
        $reflectedClass = new \ReflectionClass(get_class($this));
        foreach ($reflectedClass->getProperties() as $property) {
            $propertyValue = $this->{$property->getName()};
            if (is_object($propertyValue)) {

                if (method_exists($propertyValue, $eventHandlerName)) {
                    $this->executeEventHandler($propertyValue, $eventHandlerName, $domainEventData);
                    $applied = true;
                }
            }
            if (is_array($propertyValue)) {

                foreach ($propertyValue as $item) {
                    if (method_exists($item, $eventHandlerName)) {
                        $this->executeEventHandler($item, $eventHandlerName, $domainEventData);
                        $applied = true;
                    }
                }
            }
        }
        if (!$applied) {
            throw DomainEventNotUnderstandableException::fromAggreagteAndEventTypes(
                get_class($this),
                get_class($domainEventData)
            );
        }
    }

    /**
     * @param DomainEvent $domainEvent
     * @return string
     */
    private function getEventHandlerName($domainEvent)
    {
        return $this->eventHandlerPrefix() . (new \ReflectionClass($domainEvent->data()))->getShortName();
    }

    /**
     * @return string
     */
    protected function eventHandlerPrefix()
    {
        return 'when';
    }

    /**
     * @param object $entity
     * @param string $eventHandlerName
     * @param DomainEvent $domainEvent
     */
    private function executeEventHandler($entity, $eventHandlerName, $domainEvent)
    {
        $entity->{$eventHandlerName}($domainEvent->data(), $domainEvent->occurredOn());
        $this->increaseAggregateVersion();
    }

    private function increaseAggregateVersion()
    {
        $this->version++;
    }

    /**
     * Recorded stream of Domain Events
     *
     * @return EventStream
     */
    public function changes()
    {
        return $this->changes;
class Author {
    private $name;

    public function __construct($name) {
        $this->name = $name;
    }

    public function getName() {
        return $this->name;
    }
}

abstract class Post {
    public function getAuthor() {
        return 'Johannes';
    }
}

class BlogPost extends Post {
    public function getAuthor() {
        return new Author('Johannes');
    }
}

class ForumPost extends Post { /* ... */ }

function my_function(Post $post) {
    echo strtoupper($post->getAuthor());
}
    }

    /**
     * Current version of the aggregate
     *
     * @return int
     */
    public function version()
    {
        return $this->version;
    }

    /**
     * The version of the aggregate before applying changes
     *
     * @return int
     */
    public function originalVersion()
    {
        return $this->version - count($this->changes());
    }

    /**
     * Removes recorded domain events
     */
    public function clearChanges()
    {
        $this->changes = EventStream::buildEmpty();
    }
}


1			<?php
2
3			namespace DDDominio\EventSourcing\Common;
4
5			abstract class EventSourcedAggregateRoot implements EventSourcedAggregateRootInterface
6			{
7			/**
8			* @var EventStream
9			*/
10			private $changes;
11
12			/**
13			* @var int
14			*/
15			private $version = 0;
16
17			/**
18			* @param mixed $domainEvent
19			* @throws DomainEventNotUnderstandableException
20			*/
21	15		public function applyAndRecord($domainEvent)
22			{
23	15		$domainEvent = $this->ensureDomainEvent($domainEvent);
24	15		$this->apply($domainEvent);
25	15		$this->record($domainEvent);
26	15		}
27
28			/**
29			* Record a Domain Event
30			*
31			* @param mixed $domainEvent
32			*/
33	15		private function record($domainEvent)
34			{
35	15		$this->ensureChangesEventStream();
36	15		$this->changes = $this->changes->append($domainEvent);
37	15		}
38
39	15		private function ensureChangesEventStream()
40			{
41	15		if (is_null($this->changes())) {
42	15		$this->clearChanges();
43			}
44	15		}
45
46			/**
47			* Apply a Domain Event to the aggregate
48			*
49			* @param mixed $domainEvent
50			*/
51	25		public function apply($domainEvent)
52			{
53	25		$domainEvent = $this->ensureDomainEvent($domainEvent);
54	25		$eventHandlerName = $this->getEventHandlerName($domainEvent);
55	25		if (method_exists($this, $eventHandlerName)) {
56	24		$this->executeEventHandler($this, $eventHandlerName, $domainEvent);
57			} else {
58	3		$this->applyRecursively($eventHandlerName, $domainEvent);
59			}
60	24		}
61
62			/**
63			* @param $domainEvent
64			* @return DomainEvent
65			*/
66	25		private function ensureDomainEvent($domainEvent)
67			{
68	25		if (!$domainEvent instanceof DomainEvent) {
69	25		$domainEvent = DomainEvent::produceNow($domainEvent);
70			}
71	25		return $domainEvent;
72			}
73
74			/**
75			* @param string $eventHandlerName
76			* @param mixed $domainEventData
77			* @throws DomainEventNotUnderstandableException
78			*/
79	3		private function applyRecursively($eventHandlerName, $domainEventData)
80			{
81	3		$applied = false;
82	3		$reflectedClass = new \ReflectionClass(get_class($this));
83	3		foreach ($reflectedClass->getProperties() as $property) {
84	3		$propertyValue = $this->{$property->getName()};
85	3	View Code Duplication	if (is_object($propertyValue)) {
			0 ignored issues – show Duplication introduced 2017-02-11 16:14 UTC by Report Bug Copy Issue Report This code seems to be duplicated across your project. Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation. You can also find more detailed suggestions in the “Code” section of your repository. Loading history...
86	1		if (method_exists($propertyValue, $eventHandlerName)) {
87	1		$this->executeEventHandler($propertyValue, $eventHandlerName, $domainEventData);
88	1		$applied = true;
89			}
90			}
91	3	View Code Duplication	if (is_array($propertyValue)) {
			0 ignored issues – show Duplication introduced 2017-02-11 16:14 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...
92	2		foreach ($propertyValue as $item) {
93	1		if (method_exists($item, $eventHandlerName)) {
94	1		$this->executeEventHandler($item, $eventHandlerName, $domainEventData);
95	3		$applied = true;
96			}
97			}
98			}
99			}
100	3		if (!$applied) {
101	1		throw DomainEventNotUnderstandableException::fromAggreagteAndEventTypes(
102			get_class($this),
103			get_class($domainEventData)
104			);
105			}
106	2		}
107
108			/**
109			* @param DomainEvent $domainEvent
110			* @return string
111			*/
112	25		private function getEventHandlerName($domainEvent)
113			{
114	25		return $this->eventHandlerPrefix() . (new \ReflectionClass($domainEvent->data()))->getShortName();
115			}
116
117			/**
118			* @return string
119			*/
120	25		protected function eventHandlerPrefix()
121			{
122	25		return 'when';
123			}
124
125			/**
126			* @param object $entity
127			* @param string $eventHandlerName
128			* @param DomainEvent $domainEvent
129			*/
130	24		private function executeEventHandler($entity, $eventHandlerName, $domainEvent)
131			{
132	24		$entity->{$eventHandlerName}($domainEvent->data(), $domainEvent->occurredOn());
133	24		$this->increaseAggregateVersion();
134	24		}
135
136	24		private function increaseAggregateVersion()
137			{
138	24		$this->version++;
139	24		}
140
141			/**
142			* Recorded stream of Domain Events
143			*
144			* @return EventStream
145			*/
146	18		public function changes()
147			{
148	18		return $this->changes;
			0 ignored issues – show Bug Best Practice introduced 2017-03-04 16:59 UTC by Report Bug Copy Issue Report The return type of `return $this->changes;` (`DDDominio\EventSourcing\Common\EventStream`) is incompatible with the return type declared by the interface `DDDominio\EventSourcing\...eRootInterface::changes` of type `DDDominio\EventSourcing\Common\DomainEvent[]`. If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design. Let’s take a look at an example: class Author { private $name; public function __construct($name) { $this->name = $name; } public function getName() { return $this->name; } } abstract class Post { public function getAuthor() { return 'Johannes'; } } class BlogPost extends Post { public function getAuthor() { return new Author('Johannes'); } } class ForumPost extends Post { /* ... */ } function my_function(Post $post) { echo strtoupper($post->getAuthor()); } Our function `my_function` expects a `Post` object, and outputs the author of the post. The base class `Post` returns a simple string and outputting a simple string will work just fine. However, the child class `BlogPost` which is a sub-type of `Post` instead decided to return an `object`, and is therefore violating the SOLID principles. If a `BlogPost` were passed to `my_function`, PHP would not complain, but ultimately fail when executing the `strtoupper` call in its body. Loading history...
149			}
150
151			/**
152			* Current version of the aggregate
153			*
154			* @return int
155			*/
156	8		public function version()
157			{
158	8		return $this->version;
159			}
160
161			/**
162			* The version of the aggregate before applying changes
163			*
164			* @return int
165			*/
166	5		public function originalVersion()
167			{
168	5		return $this->version - count($this->changes());
169			}
170
171			/**
172			* Removes recorded domain events
173			*/
174	19		public function clearChanges()
175			{
176	19		$this->changes = EventStream::buildEmpty();
177	19		}
178			}
179

DDDominio / event-sourcing

Push — master ( eb0ddf...6e23e2 )

EventSourcedAggregateRoot::getEventHandlerName() A

Complexity

Size

Duplication

Code Coverage

Importance

Duplication Side-by-Side

Filter issues like