I have the following code and I don't know how to use the interface, I feel like I don't need it but I want to
I am using only composer for autoloading without any framework
service code (run from batch file from the example)
try {
$test = new testClass(); //how do I put here the interface , i dont want to put it here
$test->run();
}
catch(\Exception $e) {
echo $e->getMessage() . "\n";
die;
}
Test Class:
class TestClass extends AbstractClass
{
private $_repo;
public function __construct(RepositoryInterface $repo)
{
parent::__construct();
$this->_repo = $repo;
}
public function run(){
}
AbstractClass
abstract class AbstractClass
{
protected $logger;
protected $db;
public function __construct()
{
Configuration::config();
$this->db = PDOConnection::dbConnect();
}
it is not working, now I just call to the testRepository that implement the interface directly, without calling to the interface
so how can I register the interface to the constructor or I have to call it each place I initiate a testclass object
thanks
In your TestClass method construct need one argument.
public function __construct(RepositoryInterface $repo)
When you create object of class you did not use any arguments:
$test = new testClass();
Then add argument in new testClass($repo); or change __construct method like
public function __construct(RepositoryInterface $repo = null)
I think you're missing some understanding. #J.Litvak's answer does not provide this info either.
class TestClass extends AbstractClass
{
private $_repo;
public function __construct(RepositoryInterface $repo)
{
parent::__construct();
$this->_repo = $repo;
}
}
This class has a constructor which requires an object which implements the RepositoryInterface.
As such, the variable you pass must be an object, and it must have used that Interface. With me so far?
This means that the following code is incorrect.
try {
$test = new testClass();
$test->run();
} catch(\Exception $e) { ... }
The line initializing the $test variable with an instance of TestClass, must an object which uses the RepositoryInterface for the TestClass::__construct function.
So, somewhere, you must create or have:
class CustomRepository implements RepositoryInterface
{
public function findAll() { ... }
}
Now, update your try{} / catch () {} to the following:
$customRepository = new CustomerRepository();
try {
$test = new testClass($customRepository);
$test->run();
} catch(\Exception $e) { ... }
Which should work, as the CustomRepository class implements the interface you require in the TestClass::__construct parameters.
Have a look at some of the PHP docs:
interfaces
constructors and destructors
I figured it out with PHP DI module and inject it via composer
something like :
return [
// Bind an interface to an implementation
RepositoryInterface::class => object(Repository::class),
];
Related
Have a look at the following trait:
trait PrimaryModelRest {
use RestController;
protected $primaryModel;
public function __construct() {
$mc = $this->getPrimaryModelClass();
try {
$this->primaryModel = new $mc();
if(!($this->primaryModel instanceof Model)) {
throw new ClassNotFoundException("Primary Model fatal exception: The given Class is not an instance of Illuminate\Database\Eloquent\Model");
}
} catch (Exception $e) {
throw new WrongImplementationException("Primary Model Exception: Class not found.");
}
}
/**
* #return string: Classname of the primary model.
*/
public abstract function getPrimaryModelClass();
// various functions here
}
As you can see the trait makes sure that the using class holds a certain model instance and it implements certain methods. This works as long as the implementing class does not override the constructor.
So here is my question: I want to make sure that either the constructor is called or a better solution, such that I can instantiate this model on initialization.
Please make in answer which respects Multiple inheritance as well es Multi-Level inheritance.
I think you are trying to make the trait do a job it is not designed for.
Traits are not a form of multiple inheritance, but rather "horizontal reuse" - they're often described as "compiler-assisted copy-and-paste". As such, the job of a trait is to provide some code, so that you don't have to copy it into the class manually. The only relationship it has is with the class where the use statement occurs, where the code is "pasted". To aid in this role, it can make some basic requirements of that target class, but after that, the trait takes no part in inheritance.
In your example, you are concerned that a sub-class might try to access $primaryModel without running the constructor code which initialises it, and you are trying to use the trait to enforce that; but this is not actually the trait's responsibility.
The following definitions of class Sub are completely equivalent:
trait Test {
public function foo() {
echo 'Hello, World!';
}
}
class ParentWithTrait {
use Test;
}
class Sub inherits ParentWithTrait {
}
vs:
class ParentWithMethodDefinition {
public function foo() {
echo 'Hello, World!';
}
}
class Sub inherits ParentWithMethodDefinition {
}
In either case, class Sub could have its own definition of foo(), and by-pass the logic you'd written in the parent class.
The only contract that can prevent that is the final keyword, which in your case would mean marking your constructor as final. You can then provide an extension point that can be overridden for sub-classes to add their own initialisation:
class Base {
final public function __construct() {
important_things(); // Always run this!
$this->onConstruct(); // Extension point
}
protected function onConstruct() {
// empty default definition
}
}
class Sub {
protected function onConstruct() {
stuff_for_sub(); // Runs after mandatory important_things()
}
}
A trait can also mark its constructor as final, but this is part of the code being pasted, not a requirement on the class using the trait. You could actually use a trait with a constructor, but then write a new constructor as well, and it would mask the trait's version completely:
trait Test {
final public function __construct() {
echo "Trait Constructor";
}
}
class Noisy {
use Test;
}
class Silent {
use Test;
public function __construct() {
// Nothing
}
}
As far as the trait is concerned, this is like buying a bottle of beer and pouring it down the sink: you asked for its code and didn't use it, but that's your problem.
Crucially, though, you can also alias the methods of the trait, creating a new method with the same code but a different name and/or a different visibility. This means you can mix in code from traits which declare constructors, and use that code in a more complex constructor, or somewhere else in the class altogether.
The target class might also use the "final + hook" pattern:
trait TestOne {
final public function __construct() {
echo "Trait TestOne Constructor\n";
}
}
trait TestTwo {
final public function __construct() {
echo "Trait TestTwo Constructor\n";
}
}
class Mixed {
final public function __construct() {
echo "Beginning\n";
$this->testOneConstructor();
echo "Middle\n";
$this->testTwoConstructor();
echo "After Traits\n";
$this->onConstruct();
echo "After Sub-Class Hook\n";
}
use TestOne { __construct as private testOneConstructor; }
use TestTwo { __construct as private testTwoConstructor; }
protected function onConstruct() {
echo "Default hook\n";
}
}
class ChildOfMixed extends Mixed {
protected function onConstruct() {
echo "Child hook\n";
}
}
The trait hasn't forced the Mixed class to implement this pattern, but it has enabled it, in keeping with its purpose of facilitating code reuse.
Interestingly, the below code doesn't work, because the as keyword adds an alias, rather than renaming the normal method, so this ends up trying to override the final constructor from Mixed:
class ChildOfMixed extends Mixed {
use TestTwo { __construct as private testTwoConstructor; }
protected function onConstruct() {
$this->testTwoConstructor();
echo "Child hook\n";
}
}
Use a base class, this will let you handle the trait as a parent.
<?php
trait StorageTrait
{
public function __construct()
{
echo "Storage Trait";
}
}
class StorageAttempt
{
use StorageTrait;
public function __construct()
{
parent::__construct();
echo " - Storage Attempt";
}
}
abstract class StorageBase
{
use StorageTrait;
}
class MyStorage extends StorageBase
{
public function __construct()
{
parent::__construct();
echo ' - My Storage';
}
}
new StorageAttempt(); // won't work - will trigger error
new MyStorage(); // will display "Storage Trait - My Storage"
Also if you are using traits you can also work with properties and getters & setters.
Example: A Storage trait involves that a Storage Engine will be used. You can add the storageEngine property and its getters and setters. (with or without Type Hinting)
interface StorageEngineInterface{}
trait StorageTrait
{
/**
* #var StorageEngineInterface
*/
protected $storageEngine;
/**
* #return StorageEngineInterface
*/
public function getStorageEngine(): StorageEngineInterface
{
return $this->storageEngine;
}
/**
* #param StorageEngineInterface $storageEngine
*/
public function setStorageEngine(StorageEngineInterface $storageEngine)
{
$this->storageEngine = $storageEngine;
return $this;
}
}
Note: this is just an explanation so you can better understand how Traits work
UPDATE
To avoid conflict you can use aliases for trait methods. This way you can use both constructors (from trait and from extended class) you can do the following
class DifferentStorage
{
public function __construct()
{
echo ' diff ';
}
}
class MyDifferentStorage extends DifferentStorage
{
use StorageTrait {
StorageTrait::__construct as otherConstructor;
}
public function __construct()
{
parent::__construct();
self::otherConstructor();
}
}
You could use the interface injection pattern: implement an interface iPrimaryModelRest into the same class that uses the trait PrimaryModelRest:
interface iPrimaryModelRest {
public function init();
public abstract function getPrimaryModelClass();
}
The class that uses the trait woud look like this:
class cMyClass implements iPrimaryModelRest {
use PrimaryModelRest;
}
Then, whenever the class is instantiated (not only autoloaded) you could call a special factory-like initialisation function like this:
class cMyApp {
public function start() {
/** #var cMyClass $oClass */ // enlighten IDE
$oClass = $this->init(new cMyClass);
}
public function init($oClass) {
if ($oClass instanceof iPrimaryModelRest) {$oClass->init();}
if ($oClass instanceof whateverinterface) {
// pass optional stuff, like database connection
}
}
}
The interface is used to determine the capabilities of the class, and sets data/runs corresponding functions. If I'm not mistaken then this pattern is called a Service Locator.
I needed a trait for database connection. To avoid using the __construct in a trait, I've used a magic getter instead:
trait WithDatabaseConnection
{
public function __get(string $name)
{
if ($name === 'pdo') {
return App::make(\PDO::class);
}
trigger_error("Property $name does not exist.");
return null;
}
}
class Foo {
use WithDatabaseConnection;
public function save() {
$this->pdo->query('...');
}
}
I have a Factory Method to instance a class. Is there a way to prevent this class from direct instancing?
The only option I see is to use an argument passed into the __construct(), but that's not something I'm looking for.
On the other hand, making the __construct() private would be ideal, but I don't want MyClass to extend the Factory without actual need.
What do you guys think?
Factory Method:
class Factory
{
public static function instance()
{
return new MyClass(true);
}
}
MyClass:
class MyClass
{
public function __construct($isFactory = false)
{
if (!$isFactory) {
throw new Exception('Use Factory::instance() to create an object');
}
}
}
There are hacks to do that:
abusing inheritance to use a protected constructor
putting the factory method inside the class so that it can call the private constructor, which is actually not a hack. But then why not using the constructor in the first place?
using reflection to access the private constructor
I'm not promoting anything of that. What I personally do is documenting the API with things like #internal and leave it to the client following that contract.
In essence, your code should have read something like this:
THE FACTORY
<?php
class Factory {
public static function instance(){
return new MyClass(true); //HERE YOU ARE INSTANTIATING
}
}
THE CLASS TO BE INSTANTIATED VIA THE FACTORY
<?php
//NOT MyClass() <--- YOU ARE DEFINING.... NOT INSTANTIATING...
class MyClass {
public function __construct($isFactory = false) {
if (!$isFactory) {
throw new Exception('Use Factory::instance() to create an object');
}
}
//...MORE METHODS
}
Could you try this instead?
<?php
class Factory
{
private static $FACTORY_GUARANTOR; //ONLY SET DURING INSTANTIATION
public static function instance($type) {
if (class_exists($type)) {
self::$FACTORY_GUARANTOR = 1;
$instance = new $type();
self::$FACTORY_GUARANTOR = null;
return $instance;
}
else {
throw new Exception("Class not found...");
}
}
//YOU CAN GET $FACTORYGUARANTOR EXTERNALLY BUT NEVER SET IT;
public static function getGuarantor(){
return self::$FACTORY_GUARANTOR;
}
}
class MyClass {
protected $property1;
protected $property3;
protected $property2;
public function __construct() {
// IF SOMEONE TRIES TO INSTANTIATE THE CLASS OUTSIDE OF THE FACTORY... BLOW A WHISTLE
if(!Factory::getGuarantor()){
throw new Exception('Use Factory::instance() to create an object');
}
// IF THE PROGRAM MADE IT TO THIS POINT;
// JUST INSTANTIATE THE CLASS BECAUSE MOST LIKELY IT IS COMING FROM THE FACTORY
var_dump($this); // A LITTLE CONFIRMATION....
}
//...MORE METHODS
}
// TRY IT OUT:
/*INSTANCE A: RIGHT*/ $theClass = Factory::instance("MyClass"); //INSTANTIATES THE CLASS
/*INSTANCE B: WRONG*/ $theClass = new MyClass(); //THROWS AN EXCEPTION
The easiest way is to define your base class as abstract. The abstract classes cannot be directly instanced, so you will have to redefine their abstract members in the inherited classes:
abstract class Factory
{
abstract public function foo();
}
class InheritedClass extends Factory
{
public function foo()
{
// Do something
}
}
// $obj1 = new Factory(); // Will produce an error
$obj1 = new InheritedClass(); // Will be executed successfully
You can read more for the abstract classes here: PHP: Class Abstraction - Manual.
For me, the best way is to use ReflectionClass:
class MyClass
{
public const FRIEND_CLASSES = [Factory::class];
protected function __construct() {}
}
trait Constructor
{
protected function createObject(string $className, array $args = [])
{
if (!in_array(static::class, $className::FRIEND_CLASSES)) {
throw new \Exception("Call to private or protected {$className}::__construct() from invalid context");
}
$reflection = new ReflectionClass($className);
$constructor = $reflection->getConstructor();
$constructor->setAccessible(true);
$object = $reflection->newInstanceWithoutConstructor();
$constructor->invokeArgs($object, $args);
return $object;
}
}
class Factory
{
use Constructor;
public function MyClass(): MyClass
{
return $this->createObject(MyClass::class);
}
}
In constant FRIEND_CLASSES you can define in which classes the class can be instanced.
trait is used because this functionality can be used in different factories that are not related.
If you need to put parameters into constructor of the class, put them as second parameter of createObject.
Details I described in the article "Forbidding of creating objects outside factory in PHP"
Game.php
<?php
class Game
{
public $db;
public function __construct()
{
$this->db = new DB;
}
public function result()
{
return $this->db->data();
}
}
DB.php
<?php
class DB
{
public function data()
{
return false;
}
}
GameTest.php
<?php
use Mockery as m;
class GameTest extends PHPUnit_Framework_TestCase
{
public function testResult()
{
$game = m::mock(new Game);
$game->shouldReceive('data')
->once()
->andReturn(true);
$expected = $game->result();
$this->assertTrue($expected);
}
public function tearDown()
{
m::close();
}
}
This is my solution but totally not work, I guess if I want to get setting from __construct I need to mock a new class, I got message Failed asserting that false is true. which mean the mock thing is not work, how to deal with it?
You can't do it like that, best solution would be to use dependency injection for $db.
That way you can mock only DB like this...
$dbMock = m::mock('DB');
$dbMock->shouldReceive('data')
->once()
->andReturn(true);
Or you can keep you constructor like this (without DI), but you will have to mock that constructor also.
You can use Mockery by creating an "instance mock" for the DB class like this:
$dbMock = Mockery::mock('overload:MyNamespace\DB');
This will "intercept" when a new instance of the DB class is created and the $dbMock will be used instead. When the $dbMock is created you just need to add an expectation declaration for the given method:
$dbMock->shouldReceive('data')
->once()
->andReturn(true);
I'm having some confusion with the adapter pattern and am wondering if it is the right tool for what I'm trying to accomplish.
Basically, I'm trying to get a class written by another developer to conform to an interface that I've written while also retaining the other methods from that class.
So I've written the following interface for a container object:
interface MyContainerInterface
{
public function has($key);
public function get($key);
public function add($key, $value);
public function remove($key);
}
I've also written an adapter that implements that interface:
class OtherContainerAdapter implements MyContainerInterface
{
protected $container;
public function __construct(ContainerInteface $container) {
$this->container = $container;
}
public function has($key) {
$this->container->isRegistered($key);
}
...
}
And am using it in my class as follows:
class MyClass implements \ArrayAccess
{
protected $container;
public function __construct(MyContainerInterface $container) {
$this->setContainer($container);
}
public function offsetExists($key) {
$this->container->has($key);
}
...
}
Then my application uses the class as so:
$myClass = new MyClass(new OtherContainerAdapter(new OtherContainer));
The issue I'm having is that in order to use the methods from the adapter I have to write the following:
$myClass->getContainer()->getContainer()->has('some_key');
When ideally it would just be:
$myClass->getContainer()->has('some_key');
$myClass->getContainer()
should return an instance of MyContainerInterface and that has a has() function. It shouldn't have a getContainer() function.
I don't think you need the Adapter Pattern for this. It looks to me like you're after a polymorphic solution, which can be accomplished by simply using an abstract class. No adapter needed.
The interface
interface MyContainerInterface
{
public function has($key);
public function get($key);
public function add($key, $value);
public function remove($key);
}
Then the abstract base class:
class MyContainerBaseClass implements MyContainerInterface, \ArrayAccess
{
public function offsetExists($key) {
$this->has($key);
}
...
}
Then, the sub-class from the other developer:
class ClassByOtherDeveloper extends MyContainerBaseClass
{
public function has($key) {
$this->isRegistered($key);
}
//you also need to implement get(), add(), and remove() since they are still abstract.
...
}
You can use it in your application like this:
$object = new ClassByOtherDeveloper();
$x = $object->has('some_key');
I'm assuming the isRegistered method lives in the implementation from the other developer.
To make it truly polymorphic you wouldn't hard-code the class name, but you'd use a variable that could come from a config file, database, or a Factory.
For example:
$className = "ClassByOtherDeveloper"; //this could be read from a database or some other dynamic source
$object = new $className();
$x = $object->has('some_key');
I am looking for the best way to go about testing the following static method (specifically using a Doctrine Model):
class Model_User extends Doctrine_Record
{
public static function create($userData)
{
$newUser = new self();
$newUser->fromArray($userData);
$newUser->save();
}
}
Ideally, I would use a mock object to ensure that fromArray (with the supplied user data) and save were called, but that's not possible as the method is static.
Any suggestions?
Sebastian Bergmann, the author of PHPUnit, recently had a blog post about Stubbing and Mocking Static Methods. With PHPUnit 3.5 and PHP 5.3 as well as consistent use of late static binding, you can do
$class::staticExpects($this->any())
->method('helper')
->will($this->returnValue('bar'));
Update: staticExpects is deprecated as of PHPUnit 3.8 and will be removed completely with later versions.
There is now the AspectMock library to help with this:
https://github.com/Codeception/AspectMock
$this->assertEquals('users', UserModel::tableName());
$userModel = test::double('UserModel', ['tableName' => 'my_users']);
$this->assertEquals('my_users', UserModel::tableName());
$userModel->verifyInvoked('tableName');
I would make a new class in the unit test namespace that extends the Model_User and test that. Here's an example:
Original class:
class Model_User extends Doctrine_Record
{
public static function create($userData)
{
$newUser = new self();
$newUser->fromArray($userData);
$newUser->save();
}
}
Mock Class to call in unit test(s):
use \Model_User
class Mock_Model_User extends Model_User
{
/** \PHPUnit\Framework\TestCase */
public static $test;
// This class inherits all the original classes functions.
// However, you can override the methods and use the $test property
// to perform some assertions.
}
In your unit test:
use Module_User;
use PHPUnit\Framework\TestCase;
class Model_UserTest extends TestCase
{
function testCanInitialize()
{
$userDataFixture = []; // Made an assumption user data would be an array.
$sut = new Mock_Model_User::create($userDataFixture); // calls the parent ::create method, so the real thing.
$sut::test = $this; // This is just here to show possibilities.
$this->assertInstanceOf(Model_User::class, $sut);
}
}
Found the working solution, would to share it despite the topic is old.
class_alias can substitute classes which are not autoloaded yet (works only if you use autoloading, not include/require files directly).
For example, our code:
class MyClass
{
public function someAction() {
StaticHelper::staticAction();
}
}
Our test:
class MyClassTest
{
public function __construct() {
// works only if StaticHelper is not autoloaded yet!
class_alias(StaticHelperMock::class, StaticHelper::class);
}
public function test_some_action() {
$sut = new MyClass();
$myClass->someAction();
}
}
Our mock:
class StaticHelperMock
{
public static function staticAction() {
// here implement the mock logic, e.g return some pre-defined value, etc
}
}
This simple solution doesn't need any special libs or extensions.
Mockery's Alias functionality can be used to mock public static methods
http://docs.mockery.io/en/latest/reference/creating_test_doubles.html#creating-test-doubles-aliasing
Another possible approach is with the Moka library:
$modelClass = Moka::mockClass('Model_User', [
'fromArray' => null,
'save' => null
]);
$modelClass::create('DATA');
$this->assertEquals(['DATA'], $modelClass::$moka->report('fromArray')[0]);
$this->assertEquals(1, sizeof($modelClass::$moka->report('save')));
One more approach:
class Experiment
{
public static function getVariant($userId, $experimentName)
{
$experiment = self::loadExperimentJson($experimentName):
return $userId % 10 > 5; // some sort of bucketing
}
protected static function loadExperimentJson($experimentName)
{
// ... do something
}
}
In my ExperimentTest.php
class ExperimentTest extends \Experiment
{
public static function loadExperimentJson($experimentName)
{
return "{
"name": "TestExperiment",
"variants": ["a", "b"],
... etc
}"
}
}
And then I would use it like so:
public function test_Experiment_getVariantForExperiment()
{
$variant = ExperimentTest::getVariant(123, 'blah');
$this->assertEquals($variant, 'a');
$variant = ExperimentTest::getVariant(124, 'blah');
$this->assertEquals($variant, 'b');
}
Testing static methods is generally considered as a bit hard (as you probably already noticed), especially before PHP 5.3.
Could you not modify your code to not use static a method ? I don't really see why you're using a static method here, in fact ; this could probably be re-written to some non-static code, could it not ?
For instance, could something like this not do the trick :
class Model_User extends Doctrine_Record
{
public function saveFromArray($userData)
{
$this->fromArray($userData);
$this->save();
}
}
Not sure what you'll be testing ; but, at least, no static method anymore...