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Showing 1 to 5 of 26 blog articles.
25824 views · 5 years ago
PHP CHAT WITH SOCKETS

Hey Friends,

I am sharing a very interesting blog on how to create a chat system in php without using ajax. As we all know ajax based chat system in php is not a good solution
because itincreases the server load and redundant xhr calls on our server.

Instead, I am going to use sockets for incoming messages from and send messages to another user. So lets try them out using the following steps:


Step 1: Cross check in php.ini that sockets extension is enabled


;extension=sockets
extension=sockets


Step 2: Create server.php file


This file will handle the incoming and outgoing messages on sockets, Add following variables in top of the file:

$host = 'localhost';
$port = '9000';
$null = NULL; 


Step 3: After it add helper methods


The following code for handshake with new incoming connections and encrypt and decrypt messages incoming and outgoing over sockets:

function send_message($msg)
{
global $clients;
foreach($clients as $changed_socket)
{
@socket_write($changed_socket,$msg,strlen($msg));
}
return true;
}
function unmask($text) {
$length = ord($text[1]) & 127;
if($length == 126) {
$masks = substr($text, 4, 4);
$data = substr($text, 8);
}
elseif($length == 127) {
$masks = substr($text, 10, 4);
$data = substr($text, 14);
}
else {
$masks = substr($text, 2, 4);
$data = substr($text, 6);
}
$text = "";
for ($i = 0; $i < strlen($data); ++$i) {
$text .= $data[$i] ^ $masks[$i%4];
}
return $text;
}
function mask($text)
{
$b1 = 0x80 | (0x1 & 0x0f);
$length = strlen($text);

if($length <= 125)
$header = pack('CC', $b1, $length);
elseif($length > 125 && $length < 65536)
$header = pack('CCn', $b1, 126, $length);
elseif($length >= 65536)
$header = pack('CCNN', $b1, 127, $length);
return $header.$text;
}
function perform_handshaking($receved_header,$client_conn, $host, $port)
{
$headers = array();
$lines = preg_split("/

/", $receved_header);
foreach($lines as $line)
{
$line = chop($line);
if(preg_match('/\A(\S+): (.*)\z/', $line, $matches))
{
$headers[$matches[1]] = $matches[2];
}
}
$secKey = $headers['Sec-WebSocket-Key'];
$secAccept = base64_encode(pack('H*', sha1($secKey . '258EAFA5-E914-47DA-95CA-C5AB0DC85B11')));
$upgrade = "HTTP/1.1 101 Web Socket Protocol Handshake

" .
"Upgrade: websocket

" .
"Connection: Upgrade

" .
"WebSocket-Origin: $host

" .
"WebSocket-Location: ws://$host:$port/php-ws/chat-daemon.php

".
"Sec-WebSocket-Accept:$secAccept



";
socket_write($client_conn,$upgrade,strlen($upgrade));
}


Step 4: Now add following code to create bind and listen tcp/ip sockets:


$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);
socket_bind($socket, 0, $port);
socket_listen($socket);
$clients = array($socket);


Ok now a endless loop that will use for handeling incominga nd send messages:

while (true) {
$changed = $clients;
socket_select($changed, $null, $null, 0, 10);

if (in_array($socket, $changed)) {
$socket_new = socket_accept($socket); $clients[] = $socket_new;
$header = socket_read($socket_new, 1024); perform_handshaking($header, $socket_new, $host, $port);
socket_getpeername($socket_new, $ip); $response = mask(json_encode(array('type'=>'system', 'message'=>$ip.' connected'))); send_message($response);
$found_socket = array_search($socket, $changed);
unset($changed[$found_socket]);
}

foreach ($changed as $changed_socket) {

while(socket_recv($changed_socket, $buf, 1024, 0) >= 1)
{
$received_text = unmask($buf); $tst_msg = json_decode($received_text, true); $user_name = $tst_msg['name']; $user_message = $tst_msg['message']; $user_color = $tst_msg['color'];
$response_text = mask(json_encode(array('type'=>'usermsg', 'name'=>$user_name, 'message'=>$user_message, 'color'=>$user_color)));
send_message($response_text); break 2; }

$buf = @socket_read($changed_socket, 1024, PHP_NORMAL_READ);
if ($buf === false) { $found_socket = array_search($changed_socket, $clients);
socket_getpeername($changed_socket, $ip);
unset($clients[$found_socket]);

$response = mask(json_encode(array('type'=>'system', 'message'=>$ip.' disconnected')));
send_message($response);
}
}
}
socket_close($socket);


So you are ready with server side socket program, Now its time to move on front side where we will implement w3c provided client side Web Socket Apis,

Step 5: create a file named index.php for frontend usage with following initial code


$host = 'localhost';
$port = '9000';
$subfolder = "php_ws/";
$colors = array('#007AFF','#FF7000','#FF7000','#15E25F','#CFC700','#CFC700','#CF1100','#CF00BE','#F00');
$color_pick = array_rand($colors);
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<div class="chat-wrapper">
<div id="message-box"></div>
<div class="user-panel">
<input type="text" name="name" id="name" placeholder="Your Name" maxlength="15" />
<input type="text" name="message" id="message" placeholder="Type your message here..." maxlength="100" />
<button id="send-message">Send</button>
</div>
</div>
</body>
</html>


Now add some basic styling in the head section using following code:

<style type="text/css">
.chat-wrapper {
font: bold 11px/normal 'lucida grande', tahoma, verdana, arial, sans-serif;
background: #00a6bb;
padding: 20px;
margin: 20px auto;
box-shadow: 2px 2px 2px 0px #00000017;
max-width:700px;
min-width:500px;
}
#message-box {
width: 97%;
display: inline-block;
height: 300px;
background: #fff;
box-shadow: inset 0px 0px 2px #00000017;
overflow: auto;
padding: 10px;
}
.user-panel{
margin-top: 10px;
}
input[type=text]{
border: none;
padding: 5px 5px;
box-shadow: 2px 2px 2px #0000001c;
}
input[type=text]#name{
width:20%;
}
input[type=text]#message{
width:60%;
}
button#send-message {
border: none;
padding: 5px 15px;
background: #11e0fb;
box-shadow: 2px 2px 2px #0000001c;
}
</style>


Ok Style is all set now need to add a jquery script and create web socket object and handle all events on it as following code need to add before closing of bosy tag:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script language="javascript" type="text/javascript">
var msgBox = $('#message-box');
var wsUri = "ws://".$host.":".$port."/php-ws/server.php";
websocket = new WebSocket(wsUri);

websocket.onopen = function(ev) { msgBox.append('<div class="system_msg" style="color:#bbbbbb">Welcome to my "Chat box"!</div>'); }
websocket.onmessage = function(ev) {
var response = JSON.parse(ev.data);
var res_type = response.type; var user_message = response.message; var user_name = response.name; var user_color = response.color; switch(res_type){
case 'usermsg':
msgBox.append('<div><span class="user_name" style="color:' + user_color + '">' + user_name + '</span> : <span class="user_message">' + user_message + '</span></div>');
break;
case 'system':
msgBox.append('<div style="color:#bbbbbb">' + user_message + '</div>');
break;
}
msgBox[0].scrollTop = msgBox[0].scrollHeight; };

websocket.onerror = function(ev){ msgBox.append('<div class="system_error">Error Occurred - ' + ev.data + '</div>'); };
websocket.onclose = function(ev){ msgBox.append('<div class="system_msg">Connection Closed</div>'); };
$('#send-message').click(function(){
send_message();
});

$( "#message" ).on( "keydown", function( event ) {
if(event.which==13){
send_message();
}
});

function send_message(){
var message_input = $('#message'); var name_input = $('#name');
if(message_input.val() == ""){ alert("Enter your Name please!");
return;
}
if(message_input.val() == ""){ alert("Enter Some message Please!");
return;
}
var msg = {
message: message_input.val(),
name: name_input.val(),
color : '<?php echo $colors[$color_pick]; ?>'
};
websocket.send(JSON.stringify(msg));
message_input.val(''); }
</script>


Ok All set, Now need to run the server.php file using following php-cli utility,make sure you have php cli utility installed in your system:

php -q c:\xampp\htdocs\php-ws\server.php


Now you may access the front index.php file via the browser url like following and see a chatbox and connection status, you may use the same url or different browser to check the chat system is working or not.
8874 views · 4 years ago
Laravel Eloquent Relationship Part 2

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.
1010 views · 6 months ago


Linux is an incredibly powerful operating system favored by developers, system administrators, and tech enthusiasts alike. Whether you're just starting your journey with Linux or looking to refresh your knowledge, understanding basic Linux commands is essential for navigating the command line interface (CLI) efficiently. In this beginner's guide, we'll introduce you to some fundamental Linux commands that will help you get started and feel more comfortable in the terminal.

Accessing the Terminal:


Before we dive into the commands, let's briefly discuss how to access the terminal on different Linux distributions:

-GNOME (Ubuntu, Fedora, Debian): Press Ctrl + Alt + T to open the terminal.

-KDE (Kubuntu): Press Alt + F2, type konsole, and press Enter.

-Command Line Interface (CLI) Only (Arch Linux, CentOS): You're already in the terminal!

Basic Navigation:

cd (Change Directory): Use cd followed by the name of the directory to navigate to that directory. For example:
cd Documents 

ls (List Files): Use ls to list the files and directories in the current directory.
ls 

pwd (Print Working Directory): Use pwd to display the full path of the current directory.
pwd 


File Management:

mkdir (Make Directory): Use mkdir followed by the name of the directory to create a new directory.
mkdir my_directory 

touch: Use touch followed by the name of the file to create a new empty file.
touch my_file.txt 

cp (Copy): Use cp followed by the source file and destination to copy files.
cp source_file.txt destination_directory/ 

mv (Move/Rename): Use mv followed by the source and destination to move or rename files.
mv old_name.txt new_name.txt 

rm (Remove): Use rm followed by the file name to delete files. Be careful as this action is irreversible.
rm unwanted_file.txt 


Working with Text:

cat (Concatenate): Use cat followed by the file name to display the contents of a file.
cat my_file.txt 

nano or vim (Text Editors): Use nano or vim followed by the file name to edit a file in the terminal.
nano my_file.txt 

grep (Global Regular Expression Print): Use grep followed by a search term and file name to search for a specific pattern in a file.
grep "pattern" my_file.txt 


System Information:

uname (Unix Name): Use uname to display system information.
uname -a 

df (Disk Free): Use df to display disk space usage.
df -h 

top or htop (Process Monitoring): Use top or htop to display real-time system resource usage.
top 


Conclusion:


Mastering basic Linux commands is the first step toward becoming proficient in using the Linux command line interface. In this guide, we've covered some essential commands for navigation, file management, working with text, and obtaining system information. As you continue to explore Linux, you'll discover a vast array of commands and utilities that can help you streamline your workflow and accomplish a wide range of tasks from the terminal. Happy command line exploring!
384 views · 6 months ago


Unit testing is a crucial aspect of modern software development, ensuring that individual units of code function correctly in isolation. In PHP, unit testing helps developers identify bugs early in the development cycle, improve code quality, and facilitate code maintenance. In this comprehensive guide, we'll walk you through the process of creating unit tests in PHP, using popular testing frameworks like PHPUnit.

Why Unit Testing?


Unit testing involves testing individual components or units of code in isolation from the rest of the application. Here are some reasons why unit testing is essential:
   
. Bug Detection: Unit tests help identify bugs and regressions early in the development process, making them easier and cheaper to fix.
   
. Code Quality: Writing unit tests encourages developers to write modular, well-structured, and maintainable code.
   
. Improved Documentation: Unit tests serve as executable documentation, providing clear examples of how individual components of your code should behave.

Getting Started with PHPUnit:


PHPUnit is the most widely used testing framework for PHP. It provides a robust set of features for writing and executing unit tests. Let's dive into how you can get started with PHPUnit:

Installation:


You can install PHPUnit using Composer, the PHP package manager. Simply navigate to your project directory and run the following command:

composer require --dev phpunit/phpunit


This command installs PHPUnit as a development dependency in your project.

Writing Your First Test:


Now that PHPUnit is installed, let's create a simple test case. Create a new directory named tests in your project root, and within that directory, create a file named ExampleTest.php. Here's an example of what your test file might look like:

<?php

use PHPUnit\Framework\TestCase;

class ExampleTest extends TestCase
{
public function testTrueAssertsToTrue()
{
$this->assertTrue(true);
}
}


This test case contains a single test method named testTrueAssertsToTrue, which asserts that true is indeed true.

Running Tests:


To run your tests, simply execute PHPUnit from the command line, pointing it to your test directory. Run the following command in your project root:

vendor/bin/phpunit tests


PHPUnit will discover and execute all test cases within the specified directory, providing detailed feedback on the results.

Writing Testable Code:


Writing testable code is essential for effective unit testing. Here are some best practices to follow:
   
. Separation of Concerns: Ensure that your code follows the principle of separation of concerns, with clear boundaries between different components.
   
. Dependency Injection: Use dependency injection to inject dependencies into your classes, making it easier to replace them with mock objects during testing.
   
. Mocking and Stubbing: Use PHPUnit's mocking and stubbing features to simulate the behavior of dependencies and isolate the code under test.

Advanced Features:


PHPUnit provides a wide range of advanced features for writing comprehensive unit tests. Some notable features include:

-Data Providers: Use data providers to run a test method with multiple sets of data.

-Annotations: PHPUnit supports annotations for marking test methods, setting up fixtures, and configuring test execution.

-Code Coverage: PHPUnit can generate code coverage reports, showing which parts of your codebase are covered by your tests.

Conclusion:


Unit testing is an indispensable practice in modern PHP development, and PHPUnit makes it easy to write and execute unit tests for your codebase. In this guide, we've covered the basics of getting started with PHPUnit, writing testable code, and leveraging advanced features to write comprehensive unit tests. By incorporating unit testing into your development workflow, you can improve code quality, reduce bugs, and build more robust and maintainable PHP applications.
425 views · 6 months ago


Are you looking to dive into the world of relational databases but feeling overwhelmed by the options available? MariaDB might just be the perfect starting point for you. In this beginner's guide, we'll introduce you to MariaDB, an open-source relational database management system (RDBMS) that's renowned for its ease of use, scalability, and robust performance. Whether you're a budding developer, a small business owner, or just curious about databases, this guide will walk you through the basics of MariaDB and get you started on your database journey.

What is MariaDB?


MariaDB is a community-developed, open-source RDBMS that was forked from MySQL in 2009. It's designed to be a drop-in replacement for MySQL, meaning that most MySQL features and commands work seamlessly with MariaDB. This makes it an attractive option for those already familiar with MySQL or looking to migrate from it.

Features of MariaDB:
   

. Open-Source: MariaDB is distributed under the GNU General Public License (GPL), making it freely available for anyone to use, modify, and distribute.
   
. High Performance: MariaDB is optimized for high performance, thanks to its efficient storage engines, query optimizer, and multi-threaded architecture.
   
. Scalability: Whether you're running a small-scale application or managing large-scale deployments, MariaDB can scale to meet your needs.
   
. Security: MariaDB takes security seriously, offering features such as encryption, role-based access control, and secure connections to ensure your data remains safe.
   
. Compatibility: As mentioned earlier, MariaDB strives to maintain compatibility with MySQL, which means you can easily migrate existing MySQL databases to MariaDB with minimal hassle.

Getting Started:


Installation:


Getting started with MariaDB is straightforward. You can install it on various operating systems, including Linux, Windows, and macOS. Here's a basic overview of the installation process:

-Linux: Most Linux distributions offer MariaDB in their official repositories. You can install it using your package manager. For example, on Ubuntu, you can run sudo apt-get install mariadb-server.

-Windows/macOS: MariaDB provides installers for Windows and macOS on their official website. Simply download the installer and follow the on-screen instructions to complete the installation.

Configuration:


Once MariaDB is installed, you'll need to perform some initial configuration steps, such as setting up a root password and securing the installation. This typically involves running a configuration script or accessing the MariaDB command-line interface (CLI).

Creating Databases and Tables:


With MariaDB installed and configured, you can start creating databases and tables to store your data. You can do this using SQL commands or a graphical interface such as phpMyAdmin.

Here's a simple example of creating a database and a table:

CREATE DATABASE my_database;
USE my_database;

CREATE TABLE users (
id INT AUTO_INCREMENT PRIMARY KEY,
username VARCHAR(50) NOT NULL,
email VARCHAR(100) NOT NULL
);


This creates a database named my_database and a table named users with columns for id, username, and email.

Performing Basic Queries:


Once you have your database and tables set up, you can start querying your data using SQL. Here are some basic examples of SQL queries:

-Inserting Data:
INSERT INTO users (username, email) VALUES ('john_doe', '[email protected]');


-Selecting Data:
SELECT * FROM users;


-Updating Data:
UPDATE users SET email = '[email protected]' WHERE username = 'john_doe';


-Deleting Data:
DELETE FROM users WHERE username = 'john_doe';


Conclusion:


MariaDB is an excellent choice for beginners and experienced developers alike who are looking for a powerful, open-source relational database solution. In this guide, we've covered the basics of MariaDB, from installation to performing basic database operations. As you continue to explore MariaDB, you'll discover a wealth of features and capabilities that can help you build robust and scalable applications. So why wait? Dive into MariaDB today and unlock the full potential of relational databases.

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