Passed
Push — master ( eb9638...42e076 )
by Mihail
07:15
created

Session::getOnlineCount()   A

Complexity

Conditions 2
Paths 2

Size

Total Lines 17
Code Lines 8

Duplication

Lines 0
Ratio 0 %

Importance

Changes 1
Bugs 1 Features 0
Metric Value
c 1
b 1
f 0
dl 0
loc 17
rs 9.4285
cc 2
eloc 8
nc 2
nop 0
1
<?php
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namespace Apps\ActiveRecord;
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use Ffcms\Core\App;
0 ignored issues
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Bug introduced by
This use statement conflicts with another class in this namespace, Apps\ActiveRecord\App.

Let’s assume that you have a directory layout like this:

.
|-- OtherDir
|   |-- Bar.php
|   `-- Foo.php
`-- SomeDir
    `-- Foo.php

and let’s assume the following content of Bar.php:

// Bar.php
namespace OtherDir;

use SomeDir\Foo; // This now conflicts the class OtherDir\Foo

If both files OtherDir/Foo.php and SomeDir/Foo.php are loaded in the same runtime, you will see a PHP error such as the following:

PHP Fatal error:  Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.php

However, as OtherDir/Foo.php does not necessarily have to be loaded and the error is only triggered if it is loaded before OtherDir/Bar.php, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias:

// Bar.php
namespace OtherDir;

use SomeDir\Foo as SomeDirFoo; // There is no conflict anymore.
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6
use Ffcms\Core\Arch\ActiveModel;
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/**
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 * Class Session. Session storage table.
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 * @package Apps\ActiveRecord
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 */
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class Session extends ActiveModel
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{
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    /**
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     * Get current active sessions count (authorized users online)
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     * @return int
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     */
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    public static function getOnlineCount()
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    {
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        if (App::$Memory->get('cache.users.online') !== null) {
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            return App::$Memory->get('cache.users.online');
0 ignored issues
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Bug Best Practice introduced by
The return type of return \Ffcms\Core\App::...('cache.users.online'); (object|array|string|boolean) is incompatible with the return type documented by Apps\ActiveRecord\Session::getOnlineCount of type integer.

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.

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22
        }
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        // get online sessions now
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        $time = time() - 600; // current_time - 10 minutes
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        $query = self::where('sess_time', '>=', $time);
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        $count = $query->count();
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        // save to memory
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        App::$Memory->set('cache.users.online', $count);
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        // return count
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        return $count;
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    }
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}