WordPress Plugin : Image Processing Queue

As described in “Introducing WP Image Processing Queue – On‑the‑Fly Image Processing Done Right“, Image Processing Queue plugin tries to solve several issues with On-The-Fly Image Processing (OTFIP) in WordPress.  Some of the things that it improves are:

  • Response times for pages with non-yet generated thumbnails.
  • Server CPU spikes for pages which use a lot of images on sites with a lot of configured thumbnail sizes (49? really? WOW! I don’t think I’ve seen more than 10 in the wild, which is still a lot).
  • Server disk space issues caused by removed images and leftover thumbnails.

This is a very useful direction and I hope all the necessary bits will make it into the WordPress core.  But even for those who don’t use WordPress, the whole discussion and implementation are a handy reference.

PHPUnit Snapshot Assertions – a way to test without writing actual test cases

phpunit-snapshot-assertions – is an interesting addition to the PHPUnit assertions which allows testing against previously created snapshots.  This is particularly useful for testing the outputs of API end-points, format conversion functions, and the like.  Instead of testing the actual functionality, these assertions allow to compare the output of the current test run with the known good output of a previously created snapshot.

This works well for generic text, but even better for widely used formats like JSON and XML, where, in case of a failed assertion, a meaningful difference can be provided.

Here is a blog post providing some more details on philosophy and methodology.

Charles – web debugging proxy application

Charles is a web debugging proxy application for Windows, Mac OS, and Linux.  Here’s a quick description from the project’s website:

Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine and the Internet. This includes requests, responses and the HTTP headers (which contain the cookies and caching information).

And here are some key features:

  • SSL Proxying – view SSL requests and responses in plain text
  • Bandwidth Throttling to simulate slower Internet connections including latency
  • AJAX debugging – view XML and JSON requests and responses as a tree or as text
  • AMF – view the contents of Flash Remoting / Flex Remoting messages as a tree
  • Repeat requests to test back-end changes
  • Edit requests to test different inputs
  • Breakpoints to intercept and edit requests or responses
  • Validate recorded HTML, CSS and RSS/atom responses using the W3C validator

Pretty much every browser these days comes with developer tools (like Google Chrome, for example).

But these are mostly useful for requests made by the browser itself.  Often, like depicted in “PHP and cURL: How WordPress makes HTTP requests” blog post from which I learned about Charles, one needs to examine requests made by the application itself – like WordPress in this particular case.

The developer tools of the browser won’t be very useful, but a proxy application like Charles would.  Setting up a proxy will send all requests through it, allowing for easy inspection and debugging.

How to Synchronize WordPress Live and Development Databases

SitePoint runs through a few options that one can use to synchronize WordPress live and development databases.  I’ve linked to  some of these options before, but it’s nice to have them all conveniently together.  The solutions discussed include WordPress-specific tools:

as well as generic tools, such mysqldump, mysqlpump, rsync, and git.

Overall, it’s a pretty complete list of tools.  The one I’d like to add though is WP CLI, which allows a great deal of automation when it comes to WordPress, including things like database imports and exports, post and option management, and more.


Dependency Management and WordPress: A Proposal

I came across this article – “Dependency Management and WordPress: A Proposal“, which provides an excellent overview of some of the recent developments and discussions in the area of composer integration with WordPress, and even more generically, some of the issues around dependency management in an ecosystem as large and complex as that of WordPress.

It’s been a while since I checked what’s going on in this area.  A couple of years back, I linked to an article that shows a way to use composer with WordPress, and since then I’ve built something similar for our use at work.

But it’s good to see that the problem is not tossed and forgotten, and that there are some very smart people still trying to work it out.

Payum – PHP 5.5+ payment processing library

Payum – PHP 5.5+ payment processing library, which is self-described as:

It offers everything you need to work with payments: Credit card & offsite purchasing, subscriptions, payouts etc.

The documentation looks extensive, and the list of supported gateways is probably the longest I’ve seen.

Creating Strictly Typed Arrays and Collections in PHP

This SitePoint PHP blog post (read at Planet PHP if the site is unavailable) brings to light a very useful feature available since PHP 5.6 – ellipses in functional arguments, which allows to define a variable number of arguments to a function.

I’ve seen the mentions of ellipses a few times now, but I assumed that it was a PHP 7 feature.  Turns out PHP 5.6 users can enjoy it as well:

function sum(...$numbers) {
    $acc = 0;
    foreach ($numbers as $n) {
        $acc += $n; 
    return $acc;
echo sum(1, 2, 3, 4); // prints out 10

This is very useful, but, as SitePoint PHP blog most mentions, it can be made even more useful with type hinting of the arguments.  For example:

class Movie { private $dates = [];
    public function setAirDates(\DateTimeImmutable ...$dates) { 
        $this->dates = $dates;

    public function getAirDates() {
        return $this->dates;

The limitation is that you can only hint a single type for all the arguments. The workaround this is to use collection classes, which basically work as strictly typed arrays.

PHPQA all-in-one Analyzer CLI tool

PHPQA all-in-one Analyzer CLI tool.  This project bundles together all the usual PHP quality control tools, and then some.  It simplifies the installation and configuration of the tools and helps developers to push up the quality control bar on their projects.

The tools currently included are:

php-enqueue – enterprise queue solutions for PHP

php-enqueue – enterprise queue solutions for PHP.  There is a number of GitHub repositories for the project.  PHP Enqueue supports a number of transports – ampq, stomp, filesystem – and it provides a flexible collection of classes to deal both with the queue manager, as well as a client.  If your project needs a message queue, definitely check this one out.

Getting started with workflows in PHP

For a large project at work, we need to integrate or develop a workflow engine.  I worked a little bit with workflow engines in the past, but the subject is way to big and complex for me to claim any expertise in it.

So, I am looking at what’s available these days and what are our options.  This post is a collection of initial links and thoughts, and it’s goal is mostly to document my research process and findings, and not to provide any answers or solutions yet.

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