WP’s Backbone-like Templating Language

In yesterday’s post, I talked about fixing up old PHP code to be safer.

There’s another anti-pattern common in old PHP code, and that’s mixing the display logic with the output logic. While some of this is inevitable, nowadays, the rule is to use a templating system like Twig to separate out even small bits of HTML code from the logic.

WordPress does this on the front end via Underscore templates, but configured to use Handlebars-like syntax.

This is a PHP class that does the same thing with PHP. I wrote it so I could use the same, or similar, templates on both the client and server side.
Continue reading WP’s Backbone-like Templating Language

WordPress Customizer, Selective Refresh and Partials for Multiple Settings

There are several good references about how to set up the Customizer to avoid refreshing the entire page with each change. There’s one here, and there’s some deeper explanation here. What’s not described much is how to map several settings to a single area of the page (called a Partial).

This tutorial will go into updating Partials that use several settings. I assume you have already done the other tutorials.
Continue reading WordPress Customizer, Selective Refresh and Partials for Multiple Settings

WordPress Plugin Update and Install Functions

On the page where they explain how to create tables for your plugin, there’s a link to the register_activation_hook function, which is run when the plugin is activated. However, right in the first section, it says:

Note: Don’t use activation hooks (especially for multisite). Do this instead:

It’s far better to use an upgrade routine fired on admin_init, and handle that per-site, basing it on a stored option.

That links to another page, which repeats the information, but doesn’t tell you how to do this. Here’s one way. Continue reading WordPress Plugin Update and Install Functions

filter_var? filter_input? No, Use Filter Input Array to Modernize Legacy Code (Best Practices)

I’ve been a real nut for filter_var() for years, and have come up with concise ways to use it, but totally missed this other function, which, at first look, seemed a little too specialized.

filter_input_array()

Well, I was so wrong. This is a great way to filter inputs. I figured this out when I had to fix up some code because it was throwing a zillion “Notice, index foobar not defined.” in the error logs. Continue reading filter_var? filter_input? No, Use Filter Input Array to Modernize Legacy Code (Best Practices)

Developing admin-ajax.php Handlers with PHPUnit and Curl (WordPress WP)

The typical way I’ve made AJAX handlers that hook into admin-ajax.php is with Firebug and little bits of Javascript code to exercise the REST API. The problem with this is that you lose all the development code. This note shows how to use PHPUnit to write your code as tests, and develop the REST API using something like test driven development (TDD). Continue reading Developing admin-ajax.php Handlers with PHPUnit and Curl (WordPress WP)