Developing software in the Real World

Changing an SQL Server primary key in Doctrine Migrations

I recently came across a rather weird quirk when trying to change a primary key in Sql Server using Doctrine Migrations: you need to use two migrations to get it to work. This is incredibly minor and I'm only writing it up as it confused me for a while so I thought that I'd document so that I'll find this article if I run across it again in the future! This is the migration: final… continue reading.

Testing migrating to Laminas

Zend Framework is renaming to Laminas and all the source code is moving to a new GitHub organisation. Implicitly this means a new PHP top level namespace. As you can imagine, this implies that a lot of our code will need to change, so Matthew, Michał and the team have been writing migration tooling to make this easier. It's now time to test it and they need all the help they can get on real-world… continue reading.

Embedding Notist slides

This site uses WordPress under the hood as I find the flexibility that a good CMS provides quite useful. For the talks section, I use a custom post type so that I can set additional properties on the post and customise the display. With my usual lack of imagination, my custom post type is called talk. When Notist was released, I've been uploading the PDFs for my presentations there so that I have a nicely… continue reading.

Custom error rendering in Slim 4

One of the nice things about Slim 4 is that it's easier to customise the HTML generated on error without having to worry about the rest of the error handling mechanism. This is because we have separated error rendering from error handling. Slim's default ErrorHandler maintains a list of renderers, one for each content-type and will delegate the creation of the error payload (HTML, JSON, XML, etc) to the renderer. Out of the Box, the… continue reading.

Dependency Injection in Slim 4

In contrast with Slim 2 and Slim 3, Slim 4 does not ship with a DI container, but instead, supports any PSR-11 compatibly DI container that you provide. This is part of Slim 4's commitment to interoperability via the PHP-FIG standards. The easiest way to add a container to your Slim application is to call AppFactory::setContainer() before you call AppFactory::create(). The setContainer() method expects any PSR-11 container. Register the container with Slim Let's look at… continue reading.

Running Slim 4 in a subdirectory

If you want to run Slim 4 in a subdirectory of your website, then you have a few things you need to do. Let's consider the situation: Your main website is in the directory /var/www/html and is accessed at You want your new Slim 4 app to be in the directory /var/www/html/myapp and to be accessed at Your Slim 4 index.php file is stored in /var/www/html/myapp. There are two things you need to… continue reading.

Slim4-empty: minimal Slim 4 starting point

To simplify creating a new Slim 4 project, I've created slim4-empty which does this for me. To use it: $ composer create-project akrabat/slim4-empty my-new-project and you're done! The my-new-project directory is created and contains Slim 4 along with a minimally viable public/index.php to get you going. You can then run it with the PHP built-in server: php -S -t public/ And navigate to https://localhost:8888 to view "Hello World" in your browser. What does it… continue reading.

Receiving input into a Slim 4 application

A Slim 4 (and Slim 3) application receives data from three places: Any query parameters on the URL (the key-value pairs after the ?) The HTTP message's body (usually for POST and PUT) messages Parameters in the URL (such as the 3 in Within the application, these are available within the PSR-7 Request object. Let's start with a simple Slim 4 application. Firstly we require the Slim framework and a PSR-7 implementation: $ composer… continue reading.

Displaying exif information in WordPress posts

After discovering that WordPress modifies img tags when rendering a page, it crossed my mind that I could display exif information underneath each image on my new photography blog. The basic process is applicable to any manipulation of the content that you would want to do before it is displayed. To do this, we add a new filter to the the_content hook: add_filter('the_content', function ($content) { // manipulate $content return $content; }); As with all… continue reading.

Images and WordPress

My new WordPress project has multiple photographs per post and as I wanted them to work in an efficient manner for multiple screen resolutions. The secret to this is the srcset and sizes attributes on the img tag. It turns out that WordPress will create multiple sized thumbnails when you upload an image. It will also add the srcset and sizes attributes into your img tags for you if your image tag has a class… continue reading.