PHP & Web Development Blogs

In his talk Websockets in PHP, John Fransler 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 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. 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. 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. More info about John's current areas of interest can be found on John's Blog.

Watch the video now

Related videos

PHP, by all means, is an immensely powerful language!



We may fall short of words, but there won't come any end to its qualities. The endless functionalities and possibilities of this server-side scripting language have managed to get it a strong and supportive community of PHP programmers on a global level. At present, PHP powers more than half on websites and applications on the internet.


Do you know what makes PHP so praiseworthy?



It is the simplicity, easy programming structure, and developer-friendly web functionalities that are to be credited to turn PHP into one of the top programming languages. You can create highly interactive and dynamic websites and applications with desired results by making use of PHP.



However, coding often could be a tough and tedious task to accomplish. As a solution to this, you get built-in PHP libraries that optimize the process of coding for maximum productivity.

But what are these libraries?

That's exactly what you will find out as you move ahead in this article, a list of top 12 PHP libraries capable of leading the development process in an intended manner.



So, without waiting any further, let's move ahead to learn about PHP libraries in-depth.

PChart

PChart is a PHP library assisting with the generation of text data in the form of something more appealing to the eyes and known as visual charts.



You can use this library to represent data as bar charts, pie charts, and many more different formats. The PHP script here utilizes SQL queries to put data in the impressive charts or graphs form.

Mink

Another well-known in the list of PHP libraries is Mink. It allows you to keep an eye on if a proper interaction is happening between your web apps and the browser. Eliminating the API differences between the two types of browser emulators, Mink offers an authentic testing environment for you. It also supports PHPUnit, Behat, and Symfony2.

Monolog

Monolog is a PHP logging library that helps you with saving logs to the specified locations by sending them to set files, sockets, inboxes, databases, or other web services. The use of the PSR-3 interface permits to type-hint logs in counter to your libraries that maintain optimum interoperability.

Hoa

This modular, extensible, and structured set of PHP libraries we know as Hoa establishes a link between the research and the industry.



It recommends essential paradigms, mechanisms, and algorithms for building the reliability of a site. Many PHP developers in different parts of the world use Hoa for ideal PHP development.

Guzzle

Guzzle is an HTTP client library for PHP that enables you to send HTTP requests to combine with web services.



It offers a simple interface that makes the development of query strings, POST requests, HTTP cookies, and many other attributes possible. You can also use Guzzle to send synchronous and asynchronous requests from the similar interface.

Ratchet

If your need is to develop real-time, two-directional apps between clients and servers over WebSockets, Ratchet is the PHP library you need to do it effectively.



Creating event-driven apps with Ratchet is a rapid, simple, and easy job to do!

Geocoder

Geocoder is a library to create applications that are very well geo-aware.



With Geocoder, there is an abstraction layer that helps with geocoding manipulations.



It is further split into two parts, known as HttpAdapter and Provider.

ImageWorkshop

ImageWorkshop is an open-source PHP library letting you work over the manipulation of images with layers. You can crop, resize, add watermarks, create thumbnails, and so much more. You can also enhance the images on the sites.

PhpThumb

phpThumb is the library specialized at handling the work associated with creating thumbnails with minimal coding. Accepting every image source type and image formats, it makes you do a lot ranging from rotating or cropping to watermarking or defining the image quality.

Parody

This simple library we know as Parody is used to copy classes and objects. It also provides results for method calls, acquiring properties, instantiating objects, and more. Sequential method chaining is used by Parody to produce defining class structures.

Imagine

This object-oriented PHP library is meant for working with images along with manipulating them. The often adopted operations such as resizing, cropping, and applying filters happen instantly and relatively well with Imagine.



With Imagine, you get a color class that forms the RGB values of any given color. Draw shapes like arc, ellipse, line, etc. with the features available.

PhpFastCache

PhpFastCache is an open-source PHP library that makes caching feasible. Coming as a single-file, it can be integrated within a matter of minutes.



Caching methods supported by PhpFastCache involve apc, memcache, memcached, wincache, pdo, and mpdo.


The Bottom Line




It's not about what extra difference these libraries make; it's about what significant individual contributions these libraries make for a final desired PHP app or website.



A PHP programmer, too, agrees with these libraries' benefits.



It's your time now to try and believe!

Welcome back! If you're new to this series have a look at Part 1 here

Today we are going to beef things up a bit and we will focus on the backend and some key CMS functionality.

It's time to get excited, this is where you'll start to see your barebones structure morph into something extraordinary!

Tired of my intro? That's ok! Let's jump into it!

Getting the DB on board

Before we delve into this, it's imperative that we take a minute and plan things out.

The database tables that are vital to any CMS are the menu, the user table, and the content table.

Our menu table will start of as follows:

CREATE TABLE 'mydbname'.'menus' ( 'ID' INT(11) NOT NULL AUTO_INCREMENT , 'menuname' VARCHAR(100) NOT NULL , 'item' VARCHAR(50) NOT NULL , 'itemlink' VARCHAR(100) NOT NULL , PRIMARY KEY ('ID')) ENGINE = MyISAM COMMENT = 'menu table';

Let's break this down a bit.

In the SQL above, we're creating a new table called menus.

Essentially our structure looks like this:

ID | Menuname | Item | Itemlink

Our ID field is our unique identifier (our PRIMARY KEY).

Tip: Remember, you can use raw SQL or a tool like PhpMyAdmin to create your db tables/execute SQL queries.

Next up is our user table.

CREATE TABLE 'mydbname'.'users' ( 'ID' INT(11) NOT NULL AUTO_INCREMENT , 'username' VARCHAR(100) NOT NULL , 'password' VARCHAR(50) NOT NULL , 'email' VARCHAR(100) NOT NULL , PRIMARY KEY ('ID')) ENGINE = MyISAM COMMENT = 'user table';

Visually represented this structure looks like this:

ID | Username | Password | Email

Our ID field is our unique identifier.

And finally, our content table modifications. You probably remember creating a rudimentary content table in Part 1 of the series.

ALTER TABLE 'mydbname'.'content' ADD content_type VARCHAR(50);

Yep, you guessed right, in the above statement we are altering our content table and adding a new field called content type.

Our new table structure now looks like this:

ID | Title | Content | Author | Content Type

Planning to Add to the Backend

Next , we're going to add a menu section, an add user section, and we'll also modify our content section.

Let's do this! reate a file called menus.php in your backend folder.

Next, code a HTML form to save your menu data.

The form needs the following fields:

Menu Name (we called this menuname in our db table).

Menu Item Name (we called this item in our db table).

Menu Link (we called this itemlink in our db table).

Try to follow Part 1 to do this on your own.

If you get a little stuck, that's ok. You can also follow the example below:

<form method="post" action="<?php $_SERVER['PHP_SELF'];?>"/>

<input type="text" name="menuname" class="mytextbox" placeholder="Menu Name" required />

<input type="text" name="item" class="mytextbox" placeholder="Item" required />

<input type="text" name="itemlink" class="mytextbox" placeholder="Item Link" required />

<input type="submit" value="Save Menu Item" name="savemenu" class="mybutton"/>

</form>
 

Notice the use of CSS classes? The gravy!

This will come in handy in our next tutorial.

Next, let's add the form processing code as we need to save these fields to the database. Remember to use the sanitization technique you learned in Part 2.

Add this above your <form> tag.

<?php

if(isset($_POST['savemenu'])){

include('../includes/conn.php');

if ($letsconnect->connect_error) {

die("Your Connection failed: " . $letsconnect->connect_error);

}else{

$menuname = $letsconnect ->real_escape_string($_POST['menuname']);

$item = $letsconnect -> real_escape_string($_POST['item']);

$itemlink = $letsconnect->real_escape_string($_POST['itemlink']);

$sql = "INSERT INTO menus(menuname,item,itemlink) VALUES ('".$menuname."', '".$item."', '".$itemlink."')";

if (mysqli_query($letsconnect, $sql)) {

echo "Your data was saved successfully!";

} else { echo "Error: " . $sql . "" . mysqli_error($letsconnect);

} $letsconnect->close();

}

}

?>

Ok phew, the menu data capturing section is done.

Let's move on to the user data capturing section, and modify the content capturing screen.

Repeat the steps above and create these two screens. Remember to keep an eye out for our database field names that we defined earlier! If you get stuck, look at the end result below:

Create adduser.php in your backend folder.

Create your data capturing form.

<form method="post" action="<?php $_SERVER['PHP_SELF'];?>"/>

<input type="text" name="username" class="mytextbox" placeholder="Username" required/>

<input type="password" name="password" class="mytextbox" placeholder="Password" required />

<input type="email" name="email" class="mytextbox" placeholder="Email" required />

<input type="submit" value="Save Menu Item" name="saveuser" class="mybutton"/>

</form>

Add your PHP processing code, remember the security!

Add this above your <form> tag.

<?php

if(isset($_POST[‘saveuser])){

include('../includes/conn.php');

if ($letsconnect->connect_error) {

die("Your Connection failed: " . $letsconnect->connect_error);

}else{

$menuname = $letsconnect -> real_escape_string($_POST[‘username']);

$item = $letsconnect -> real_escape_string($_POST[‘password']);

$itemlink = $letsconnect -> real_escape_string($_POST[‘email']);

$sql = "INSERT INTO menus(username,password,email) VALUES ('".$username."', '".$password."', '".$email."')";

if (mysqli_query($letsconnect, $sql)) {

echo "Your data was saved successfully!";

} else { echo "Error: " . $sql . "" . mysqli_error($letsconnect);

} $letsconnect->close();

}

}

?>

Please note that I will be covering Password security in the tutorials that follow.

Make sure that you are using your localhost server to complete this tutorial series. Do not publish your work until you complete this series.

Lastly, let's move to our content capturing screen which is currently found in index.php in the backend folder.

We will be changing this to a more professional dashboard in the tutorials that follow!
Our current file looks like this:

<html>

<head><title>Backend - Capture Content</title></head>

<body>

<?php

if(isset($_POST['savedata'])){

include('../includes/conn.php');

if ($letsconnect->connect_error) {

die("Your Connection failed: " . $letsconnect->connect_error);

}else{

$title = $letsconnect -> real_escape_string($_POST['title']);

$content = $letsconnect -> real_escape_string($_POST['content']);

$author = $letsconnect -> real_escape_string($_POST['author']);

$sql = "INSERT INTO content (title,content,author) VALUES ('".$title."', '".$content."', '".$author."')";

if (mysqli_query($letsconnect, $sql)) {

echo "Your data was saved successfully!";

} else { echo "Error: " . $sql . "" . mysqli_error($letsconnect);

} $letsconnect->close();

}

}

?>

<form action="<?php $_SERVER[‘PHP_SELF'];?>" method="post">

<input type="text" name="title" placeholder="Content Title here" required/>

<textarea name="content">Content Here</textarea>

<input type="text" name="author" placeholder="Author" required/>

<input type="submit" value="Save My Data" name="savedata"/>

</form>

</body>

</html>

We need to modify this slightly to include our new field, content_type.

Add the input field in your <form> above the submit button.

<input type="text" name="content_type" placeholder="Content Type" required/>;

Next, add the content_type to the sanitization lineup.

$content_type = $letsconnect->real_escape_string($_POST['content_type']);

Lastly, store this variable to the database by modifying the $sql.

$sql = "INSERT INTO content (title,content,author,content_type) VALUES ('".$title."', '".$content."', '".$author."', '".$content_type."')";

Conclusion

Chopping and changing is not always as daunting. Find a rhythm. There are many ways to make cumbersome coding a breeze and we will delve into that in the tutorials to come.

Challenge

Think of ways to test what we just did through retrieving and echoing data from the database.

Next Up: #CodeWithMe Part 5 Building a good base Continued

Welcome back! If you’re new to this series have a look at Part 1 here

Today’s focus is on templating, the aesthetic that will make or break your web application.

Having a clean design with well defined CSS that’s responsive and user friendly goes a long way.

Developers often stick to their lane but delving into templating will bode in your favor, you can indeed
create a functional and launch-worthy application all on your own!

Let’s jump into it!

Structured structure

Everything you tackle should be found with ease down the line. Therefore careful planning is fundamental to the success and sustainability of your project. You’ll also find that clearly defining your work lends itself to more productivity overall as you spend less that explaining your work during a handover / looking for a specific piece of code or resource. You’ll probably end up spending more time on actual work.
Finding your own unique pattern with file structure and CSS identifiers will also work in your favor as something unique to your process will most likely be easier to remember and form a tactile relationship with.

Our project’s current structure looks like this:



>If you need to backtrack, Part 1 is a great place to start!

In part 1, we created our index.php which displays info from our database.

Let’s take this a step further and create a header and a footer for our index.php

Create a file called header.php and save this to your includes folder.

Next, create a file called footer.php and save this to your includes folder.

Your file structure should now look like this.

A header above all the rest

The header file will be a file we reuse throughout your web application. This file will contain important information that’s vital to the functionality and aesthetic of your website.
The type of info you’ll expect to see in a header.php file:
Script includes
Such as JQuery and important libraries
CSS includes
CSS files loaded from internal or external sources
Meta information
Contains important information that’s readable by search engines.
The basic structure of the beginning of your app, including your menu, and your logo.
For now, how header is going to have a basic layout.

Let’s get our HTML on!

<html>
<head>
<title>My Awesome CMS – Page Title</title>
</head>
<body>

A footer that sets the bar

Create a file called footer.php and save it to your includes folder (yourcms/includes/footer.php).

Add this code to your new file.

</body>
</html>

Next, let’s focus on the gravy… The CSS

CSS, when written beautifully, can truly set you apart.

You can tell your web application to load various styles to specific elements by defining unique identifiers.
Styles that are only used once are denoted with a # (a CSS “ID”) whereas styles that are reused multiple times are denoted with a . (a CSS “class”)

The best way to delve into the realm of CSS is to learn by experience.

Let’s create!

First, we need to create and load our CSS file. Remember our nifty new pal header.php? This created a convenient way to load our CSS file!

Add the following code to your header.php just above the </head> tag.

<link href=”../assets/css/style.css” type=”text/css” rel=”stylesheet”/> 

The ../ in the link to our stylesheet means we have to leave the current directory (the directory that header.php is in) and look for the assets/css/ directories.

Go ahead and create the css folder under your assets folder.

Next we’re going to create some simple CSS to test things out.

It’s time to add some style!

We are going to create two divs.
A div is a divider / section in HTML.
Add this to your index.php (located in your CMS’ root folder) above the <?php tag.

<div id="myfirstid"></div>
<div class="myfirstclass"></div>
<div class="myfirstclass"></div>
<div class="myfirstclass"></div>
<div class="myfirstclass"></div>
<div class="myfirstclass"></div>

Then, create a CSS file

Add this:

#myfirstid{
Background:lightblue;
Font-family:Arial;
Font-size:44px; 
Font-weight: Bold; 
}
.myfirstclass{
Font-size:15px;
Color: darkblue;
}

Save your newly created CSS to assets/css/ as style.css.

Pulling it all together, let’s see what we can do!

Let’s apply what we just learned to our index.php. But first, we should add our header.php and footer.php files.

Including everyone

Add this to the top of your index.php file:

include(‘includes/header.php’);

Remove the <divs> we used for practice earlier, we have something better in store!

Add this to the bottom of your index.php:

include(‘includes/footer.php’);

Next, let’s modify our code so we can add some style to the data we retrieve from our database.

Modify the following line:

foreach($getmydata as $mydata){ echo "Title: "; echo $mydata['title']; echo "<br/>"; echo "Content: "; echo $mydata['content']; echo "<br/>"; echo "Author: "; echo $mydata['author']; echo "<br/>"; echo "<br/>";

as follows:

?>

<div id=”myfirstid”>
<?php
foreach($getmydata as $mydata){
echo "<div class=”myfirstclass”>Title: "; 
echo $mydata['title']; 
echo "<br/>"; 
echo "Content: "; 
echo $mydata['content']; 
echo "<br/>"; 
echo "Author: "; 
echo $mydata['author']; 
echo "</div><br/><br/>";
}?>
</div>
<?php 

Your full index.php should now look like this:

<?php
include('includes/header.php');
include('includes/conn.php');

if ($letsconnect -> connect_errno) { echo "Error " . $letsconnect -> connect_error;

}else{

$getmydata=$letsconnect -> query("SELECT * FROM content");

?>
<div id="myfirstid">
<?php
foreach($getmydata as $mydata){
echo "<div class=”myfirstclass”>Title: "; 
echo $mydata['title']; 
echo "<br/>"; 
echo "Content: "; 
echo $mydata['content']; 
echo "<br/>"; 
echo "Author: "; 
echo $mydata['author']; 
echo "</div><br/><br/>";
}
?>
</div>
<?php 
}

$letsconnect -> close();
include('includes/footer.php');
?>

Go ahead, test it out!

There’s a lot to unpack and I will break things down a little more during our next tutorial!

Challenge

Study the final index.php and try to form a few theories about why closing a php tag is necessary before adding raw html.

Next Up: #CodeWithMe Part 4: Building A Good Base

Welcome back!, if you’re new please be sure to read Part 1 here.

This tutorial will focus primarily on Security and will touch on how to plan functionality.

Planning out an application and seeing progress regularly is a good strategy as you are most likely to complete your tasks in a timely fashion with this approach.

Ready?, ok let’s jump into it!

DISCLAIMER

We highly recommend that you follow these tutorials on a localhost testing server like Uniserver. Read through Part 1 here to look at our recommendations. These tutorials follow a phased approach and it is highly recommended that you do not make snippets of code live prior to completing this tutorial series.

Where we left off – the serious stuff.

In the previous tutorial we saved variables to the database.

It’s important to note that further steps are needed to ensure that data transactions to / from the database are secure.

A great first step is to ensure that all POST data (data transmitted after a user clicks a form’s submit button) is sanitized.

What we’re trying to prevent

One of the most common exploits is SQL Injection, an attack most commonly used to insert SQL into db queries. POST data that’s not sanitized leaves a huge security hole for malicious exploits. In some cases SQL injection can be leveraged to rage an all out assault on a server’s operating system.

A few examples of a basic version of what this might look like can be seen below.

OUTCOME

This might delete your database table

OUTCOME

This might provide access to the entire user table and the password protected area/dashboard.


***Please note that there are various types of SQL injection techniques and I will delve into this during the course of this series.***

So what exactly is sanitization and what does it do?

When sanitizing POST data, we are essentially looking for any special characters that are often used in SQL injection attacks.

In many ways, this tiny piece of code is the unsung superhero of many database driven applications.

Let’s secure that POST data!

Navigate to your backend folder and open index.php

Locate the following line of code:

$sql = "INSERT INTO content(title,content,author)VALUES ('".$_POST["title"]."', '".$_POST["content"]."', '".$_POST["author"]."')";

Ok, let’s get to work.

Based on what I mentioned a few moments ago, it’s clear that our SQL statement is vulnerable so we need to sanitize the POST data pronto!

The method I will focus on first is $mysqli->real_escape_string. This will escape any special characters found in the POST data.

Add the following just above your $sql.

$title = $letsconnect -> real_escape_string($_POST['title']);

$content = $letsconnect -> real_escape_string($_POST['content']);

$author = $letsconnect -> real_escape_string($_POST['author']);

Did you notice the use of $letsconnect? This was used because of our db connection defined in conn.php.

Our new query will look like this:

$sql = "INSERT INTO content (title,content,author) VALUES ('".$title."', '".$content."', '".$author."')";

Go ahead and replace the old $sql.

Phew!, we can breathe easy now.

Next, let’s lighten things up a bit by focusing on functionality and aesthetics.

A phased approach is the best way to tackle projects of any size.

I tend to jot this down on paper before creating a more legible professional spec!.

Typically the phased approach lends itself to logical progression.

For example, over the next several days I will go over the following:

* Account Access
* The login process
* The registration process
* The password recovery process
* Frontend
* The look and feel
* Menus
* Sidebars
*Main Content
*Footer
* Backend
* Content Management
* Add/Edit/Delete
* Security

This will give us a good springboard to delve into more complex functionality.

The aesthetic I have in mind will be barebones at first with clean CSS practices (this will make life a whole lot easier when we have to make changes down the line!).

Challenge :

Plan out your own CMS, think about the user interface and design choices you’d like to implement, and create a phased approach.

Conclusion

I hope this tutorial encouraged you to think about security and understand one of the most common exploits. During the course of this series, you will receive the tools necessary to beef up security while maintaining your sanity!

Next up

CodeWithMe – Let’s go templating.