PHP Tag Archive

Optimize WordPress MySQL tables through Cron, behind the scenes

To regularly optimize my WordPress database tables, I created a small plugin that utilizes the WordPress Cron feature. This comes in handy to perform database optimization for WordPress on a regular basis, without forgetting about it. Just activate and enjoy. And here is the plugin code.

Cracking PHP rand()

Webapps occasionaly need to create tokens that are hard to guess. For example for session tokens or CSRF tokens, or in forgot password functionality where you get a token mailed to reset your password. These tokens should be cryptographically secure, but are often made by calling rand() multiple times and transforming the output to a string. This post will explore how hard it is to predict a token made with rand().

Generate pseudo-random passwords with OpenSSL

OpenSSL comes in handy when you need to generate random passwords, for example for system accounts and services. In this short post I’ll give you a quick example on how to generate random passwords with OpenSSL in Linux (Bash), Windows and PHP…

How to optimize PHP OPcache configuration

Tune PHP OPcache and make OPcache perform even better! After you’ve optimized realpath_cache_size, it’s time to fine-tune PHP OPcache. With just a few tweaks you can tune OPcache to make it perform much better, and here is how!

Add a delay to your WordPress login form

This plugin adds a three second delay when logging into WordPress. This slows down brute-force attacks on your website. However, it is not recommended to use sleep(), because a heavy brute-force attack will let all those POST requests sleep for the given amount of time.

Secure WordPress uploads folder, disable PHP execution

Deny direct access to PHP files in wp-content/uploads/. The following PHP function secures your WordPress website by disabling the execution of PHP scripts in wp-content/uploads, on Windows Server IIS web servers. It creates a web.config file for this purpose.

PHP 5.6 default_charset change may break HTML output

An important note for everyone who’s upgrading from PHP 5.4 and PHP 5.5 to PHP 5.6: the PHP default_charset in php.ini changed from “empty” to UTF-8, often breaking sites after upgradiong from PHP 5.4 and PHP 5.5 to PHP 5.6. UTF-8 encoding breaks when upgrading PHP 5.6 to PHP 7.0. Fix
PHP with ini_set( ‘default_charset’, “” ); or in your php.ini with default_charset = “”.

How to set a good PHP realpath_cache_size

Learn how to set a good PHP realpath_cache_size and optimize your PHP performance. . Increasing realpath_cache_size might greatly improve PHP performance, as PHP states: “this value should be increased on systems where PHP opens many files.” Setting a correct value for PHP realpath_cache_size can greatly improve PHP performance and optimize WordPress – and other CMS’s – websites.

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Redirect old URL to new URL or send 404 page with PHP

Redirect pages with PHP. If you’ve moved some old PHP pages, or URLs, to new pages and URLs, you can use the following PHP code snippet to easily redirect all visitors and incoming requests to the new location. This PHP code snippet uses a 301 Moved Permanently redirect, perfect for SEO.

Display commas in WordPress tags

Sometimes you may want to display commas in tag names. For example if you have a business directory listing and want to create one single taxonomy (tag name) “cafe, restaurant, bar”. This post shows you how to create a filter in your functions.php file to display WordPress tags with a comma, enjoy!

Check website availability with PHP and cURL

Perform a PHP cURL request to check if your website is up or not. Verify your website’s online status and availability using just PHP. This script comes in handy because website uptime and availability is important, and you want your website to be always online available. If your website is down, it’ll send you an email to notify you about downtime.