PHP & Web Development Blogs

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..

    . 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!

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

Now that the Thanksgiving and Black Friday are left behind, we're all back at our desks, some of us having PHPStorm open for the whole day. In this post, I'll say a few words on this beautiful IDE, PHPUnit and XDebug.
You know that unit tests are essential, don't you? So do the PHPStorm developers. This industry-standard level IDE has tons of capabilities for integrating test frameworks and debuggers into your project. Even if you use VMs or containers to run your development environment, chances are they got you covered!



I often see even experienced PHP programmers debugging their code with var_dump(), which is obviously not the best way to do it. If you see the code for the first time, if you work with legacy code - step-by-step interactive debugging is the way to go. Sometimes it can save you hours of old school var_dumping.

As of unit tests, I often hear that it's good enough to run tests from the terminal. I even know a guy who runs watch phpunit /path/to/test while developing: this way the test is run every 2 seconds, you switch to the terminal whenever you want to see the latest results and that's it. However, there are certain advantages in running tests from the IDE. First, it's super-handy to launch a test method, test class or a whole folder with tests, just by pressing a hotkey. Second, the test results appear right there, in PHPStorm, with failures and their stack traces, every entry clickable and takes you directly to the file:line where a nasty thing happened. I also find the ability to run a debugger for a unit test, extremely attractive. Test fails, you click on a trace entry, get to a problematic line, place a break point, re-run the test in debug mode - and there you go.

For all those integrations, you will first need to setup the PHP interpreter for the project: Configuring PHP Development Environment. You will find both local and remote interpreter setups. "Local" is the PHP that you have on your workstation, the host machine. "Remote" can be pretty much everything: SSH if your Dev environment runs on a shared sandbox for all developers, docker or docker-compose if you run it using docker containers.

Next step - creating PHPUnit configuration. Go toSettings -> Languages and Frameworks -> PHP -> Test Frameworks. Follow this guide, it has much more information which will be more up-to-date than this post.Don't forget to set Path Mappings for your remote environments! That is, you probably have your project in, say, $HOME/projects/cool-project, but inside a docker or on a remote host it might be located at /app or /var/www, then you have to let PHPStorm know about this.

Once you're done with PHPUnit setup, you can finally run your tests! The default shortcut on my Linux machine isCtrl+Shift+F10 (shortcuts are usually different on Mac though). Place a cursor inside a test method, press the shotcut: PHPStorm will launch PHPUnit withthat particular test method! When the cursor in a scope of test class but not inside a test method - the whole test class will be run. And, you also can select a whole folder with tests, in the project tree and run it, ain't that cool?

A small tip for the docker-compose lovers. When I first set PHPStorm integration with docker-compose and ran the tests, I was quite surprised (unpleasantly) to see that myphp-fpm service that I was connecting to, is gone after the test process is finished. Took me some time to figure out that it's PHPStorm's expected behavior. It stops the target service after it's done testing. A workaround I started to use is as follows: I just add another service calledphpunit which uses a php-fpm or php-cli image, and is not needed by anything except unit testing in PHPStorm.

Now to debugging.

Debugging is like being the detective in a crime movie where you are also the murderer. Filipe Fortes a.k.a. @fortes

Obviously, your PHP interpreter in development environment will need a debugger extension in order for you to debug interactively. PHPStorm support the two most widely used options: XDebug and Zend Debugger. When using docker I usually make a separate Dockerfile for development, using production image as base, then add development tools,XDebug being the most important. Honestly, I've never usedZend Debugger, so have little to tell about its' nuances.

Got an extension? Go to Debugging Ultimate Guide! Debugger settings in PHPStorm are atSettings -> Languages and Frameworks -> PHP -> Debug. Most of the time you don't need to change them.Again, a note for docker-compose users. There is an XDebug setting that allow debugger to resolve the client (PHPStorm) IP address:xdebug.remoteconnect_back_. That's a disappointment but those will not work, at least with a default docker-compose setup. Thing is, all containers in a compose stack are running behind a network proxy provided by docker-compose. That is, the REMOTE_ADDR for all the containers will always be the IP of proxy. A workaround:

* disablexdebug.remoteconnect_back_;
* add.user.ini to the application root folder with the following contents:xdebug.remotehost = 192.168.X.X_ (your machine's IP address in the LAN). It's generally a good idea to exclude.user.ini from VCS control.

As a conclusion: if you still usevardump()_ to debug, stop living in the stone age, upgrade your knowledge and become more productive! If you don't write unit tests, start doing it. If your managers say it's a waste of time, tell them that it's coding without tests that is a waste of time. And, if you find this post of any use, or have an opinion, or a question - please do comment!

Hello folks! This post is for those of you using Laravel. This beautiful framework makes web development super-easy compared to most of competitors. In the heart of Laravel is the Application class, which is responsible for bootstrapping, registering services and also serves as a dependency injection container. What I do with my Laravel apps, is that I take a slight detour from the common path by adding a custom Application class. While this is not really necessary, I find this approach nice, and will try to share my thought below.

It's normal practice in Laravel world to build all kinds of objects like this:

$cache = app("cache");

I find it a bit confusing to call app("cache"") and expect a Cache\Repository instance as result. If I pass the result of this call to a function that requires a Cache\Repository as parameter, I will probably have a code inspection warning from IDE. Moreover, if I want proper autocompletion, I will have to add additional comment:

$cache = app("cache");

This is where a custom application class might be handy:

namespace App;
class MyApp extends Application
{
 public function cacheRepository(): Repository
 {
 return $this->make(Repository::class);
 }
}

This way I get a TypeError in case of a misconfiguration, and I have a type-hint which allows the IDE to recognize the return value. Bye-bye nasty comment lines and IDE warnings! I make a method per service, with type-hints, like dbConnection() or viewFactory() - works really well for me!

I also thought that, if I have a custom class, then all the custom setup that normally you have in bootstrap/app.php, should reside in that custom class:

namespace App;
class MyApp extends Application
{
 public function __construct()
 {
 define('LARAVEL_START', microtime(true));
 define("APP_ROOT", realpath(__DIR__ . "/../"));
 parent::__construct(APP_ROOT);
 $this->setUp();
 }
 private function setUp()
 {
 $this->singleton(
 Contracts\Http\Kernel::class,
 \App\Http\Kernel::class
 );
 }
}

Then your bootstrap/app.php becomes just this:

return new \App\MyApp;

The Laravel app() function will also return an instance of MyApp from now on. However, it's @phpdoc says it returns \Illuminate\Foundation\Application, so for better clarity, I also added my own accessor method:

namespace App;
class MyApp extends Application
{
 public static function app(): self
 {
 
 $ret = parent::getInstance();
 return $ret;
 }
}

I tend to limit the use of global/static functions and methods, but sometimes it can be handy, and whenever I need an instance of MyApp, I just call MyApp::app(). The IDE wil be aware of the return type due to the type-hint, so I get everything I want for clean and clear development.

With your projects in Laravel, you may or may not want to follow this particular advice, but just be aware that extending a framework built-in classes for your team's comfort, is definitely something that can make your life easier. See you around, don't forget to leave comments!

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.

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