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Showing 1 to 4 of 4 blog articles.
221 views · 2 weeks ago

![A Beginners Guide To Artificial Intelligence For Web Developers](https:/ /cdn.filestackcontent.com/PT0l0IeCQxOeHrg3fwlH)

Artificial Intelligence has significantly transformed the way we work and interpret information. With technologies such as OCR, machine learning, deep learning, natural language processing, and computer vision; machines are now able to provide greater insights and perform tasks that typically required hours and hours of work from humans.

## What is artificial intelligence?

A.I. or artificial intelligence is the technology that enables machines to perform tasks that usually require human intelligence. But instead of using human brains, A.I. uses different technologies such as computers, or even software algorithms, to perform tasks. Some of the most common A.I. technologies include speech recognition, voice recognition, machine translation, natural language processing, computer vision, and predictive analytics. The term artificial intelligence comes from the combination of artificial and intelligence. While artificial intelligence is a property of the physical world, intelligence is the property of the mind. How does it make sense in Web Development? As mentioned earlier, A.I. has significantly transformed the way we work and interpret information.

## How is AI applied to web development?

In the majority of cases, AI is used to assist a developer in a number of functions: Automatically format existing content, analyze images for semantic meaning Break down complex tasks into smaller pieces Example applications of AI in web development Example image compression algorithms. Tools such as image recognition and machine learning have been key factors in the development of new image processing algorithms. Traditionally, manually processing an image was a lengthy and tedious process, but when computer vision was introduced into the process it drastically decreased the amount of time required to complete this task. Now, programs such as image recognition can identify objects in images and classify them based on both visual and metadata attributes.

## Machine learning

When data is fed into a machine learning algorithm, the machine learns to understand it. For instance, if you provide a machine learning algorithm examples of dogs verses blueberries, the machine will learn to identify what a picture of a blueberry looks like, verses a picture of a dog. Natural Language Processing Natural language processing is a sub-field of machine learning. You can apply natural language processing for reading emails, chatting, or writing blog posts (such as this one!). A good example of natural language processing in action can be found in Microsoft's Cortana. Deep learning This is the most popular type of artificial intelligence today.

## Deep learning

Deep learning algorithms are very similar to how the human brain works, with its built in mechanisms to learn and memorise a vast amount of information. It's these connections that enable machines to be able to recognise patterns and learn from them. An example of this is Google Translate, which recognises more than a 1,000 languages. This isn't an example of AI but it shows how useful these programs can be. Deep learning is one of the hottest technologies in the field of machine learning and this explains why almost all of the major technology companies are pushing these advances forward.

## Natural language processing

For example, your phone can understand you better when you speak to it. If you say “Hey, Siri,” your phone will listen to you and respond to your questions. In general, it means that the system has been trained and is able to better understand the context of what you’re trying to communicate. This type of Natural Language Processing is used in the majority of companies today, including the likes of Google and Apple, to improve the user experience, provide better customer service, and to aid in the effective execution of processes. Machine learning Machine Learning is an extremely powerful technique used to further improve the knowledge of artificial intelligence, as well as to make machines smarter by discovering patterns and generalities in vast amounts of data.

## Computer vision

Computer vision is a technology that has been able to recognize objects in images and video for eons. A popular example is Apple's Siri, which was one of the first software to use computer vision to provide contextual awareness. AI is built on this technology, providing the capability to recognize various images and videos. The industry is still in its infancy, but what we have seen so far has been incredibly incredible. What's amazing is that just a few years ago we thought that vision was completely under our control, but now, it has evolved to understand the nuances of objects.

## Conclusion

**“In the year 2050, the Amazon book you ordered for your Kindle will be delivered by a drone.”**

This futuristic statement by Amazon CEO Jeff Bezos did leave you pondering. But it is one thing to dream about the future and another thing to think about the innovations taking place in the present and how you can exploit them to drive better business results. To make the most of the technologies coming to our everyday lives, we must acquire a knowledge of the AI technology, its features, and its application. Succeeding in today’s competitive and challenging business world, requires a broad set of skills such as coding, business analysis, computer programming, and ecommerce marketing.

[Learn more about AI with our video library](https:/ /nomadphp.com/videos/ai-machine-learning)

1407 views · 6 months ago

![Web Sockets in PHP](https:/ /cdn.filestackcontent.com/uluFRmjARj6zAQWN05PZ)

In his talk **[Websockets in PHP](https:/ /nomadphp.com/video/219/websockets-in-php)**, [John Fransler](https:/ /johnfansler.com/) walks us through the use of WebSockets in PHP.

While discussing bi-directional real-time application development, John notes that PHP is often not invited to the table due to its lack of native support. Of all the possible attempts to bring in PHP on this stage of real-time development, Ratchet, a PHP WebSocket library, comes closest. "[Ratchet](http:/ /socketo.me/) is a loosely coupled PHP library providing developers with tools to create real-time, bi-directional applications between clients and servers over WebSockets."* Ahem!

### Today's dynamic world

In today's dynamic content world of the internet, it is required to serve real-time bi-directional messages between clients and servers. WebSockets are simple, full-duplex, and persistent. They work over Http and are a standard today.

> WebSockets have compatibility with 96.5% of clients globally

There's a very high chance your client has the necessary plumbing to access your content via WebSockets. WebSockets gives the ability to have real-time data on to your clients without the need for polling.

To understand WebSockets, John takes an example of a Javascript client and Ratchet Server. Javascript has everything built in to allow access to a socket. For example, you can use the send method on a WebSocket variable to send a message to the server, or if you want to respond to a message from the server, you use the `OnConnection` method.

While on the Server, John uses Ratchet, which is built on [React PHP](https:/ /reactphp.org/). A server script is then configured and set up to run and listen on a port for incoming HTTP requests. For messages, JSON is used, and to find public methods, a router is set up. He then goes on to instantiate the server-side script in Ratchet.

**There are four functions of a Ratchets message component interface that are used in this example:**

`OnOpen` gets called when a new connection is made.

`OnClose` gets called when a client quits. It's essential to keep an eye on memory management, and essential to keep tidying up as you move through the code.

`OnError` gets called when there is an exception faced by the user.

`OnMessage` gives the text of the JSON message, which is being exchanged with the client.

For Initialization, Jason continues to walk through the example. He shows how one can loop through the clients, both inside the server and outside the server. Outside the server, it’s a feature of React PHP. On database access, and with traditional standard synchronous MySQL in PHP, what usually happens is that it forces the code to wait for the query to return a result and do nothing — Fortunately, with Asynchronous MySQLi, that is not the case.

John gets into the details explaining Variables, References & Pointers. He also gives a demo where a central site has updated information on the Bitcoin and ether prices. A client terminal reflects the last values. Now the client doesn't have to poll the server for new values. When there is a change in the Bitcoin or ether values, the server pushes down the client's update. No polling helps with a lot of overheads and gets closer to real-time.

### Using Supervisord

For Long-running applications - Jason recommends running a supervisord, use proxy to expose the port, and add a site certificate. Supervisord keeps an eye out for the server running the service; it can be used to restart the service and log any service issues. Recommended proxies are AWS load balancer, Nginx, and HA Proxy. For scalability, use multiple smaller WebSocket servers and a smaller number of clients per server used and load balancing. If one has to support a chat feature to allow clients to talk to each other in near real-time, it is recommended to use [Redis](https:/ /redislabs.com/). The Redis server proxies the messages between the server nodes.

The talk concludes with John summarizing best practices on error handling and takes QnA on various aspects of WebSockets such as handling load balancers and asynchronous calls to MSQLi.

The presentation for this video, along with the code, is hosted at [John Curt's GitHub](https:/ /github.com/johncurt). More info about John's current areas of interest can be found on [John's Blog](https:/ /engagedphp.com/).

### [Watch the video now](https:/ /nomadphp.com/video/219/websockets-in-php)

[Related videos](https:/ /nomadphp.com/search/videos?search_query=async)

13406 views · 2 years ago

![PHP CHAT WITH SOCKETS](https://images.ctfassets.net/vzl5fkwyme3u/71dBtxsZPdBnAn8UgQTyRR/75ca0c2ab27af41ffc82b17d1be264d7/AdobeStock_265642631.jpeg?w=1000)

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 it **increases 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

/ /remove semicolon from very start of the extension like

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:

```php

$host = 'localhost'; / /host

$port = '9000'; / /port

$null = NULL; / /null var

```

### 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:

```php

function send_message($msg)

{

global $clients;

foreach($clients as $changed_socket)

{

@socket_write($changed_socket,$msg,strlen($msg));

}

return true;

}

/ /Unmask incoming framed message

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;

}

/ /Encode message for transfer to client.

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;

}

/ /handshake new client.

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')));

/ /hand shaking header

$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:

```php

/ /Create TCP/IP stream socket

$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

/ /reuseable port

socket_set_option($socket, SOL_SOCKET, SO_REUSEADDR, 1);

/ /bind socket to specified host

socket_bind($socket, 0, $port);

/ /listen to port

socket_listen($socket);

/ /create & add listning socket to the list

$clients = array($socket);

```

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

```php

/ /start endless loop, so that our script doesn't stop

while (true) {

/ /manage multiple connections

$changed = $clients;

/ /returns the socket resources in $changed array

socket_select($changed, $null, $null, 0, 10);

/ /check for new socket

if (in_array($socket, $changed)) {

$socket_new = socket_accept($socket); / /accpet new socket

$clients[] = $socket_new; / /add socket to client array

$header = socket_read($socket_new, 1024); / /read data sent by the socket

perform_handshaking($header, $socket_new, $host, $port); / /perform websocket handshake

socket_getpeername($socket_new, $ip); / /get ip address of connected socket

$response = mask(json_encode(array('type'=>'system', 'message'=>$ip.' connected'))); / /prepare json data

send_message($response); / /notify all users about new connection

/ /make room for new socket

$found_socket = array_search($socket, $changed);

unset($changed[$found_socket]);

}

/ /loop through all connected sockets

foreach ($changed as $changed_socket) {

/ /check for any incomming data

while(socket_recv($changed_socket, $buf, 1024, 0) >= 1)

{

$received_text = unmask($buf); / /unmask data

$tst_msg = json_decode($received_text, true); / /json decode

$user_name = $tst_msg['name']; / /sender name

$user_message = $tst_msg['message']; / /message text

$user_color = $tst_msg['color']; / /color

/ /prepare data to be sent to client

$response_text = mask(json_encode(array('type'=>'usermsg', 'name'=>$user_name, 'message'=>$user_message, 'color'=>$user_color)));

send_message($response_text); / /send data

break 2; / /exist this loop

}

$buf = @socket_read($changed_socket, 1024, PHP_NORMAL_READ);

if ($buf === false) { / / check disconnected client

/ / remove client for $clients array

$found_socket = array_search($changed_socket, $clients);

socket_getpeername($changed_socket, $ip);

unset($clients[$found_socket]);

/ /notify all users about disconnected connection

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

send_message($response);

}

}

}

/ / close the listening socket

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

```php

$host = 'localhost'; / /host

$port = '9000'; / /port

$subfolder = "php_ws/"; / /project subfolder name, you may change it with project directory or make it blank

/ /#add trail slash if there is any subfolder defined otherrwise make it blank

$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:

```html

<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:

```html

<script src="https:/ /ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<script language="javascript" type="text/javascript">

/ /create a new WebSocket object.

var msgBox = $('#message-box');

var wsUri = "ws:/ /".$host.":".$port."/php-ws/server.php";

websocket = new WebSocket(wsUri);

websocket.onopen = function(ev) { / / connection is open

msgBox.append('<div class="system_msg" style="color:#bbbbbb">Welcome to my "Chat box"!</div>'); / /notify user

}

/ / Message received from server

websocket.onmessage = function(ev) {

var response = JSON.parse(ev.data); / /PHP sends Json data

var res_type = response.type; / /message type

var user_message = response.message; / /message text

var user_name = response.name; / /user name

var user_color = response.color; / /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; / /scroll message

};

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>'); };

/ /Message send button

$('#send-message').click(function(){

send_message();

});

/ /User hits enter key

$( "#message" ).on( "keydown", function( event ) {

if(event.which==13){

send_message();

}

});

/ /Send message

function send_message(){

var message_input = $('#message'); / /user message text

var name_input = $('#name'); / /user name

if(message_input.val() == ""){ / /empty name?

alert("Enter your Name please!");

return;

}

if(message_input.val() == ""){ / /emtpy message?

alert("Enter Some message Please!");

return;

}

/ /prepare json data

var msg = {

message: message_input.val(),

name: name_input.val(),

color : '<?php echo $colors[$color_pick]; ?>'

};

/ /convert and send data to server

websocket.send(JSON.stringify(msg));

message_input.val(''); / /reset message input

}

</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.

3636 views · 2 years ago

![Underclocking a Website](https://images.ctfassets.net/vzl5fkwyme3u/1gUKgVHV36U4mqgWwwIA8G/1e350cae18d63baa658ce1ce39eaf991/AdobeStock_142796620.jpeg?w=1000)

For those of you not familiar with the concept of underclocking: it's the opposite of overclocking, that is, you don't speed up CPU but instead slow it down..

### What for?

Ask the underclockers, I'm totally not sure. Actually, hanging around the Web these days leaves a feeling that nearly every website out there must have been underclocked, but most of the time it's about tons of unnecessary images, megabytes of javascript (of which hardly a hundred kilobytes gets actually executed), and all that. In this post I will, however, tell you about a server-side approach to underclocking, with a help of our good old friend - the MySQL Database Server.

Today I had a nice chat in my client's development telegram channel. The two other devs, R** and V**, were making a switch of the old image API app to a new MySQL server. A couple of days before that, we have discussed a plan, it was as dumb as possible, just as I like it. Super-simple clear steps that a five-year-old can make. Switch to readonly mode (stop uploads), dump DB, restore the dump on the new server, update database connection details, turn off readonly mode. What could possibly go wrong?

Nothing. Except that it did go wrong. The app that I'm talking about, is a really ancient piece of what is gently called "legacy". Once the app was back to normal again, we noticed a significant slowdown on every page that made use of images. Before that point, I never got to that app and/or its database. I logged in to the MySQL console, and started investigating, at the same point chatting with colleagues.

```

Me: Is that really important that the tables are MyISAM? It's 2018, you know.. There are dozens of queries in queue waiting for table-level locks.

R**: Are they MyISAM? Really?

Me: Yes.. Any objection against converting them to InnoDB? With the current state of the website, with all those tons of Gateway Timeouts, it's not going to make it worse if I do it right now..

```

10 minutes later:

```

Me: Nah, it didn't help a lot.. But, looking at the SHOW PROCESSLIST output, I see something weird. What, do you think, this query does? SELECT LAST_INSERT_ID() FROM images?

R**: ehh... Gets you the last AUTO_INCREMENT id from images table?

Me: Let's play another good news bad news joke.. Good news: you're right, it gets you the last AUTO_INCREMENT id. Bad news: it's not for table, it's for the session. Worse news: this query gets you the last AUTO_INCREMENT id and does it exactly as many times as there are rows in the images table. how many are there?

R**: about 8mln. #@%&! It's sending 8mln rows on every image upload, through the network!

Me: Bingo! 8mln rows, with one and the same integer value in all of them.

R**: Ouch... Aaaand... Before today, it was not an issue. Because the database was on the same server as the application..

Me: Exactly, it used the loopback interface, and now it's using ehternet, which, apparently, doesn't have a super good bandwidth. We don't have a gigabit channel between servers, do we?

R**: No, it's 100 Mbit

Me: Are you fixing the query, BTW?

R**: yeah, man, deploying it...

```

Another 10 minutes later, problem is gone, performance is back to normal.

### What conclusions can one make from this story?

I can think of two at least:

**First: never underestimate legacy code.** The ways it can move to bite you in the ass, are mysterious.

**Second: if you're working with MySQL or another RDBMS, learn SQL**, learn the specific SQL dialect you're using and learn how to trouble shoot issues. In this case, I did not need to look in the PHP code at all in order to help my fellow colleagues out. You can also generalize this principle as "you have to know the tools you're using".

Happy optimizing, folks! Comments appreciated!

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