WordPress dev tip: How to move the Featured Image box up… to just below the Publish box

Whenever I’m doing development on a WordPress site that makes heavy use of taxonomies (it happens with meta data-rich portfolios for architects, for instance, which seems to be a niche for me), I get really annoyed with how much WordPress devalues the Featured Image meta box. I don’t want it shoved way down below all of the taxonomies, mainly because users will probably forget or never even know that it’s there!

What I really want is to have the Featured Image box near — but not at — the top of the sidebar. Specifically, I want it to come just below the Publish meta box.

I’ve found some resources online that almost got me there, but not quite. However a minor tweak to this example solves the problem for me.

I’m taking some shortcuts here, some of which you may not like. First, most tutorials on manipulating meta boxes encourage you to remove them and then add duplicates with a slightly different ID. I think what’s happening here though (not having inspected the source code!) is that your modifications to the add_meta_boxes action run before the standard WordPress meta boxes get loaded (possibly/probably because, as you’ll see, we’re setting the priority to high), so if you’ve created one with the same ID as a default box, yours takes precedence.

The other shortcut I’m taking, which I suspect will be more controversial (but it’s just the way I like to do this) is that I am creating an anonymous function directly within the add_action() call. That’s just a personal preference, but I like to do it because 1) it keeps the code more compact and 2) it avoids creating a bunch of named functions that have no business ever being called anywhere else anyway.

So what’s happening here? First, I’m creating the Publish meta box. Then I’m creating the Featured Image meta box. By giving them both high priority, WordPress makes them the first two meta boxes in the sidebar. The reason I have to create the Publish meta box is that, if I didn’t, Featured Image would come first, above it. I don’t want that.

I’ve set the $screen parameter to null so this will happen on all editing screens, but if you only wanted to move Featured Image up on posts and not on pages, for example, you could set it to 'post'.

Here’s the full code:

add_action('add_meta_boxes', function() {
  add_meta_box('submitdiv', __('Publish'), 'post_submit_meta_box', null, 'side', 'high');
  add_meta_box('postimagediv', __('Featured Image'), 'post_thumbnail_meta_box', null, 'side', 'high');
});

For more background, check out the official documentation on the add_meta_box() function.

Make Advanced Custom Fields smarter about handling date fields

I love Advanced Custom Fields almost as much as I love WordPress itself. But that’s not to say it doesn’t have its problems. Most are obscure, and minor… and incredibly aggravating once you stumble upon them.

Here’s one such case. Date Picker fields are great, but no one seems to be able to agree on how to store dates in a database… other than insisting on avoiding Unix timestamps, the obvious choice.

ACF stores its dates, for some reason, in YYYYMMDD format (or, as we’d express it in PHP Land, Ymd). No delimiters at all. If you’re not going to use Unix timestamps, why not at least use the MySQL convention of Y-m-d H:i:s? But I digress.

I’m presently working on a project that merges some functionality of ACF and Gravity Forms, along with some custom code, to create a jobs board. It’s super-slick how Gravity Forms can create posts from a form submission, and even set them to pending review so a site editor can come in and review them before publishing.

But… dates. Jobs boards have a lot of dates. And while Gravity Forms offers a wealth of options for date string format, Ymd isn’t one of them. So it ends up storing the date value in the database in a format ACF doesn’t like. Because ACF is very picky. It wants that format, and no other. If the value in the field is not in Ymd format, the value displayed on the admin editing screen is just… blank. And then when you save, whatever was previously saved in that field is erased.

It doesn’t have to be this way. And thanks to the following bit of code, it won’t be. Now bear in mind, this is only altering what ACF renders on the editing screen. Once you’ve saved again from that point, the date will be stored in ACF’s preferred format, but up until then, it will be in whatever other format it was in when it landed in the database.

If you’re writing your front end code proactively, that won’t matter. Because you’re already assuming data inconsistency and using strtotime() to standardize any dates you’re working with in your templates, right? Of course you are.

OK, then. So the real goal here is just to get ACF to display the correct, saved date when you go in to edit the post, so it doesn’t then wipe out the date when you hit Save Changes.

In your functions.php file, or wherever you think is best (a plugin would be nice), do this:

function acf_smart_dates($field) {
  if ($field['value']) {
    $field['value'] = date('Ymd',strtotime($field['value']));
  }
  return $field;
}
add_filter('acf/prepare_field/type=date_picker','acf_smart_dates');

That’ll do.

The simple way to add a “force SSL” option in WordPress

There are plugins for just about everything in WordPress. But cluttering up your site with plugins isn’t always such a great idea. They add bloat that can slow down your site, and if poorly written can cause potential conflicts.

Plus, a lot of them are simply over-engineered. I hate that.

That said, I love good plugins, especially Advanced Custom Fields by Elliot Condon. I consider it essential to every WordPress site I build… which is a lot these days.

A site I’m currently working on has some pages that require SSL encryption. And I want the client to be able to turn SSL on or off on a per-page basis. But I didn’t want to use a plugin (besides ACF) to do it. [Disclaimer: you don’t actually need to use ACF for this; the standard Custom Fields capability will do.]

Before getting started, make sure your site actually has an SSL certificate installed and properly configured. And for this to work as shown, the cert needs to use the same domain name as the site itself. If it’s different, your redirect URLs will be a bit more complicated and will require some customization of this code, but it’ll still work.

First, set up your custom field. I’m using force_https as the field name, but it can be whatever. Make it a True/False field. (If you’re not using ACF, just remember you’ll be entering 0 or 1 as the value.)

Next, in your functions.php file, add the following:

add_action('template_redirect', 'my_force_https');
function my_force_https() {
  if (is_ssl()) { return null; }
  global $post;
  if (!empty($post->ID)) {
    if (!empty(get_field('force_https',$post->ID))) {
      $ssl_url = str_replace('http://','https://',get_the_permalink($post->ID));
      wp_redirect($ssl_url); exit;
    }
  }
  return false;
}

Picking this apart: We’re using the template_redirect hook. By this point the post has been loaded. We have all of the data we need, and it’s kind of our “last chance” to get WordPress to do a redirect before it starts rendering the page.

First we run the built-in WordPress function is_ssl(), because if we’re already on an SSL connection, there’s nothing to do. (And, if we didn’t do this check, we’d create a redirect loop.)

Next, if we have a post ID, we use the ACF function get_field() to check whether the force_https custom field is checked for this page. If it is, then we modify the page’s permalink to start with https:// and trigger the redirect. That’s it! [Note: If you’re not using ACF, you’ll need to use the built-in WordPress function get_post_meta() instead of get_field().]

Of course, that’s not quite it. You may notice after you have this working that your page loads with an https:// URL, but you’re still not getting the reassuring lock icon in your browser’s address bar. What gives?

Well, that’s because you probably have assets in the page that are loading over a non-SSL connection. In my experience, this is almost always because of images in your content that have a full, non-SSL URL. Browsers won’t give you the lock icon unless every asset on the page was loaded over an SSL connection.

So I’ve added this second function that strips the protocol from any instance of src="http://... in a text string. If you’re not familiar with “protocol-less” URLs, modern browsers allow you to omit the protocol — http:// or https:// — from URLs in your HTML, using just // instead, and the browser will automatically handle those with the same protocol used to load the page.

Using the filter the_content, this will automatically get applied to most page content and you’ll probably be good.

add_filter('the_content', 'my_strip_protocol');
function my_strip_protocol($content) {
  if (is_ssl()) {
    $content = str_replace('src="http://','src="//',$content);
  }
  return $content;
}

If you add this and you’re still not getting the lock, it means you probably have <img> tags within your theme that include full non-SSL URLs, or possibly some CSS or JavaScript assets that are being loaded over non-SSL connections. You’ll have to troubleshoot that yourself, but with the developer tools built into modern web browsers, that shouldn’t be too difficult. Remember, now that you have it, you can always use this my_strip_protocol() function directly in your theme files as well.

Just a side note about one of my idiosyncratic coding conventions: I always use !empty() when checking for a value that evaluates to true, but you don’t have to. It comes from my prior experience working with CakePHP. The benefit is that you won’t trigger any PHP warnings if the variable you’re evaluating hasn’t been declared.

WordPress challenge of the day: sorting by meta value, including posts WITHOUT that meta value set

I dug around quite a bit for a solution to this today, and eventually I found one, even though it’s a bit ugly.

The problem here is in setting up a WordPress query that sorts posts based on a meta value. I wanted to sort a list of pages by template, but I wanted to include all of the pages, even ones that don’t explicitly have a template set. But the default query was only showing the ones that did have the template value.

Several dead ends almost led me to give up, until I realized it was a JOIN issue. Specifically, the need to change an INNER JOIN to a LEFT JOIN. I just needed to figure out how to do that in the context of WP_Query.

Cut to the chase, here’s what I ended up with.

add_action('pre_get_posts', function($query) {
  if (!is_admin()) { return; }
  $orderby = $query->get('orderby');
  if ('_wp_page_template' == $orderby) {
    $query->set('meta_key','_wp_page_template');
    $query->set('orderby','meta_value');
    // Workaround to include items without this meta key
    // Based on: https://core.trac.wordpress.org/ticket/19653#comment:11
    add_filter('get_meta_sql', function($clauses) {
      $clauses['join'] = str_replace('INNER JOIN','LEFT JOIN',$clauses['join']) . $clauses['where'];
      $clauses['where'] = '';
      return $clauses;
    });
  }
});

I don’t like doing a str_replace() on part of the pre-built query, but sometimes you gotta do what you gotta do. Also note that this is part of a larger function I am writing that is only for use in the admin side; you could remove that is_admin() check if you want this to work everywhere.

I haven’t had a chance to dig into the details of the query to figure out why the original source post included moving $clauses['where'] into $clauses['join'], but it’s essential. I tried skipping it, and it didn’t work.

Sorry I can’t provide any more context here… but I hope it’s helpful to anyone who finds themselves in a similar situation!

How to REALLY check if the content is empty in WordPress

Problem: You want to check if the content in a WordPress post is empty. Seems easy, but do a Google search on the topic and you’ll see the question asked and — incorrectly — answered several times.

The fact is, I know how to do this. I was just hoping there was a built-in function in WordPress that I didn’t know about. Apparently not, so I wrote my own.

Why isn’t it easy and obvious how to check for the content being empty? Well, you could do this:

if ($post->post_content == '') { ... }

That will work. If the content is really empty. That means a zero-length string. As in strlen($post->post_content) == 0. Which it might be. But probably not.

If you’ve worked with real world site content, or even someone else’s Word documents before, you know that blank space is invisible, and a lot of times there’s a lot of blank space in a document that is not truly “empty.” Spaces, line breaks, HTML paragraphs with nothing but a non-breaking space in them. It all takes up space, and makes the content look empty, even when it’s not.

That last example is the critical one here. A WordPress post may look like it has no content, but if someone pressed Enter while the cursor was in the content box and then saved the page, it most likely has at least one <p>&nbsp;</p> in it.

So what you need is a function that takes all of that invisible cruft into account. Since it doesn’t seem like WordPress has such a function built in, I wrote my own, which I have made as compact as possible:

function empty_content($str) {
    return trim(str_replace('&nbsp;','',strip_tags($str))) == '';
}

This function takes the string you pass into it, strips out all HTML tags, then removes any non-breaking space entities, and then trims all whitespace. If there’s nothing but that stuff, then it becomes an empty string. If there’s any “real” content, the string won’t be empty. Then it just compares whatever it has left against an actual empty string, and returns the boolean result.

So now if you want to check if the WordPress content is really empty, you can do this:

if (empty_content($post->post_content)) { ... }

This will return true if the content is empty; false if it’s not.

Update (8/31/2017): This post continues to be one of the most frequently viewed on my blog, and I’ve been meaning for ages to amend it with this important note. As written here, you’ll get an erroneous true returned if the only content is in HTML, for instance, an image. If you want the function to return false if there’s no text content, then leave it as-is. But you can add a second input parameter to the strip_tags() function to tell it to leave certain HTML tags alone. If you want to allow image tags, for instance, the modified code would read as such:

function empty_content($str) {
    return trim(str_replace('&nbsp;','',strip_tags($str,'<img>'))) == '';
}