PHP & Web Development Blogs

Hey there! This reading is not going to be a technical one. Instead, it's just a little portion of information that you might have not known before. I once worked for a project that did currency exchanges. As you probably know, currencies have 3-letter codes (ISO 4217), and I asked myself if there's a currency with code "PHP".

PHP: Philippine peso! In Philippines you can code PHP for PHP!


But there's more to it.. "PHP: Prvi Hrvatski Pištolj" stands for "first Croatian pistol". Next time someone tells me that it's too easy to shoot your own leg with PHP, I'll definitely agree.
If you don't believe me - checkout these 10 most common mistakes PHP programmers make from Toptal!

Or checkout Eric Wastl's list of things in PHP that make him sad. Or these three weird facts about PHP that you might not have known. The thing is PHP is a great programming language for building web applications, but... it's not without it's quirks.

___What else does PHP stand for???___

Project Honey Pot - system targeted at spammers and email harversters.

Pigeonhole principle - if n items are put into m containers, with n > m, then at least one container must contain more than one item. Mathematicians can be even more weird then programmers, can't they? And remember, programmers can right something like if (true == false)...

PHP has even more meanings, see this wikipedia page) for reference and havePHun!

INTRO

If you are working as a PHP software developer, there is an extremely high chance that all of your application, you’re currently working on, using frameworks of any kind.
PHP community developers of all levels worship frameworks since there are big historical and practical reasons for that.

Historical reasons

Since early PHP versions, developers were disreputable because not everybody considered PHP as a programming language, similar to JavaScript a couple of years ago. While strong type language existed decades ago, PHP continues to be soft type since now, only in version 7 basic types were introduced. There is also a matter of the fact that you can script in PHP without using a single object.

But that opened a space for frameworks to step in and introduce themselves as a tool or standard which will shape projects, give them right and order, introduce structure and rules.
And finally, they did. Frameworks are good examples of nice structures, using all available new features PHP offers with every version, enforcing some good practice, etc.

Practical reasons

The framework offers a lot of common problems already solved. They offer a nice ecosystem for other developers to contribute and plug their components. There is a lot of online resources for learning and stay updated about any particular framework. Also, what every framework community tries very hard, is to make setup and usage easy.

WHEN PHP FRAMEWORKS SUCKS

I recently had the opportunity to give a talk on a conference and one meetup about why PHP framework sometimes sucks. Sometimes things we see in framework tutorials does not seem to be very much aligned with some object-oriented standards we are striving to enforce, and with basic clean code guidelines. On the other hand, there is nothing wrong with using a framework, if you use it right.

This article is the first "pilot" article in this series. In every new blog in this series, we will go more in-depth about every specific topic I covered during my presentation.
I'm very excited to share this knowledge, as I saw many developers suffer from bonded-to-framework disease.

https://twitter.com/damnjan/status/1058306144458956800

I won’t spend much time here on any particular framework discussion. This series will be just a guide on how to unbind yourself from frameworks and use them as a tool, instead of being independent.

**Here is the link to the presentation slides.**

As you all know, Laravel Eloquent Relationships are powerful and easy methods introduced by Laravel for helping developers to reduce the complexity when connecting with multiple tables. While connecting with multiple tables, this method is very easy for developers for creating the application

Here you can see the next three methods of the eloquent relationships:
   
. Has Many Through Relationship
    . One to Many Polymorphic
    . Many to many Polymorphic

HAS MANY THROUGH ELOQUENT RELATIONSHIP

Has many through is a little bit complicated while understanding. I will provide a shortcut method to provide access data of another mode relationship. We will create a user table, post table, and country table and they will be interconnected with each other.

Here we will see Many through relationship will use hasManyThrough() for the relation

Create Migrations

Users table

 Schema::create('users', function (Blueprint $table) {

 $table->increments('id');

 $table->string('name');

 $table->string('email')->unique();

 $table->string('password');

 $table->integer('country_id')->unsigned();

 $table->rememberToken();

 $table->timestamps();

 $table->foreign('country_id')->references('id')->on('countries')

 ->onDelete('cascade');

});

Posts table

Schema::create('posts', function (Blueprint $table) {

 $table->increments('id');

 $table->string("name");

 $table->integer('user_id')->unsigned();

 $table->timestamps();

 $table->foreign('user_id')->references('id')->on('users')

 ->onDelete('cascade');

});

Countries table

Schema::create('countries', function (Blueprint $table) {

 $table->increments('id');

 $table->string('name');

 $table->timestamps();

});

Create Models

Country Model

<?php


namespace App;

use Illuminate\Database\Eloquent\Model;


class Country extends Model

{

 public function posts(){

 return $this->hasManyThrough(

 Post::class,

 User::class,

 'country_id', 
 'user_id', 
 'id', 
 'id' 
 );

 }

}

Now we can retrieve records by

$country = Country::find(1); 

dd($country->posts);

ONE TO MANY POLYMORPHIC RELATIONSHIP

One to many polymorphic relationships used one model belongs to another model on a single file. For example, we will have tweets and blogs, both having the comment system. So we need to add the comments. Then we can manage both in a single table


Here we will use sync with a pivot table, create records, get all data, delete, update, and everything related to one too many relationships.

Now I will show one too many polymorphic will use morphMany() and morphTo() for relation.

Create Migrations

Posts table

Schema::create('posts', function (Blueprint $table) {

 $table->increments('id');

 $table->string("name");

 $table->timestamps();

});

Videos Table

Schema::create('videos', function (Blueprint $table) {

 $table->increments('id');

 $table->string("name");

 $table->timestamps();

});

Comments Table

Schema::create('comments', function (Blueprint $table) {

 $table->increments('id');

 $table->string("body");

 $table->integer('commentable_id');

 $table->string("commentable_type");

 $table->timestamps();

});

Create Models

Post Model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;


class Post extends Model

{

 

 public function comments(){

 return $this->morphMany(Comment::class, 'commentable');

 }

}

Video Model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;


class Video extends Model{

 

 public function comments(){

 return $this->morphMany(Comment::class, 'commentable');

 }

}

Comment Model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Comment extends Model{

 

 public function commentable(){

 return $this->morphTo();

 }

}

Create Records

$post = Post::find(1); 

$comment = new Comment;

$comment->body = "Hi Harikrishnan";

$post->comments()->save($comment);


$video = Video::find(1); 

$comment = new Comment;

$comment->body = "Hi Harikrishnan";

$video->comments()->save($comment);

Now we can retrieve records

$post = Post::find(1); 

dd($post->comments);



$video = Video::find(1); 

dd($video->comments);

MANY TO MANY POLYMORPHIC RELATIONSHIPS

Many to many polymorphic is also a little bit complicated like above. If we have a tweet, video and tag table, we need to connect each table like every tweet and video will have multiple persons to tag. And for each and every tag there will be multiple tweet or videos.

Here we can understand the creating of many to many polymorphic relationships, with a foreign key schema of one to many relationships, use sync with a pivot table, create records, attach records, get all records, delete, update, where condition and etc..


Here morphToMany() and morphedByMany() will be used for many to many polymorphic relationships

Creating Migrations

Posts Table

Schema::create('posts', function (Blueprint $table) {

 $table->increments('id');

 $table->string("name");

 $table->timestamps();

});

Videos Table

Schema::create('videos', function (Blueprint $table) {

 $table->increments('id');

 $table->string("name");

 $table->timestamps();

});

Tags table

Schema::create('tags', function (Blueprint $table) {

 $table->increments('id');

 $table->string("name");

 $table->timestamps();

});

Taggables table

Schema::create('taggables', function (Blueprint $table) {

 $table->integer("tag_id");

 $table->integer("taggable_id");

 $table->string("taggable_type");

});

Creating ModelsPost Model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Post extends Model

{

 

 public function tags(){

 return $this->morphToMany(Tag::class, 'taggable');

 }

}

Video Model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Video extends Model

{

 

 public function tags(){

 return $this->morphToMany(Tag::class, 'taggable');

 }

}

Tag Model

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Tag extends Model

{

 

 public function posts(){

 return $this->morphedByMany(Post::class, 'taggable');

 }



 

 public function videos(){

 return $this->morphedByMany(Video::class, 'taggable');

 }

}

Creating Records

$post = Post::find(1); 
$tag = new Tag;
$tag->name = "Hi Harikrishnan";
$post->tags()->save($tag);


$video = Video::find(1); 
$tag = new Tag;
$tag->name = "Vishnu";
$video->tags()->save($tag);


$post = Post::find(1); 
$tag1 = new Tag;
$tag1->name = "Kerala Blasters";
$tag2 = new Tag;
$tag2->name = "Manajapadda";
$post->tags()->saveMany([$tag1, $tag2]);


$video = Video::find(1); 
$tag1 = new Tag;
$tag1->name = "Kerala Blasters";
$tag2 = new Tag;
$tag2->name = "Manajappada";
$video->tags()->saveMany([$tag1, $tag2]);


$post = Post::find(1); 
$tag1 = Tag::find(3);
$tag2 = Tag::find(4);
$post->tags()->attach([$tag1->id, $tag2->id]);


$video = Video::find(1); 
$tag1 = Tag::find(3);
$tag2 = Tag::find(4);
$video->tags()->attach([$tag1->id, $tag2->id]);


$post = Post::find(1); 
$tag1 = Tag::find(3);
$tag2 = Tag::find(4);
$post->tags()->sync([$tag1->id, $tag2->id]);


$video = Video::find(1); 
$tag1 = Tag::find(3);
$tag2 = Tag::find(4);
$video->tags()->sync([$tag1->id, $tag2->id]);

Now we can retrieve records

$post = Post::find(1); 
dd($post->tags);


$video = Video::find(1); 
dd($video->tags)


$tag = Tag::find(1);
dd($tag->posts);


$tag = Tag::find(1);
dd($tag->videos);

Hence we completed all the relationships. In the above blog how has many through relationship, one to many polymorphic relationships and many to many polymorphic are working. This feature is introduced from Laravel 5.0 onwards and till the current version. Without the model, we can’t able to do this relationship. If we are using an eloquent relationship it will be very useful while developing an application.

Hi Guys,

I am sharing you a standalone class for managing a session based cart system. In this class I have provided multiple methods for adding, updating and deleting the products. and By using this class you may manage multiple cart objects with different data only you need to pass a different key in constructor of that class.

Let me share you the How can we use that Class:

Include The cart class

require 'PhpKart.class.php';

Create a Cart Object initializing the Cart base key name, by using different keys we can manage multiple cart data in a same project , like main cart or wishlist

$obj1 = new PhpKart("MainCart");

Here Maincart is the keyname in which $obj1 insert/modify/delete the data

Adding any product inside cart

$obj1->add_to_cart($product_id=123,$quantity=2,$product_information=array("product_name"=>"Tomato","Price"=>20));

Where parameter1 is product, id,parameter 2 is quantity, and Parameter 3 is product information Array

Now If we want to update the quantity in product_id=123 with quantity 5 then use following:

$obj1->add_to_cart($product_id=123,$quantity=5);

Here we did not pass the information array again because no matter you pass or not if the product information is already added in the cart then if won't be affected So no ned to pass this, only pass product id and its Quantity

If we want to add another product:

$obj1->add_to_cart($product_id=145,$quantity=3,$product_information=array("product_name"=>"Potato","Price"=>30));

Now we have a case what if our product is already having some quantity and we want to increase into it or decrease into it, Then to retrieve the already added product information, using AlreadyExists method by passing product id,it will return array if it exists and it will return boolean false if not exists:

$already_exists=$obj1->AlreadyExists($product_id=145); 
if($already_exists !== false )
{
print_r($already_exists);
}

If we want to remove any product from cart:

$obj1->remove_from_cart($product_id=145);

If we want to get all products from the current cart

print_r( $obj1->getAllItems() );

It will return you an array with all the items exist in the current cart

Getting all item's count inside the current cart

echo $obj1->getTotalItems(); 

If we want to get calculate total amount in the current cart

echo $obj1->getCartTotalAmount($priceKeyName='Price')

Note: In the above snippet we need to provide teh same key name which we have used for product price in project information array at the time of adding items in cart array, and need to take the same key name in all the products inserting in Same Cart

If we want to clear/reset the current cart then use following:

$obj1->clear_cart(); 

Now if we want to save some other user interested items separately which use likes but don't want to buy now so that items can be Add into wishlist So we need to create new object with different cart ket name and that list will be manage separately using it's object. Like Following:

Create new Object by passing different Key

$obj2=new PhpKart("MyWishlist"); 

Add a new item to $obj2 object containing the items user want to add in his/her wishlist

$obj2->add_to_cart($product_id=159,$quantity=8,$product_information=array("product_name"=>"Baby Toy","Price"=>100));

Show the total cart Amount

echo $obj2->getCartTotalAmount("Price"); 

Full Source Code

Following is the full code for that cart managing Class . Just create a file named PhpKart.class.php and add following code in it:

<?php 
if(!session_id()){
 @session_start();
}


class PhpKart{

private $cart_key;

public function __construct($CartkeyName)
{
$this->cart_key=$CartkeyName;
}
public function add_to_cart($product_id,$quantity='1',$product_information=array())
{
$_SESSION[$this->cart_key][$product_id]['product_id']=$product_id;
$_SESSION[$this->cart_key][$product_id]['quantity']=$quantity;
if(!isset($_SESSION[$this->cart_key][$product_id]['product_information']) && !empty($product_information)){
$_SESSION[$this->cart_key][$product_id]['product_information']=$product_information;
}
}
public function remove_from_cart($product_id)
{
unset($_SESSION[$this->cart_key][$product_id]);
}
public function clear_cart()
{
unset($_SESSION[$this->cart_key]);
}
public function getTotalItems()
{
return count($_SESSION[$this->cart_key]);
}
public function getCartTotalAmount($price_key_name)
{
$total=0;
foreach($_SESSION[$this->cart_key] as $row)
{
$total += ($row['product_information'][$price_key_name]*$row['quantity']);
}

return $total;
}
public function AlreadyExists($product_id)
{
 if (isset($_SESSION[$this->cart_key][$product_id]))
 {
	return $_SESSION[$this->cart_key][$product_id];
 }
 else
 {
	return false;
 }
}
public function getAllItems()
{
return $_SESSION[$this->cart_key];
}


}

?>

Every time I see this

$users = [new User(), new User()];

I see a lost opportunity to use Iterator.

Why Iterators?

Collections are an awesome way to organize your previously no-named array. There is a couple of reasons why you should use iterators. One of reason stays for behavior, you can specify exact behavior on standard calls such as next, current, valid etc. Other reason could be that you want to ensure that collection contains an only specific type of an object.

Understand a suffer from using an array of unknown value types.
Very common in the PHP world arrays are used to store all kind of data, in many dimensions in many nested forms. Arrays introduced infinite flexibility to the developer, but because of that, they become very evil.

Example:

- Your function (getUsers) returns an array of User objects.
- Another function (setUsersToActiveState) using getUsers output array and set all users active status to true.
- setUsersToActiveState loop through the array and expect to call a specific method on array item. For example, the method name is getActiveStatus.
- If given array is an array of desired objects which have a callable method getActiveStatus, all fine. But if not exception will be thrown.
- How we can ensure that given array is always an array of objects of a specific type?

public function getUsers(): array
{
 
 return $userArray;
}

public function setUsersToActiveState()
{
 $users = $this->getUsers();
 
 foreach ($users as $user) {
 if(!$user->getActiveStatus()) {
 $user->setActiveStatus(true);
 }
 }
}

There immediately two problems occurred.
    . One is the problem of type. Our IDE doesn't know what's inside array of $users, so because of that IDE can't suggest us how to use $user element. (I put this comment block above foreach, it works for phpStorm and I guess for some other IDEs)
    . Your colleagues! How they possibly know what's inside array if there is no any hint.
    . Bonus problem, getUsers can return literally any array and there won't be warning in the system.

Solution

class UsersCollection implements \IteratorAggregate
{
 
 private $users = [];

 public function getIterator() : UserIterator
 {
 return new UserIterator($this);
 }

 public function getUser($position)
 {
 if (isset($this->users[$position])) {
 return $this->users[$position];
 }

 return null;
 }

 public function count() : int
 {
 return count($this->users);
 }

 public function addUser(User $users)
 {
 $this->users[] = $users;
 }
}

class UserIterator implements \Iterator
{
 
 private $position = 0;

 
 private $userCollection;

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

 public function current() : User
 {
 return $this->userCollection->getUser($this->position);
 }

 public function next()
 {
 $this->position++;
 }

 public function key() : int
 {
 return $this->position;
 }

 public function valid() : bool
 {
 return !is_null($this->userCollection->getUser($this->position));
 }

 public function rewind()
 {
 $this->position = 0;
 }
}

Tests

Off course there is the tests to ensure that our Collection and Iterator works like a charm. For this example I using syntax for PHPUnit framework.

class UsersCollectionTest extends TestCase
{
 
 public function testUsersCollectionShouldReturnNullForNotExistingUserPosition()
 {
 $usersCollection = new UsersCollection();

 $this->assertEquals(null, $usersCollection->getUser(1));
 }

 
 public function testEmptyUsersCollection()
 {
 $usersCollection = new UsersCollection();

 $this->assertEquals(new UserIterator($usersCollection), $usersCollection->getIterator());

 $this->assertEquals(0, $usersCollection->count());
 }

 
 public function testUsersCollectionWithUserElements()
 {
 $usersCollection = new UsersCollection();
 $usersCollection->addUser($this->getUserMock());
 $usersCollection->addUser($this->getUserMock());

 $this->assertEquals(new UserIterator($usersCollection), $usersCollection->getIterator());
 $this->assertEquals($this->getUserMock(), $usersCollection->getUser(1));
 $this->assertEquals(2, $usersCollection->count());
 }

 private function getUserMock()
 {
 }
}


class UserIteratorTest extends MockClass
{
 
 public function testCurrent()
 {
 $iterator = $this->getIterator();
 $current = $iterator->current();

 $this->assertEquals($this->getUserMock(), $current);
 }

 
 public function testNext()
 {
 $iterator = $this->getIterator();
 $iterator->next();

 $this->assertEquals(1, $iterator->key());
 }

 
 public function testKey()
 {
 $iterator = $this->getIterator();

 $iterator->next();
 $iterator->next();

 $this->assertEquals(2, $iterator->key());
 }

 
 public function testValidIfItemInvalid()
 {
 $iterator = $this->getIterator();

 $iterator->next();
 $iterator->next();
 $iterator->next();

 $this->assertEquals(false, $iterator->valid());
 }

 
 public function testValidIfItemIsValid()
 {
 $iterator = $this->getIterator();

 $iterator->next();

 $this->assertEquals(true, $iterator->valid());
 }

 
 public function testRewind()
 {
 $iterator = $this->getIterator();

 $iterator->rewind();

 $this->assertEquals(0, $iterator->key());
 }

 private function getIterator() : UserIterator
 {
 return new UserIterator($this->getCollection());
 }

 private function getCollection() : UsersCollection
 {
 $userItems[] = $this->getUserMock();
 $userItems[] = $this->getUserMock();

 $usersCollection = new UsersCollection();

 foreach ($userItems as $user) {
 $usersCollection->addUser($user);
 }

 return $usersCollection;
 }

 private function getUserMock()
 {
 }
}

Usage

public function getUsers(): UsersCollection
{
 $userCollection = new UsersCollection();
 
 foreach ($whatIGetFromDatabase as $user) {
 $userCollection->addUser($user);
 }
 return $userCollection;
}

public fucntion setUsersToActiveState()
{
 $users = $this->getUsers();

 foreach ($users as $user) {
 if(!$user->getActiveStatus()) {
 $user->setActiveStatus(true);
 }
 }
}

As you can see setUsersToActiveState remains the same, we only do not need to specify for our IDE or collagues what type $users variable is.

Extending functionalities

Believe or not you can reuse this two objects and just change names of variables to fit most of the needs. But if you want any more complex functionality, than feel free to add it in iterator or collection.

Example 1

For example, let's say that userCollection accepts only users with age more than 18. Implementation will happen in UsersCollection class in the method addUser.

 public function addUser(User $users)
 {
 if ($user->getAge() > 18) {
 $this->users[] = $users;
 } 
 }

Example 2

You need to add bulk users. Then you can expand your userCollection with additional method addUsers and it might look like this.

 public function addUsers(array $users)
 {
 foreach($users as $user) {
 $this->addUser(User $users);
 }
 }