A WordPress plugin for managing YAML frontmatter schemas in theme templates and partials.

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YAML Custom Fields allows you to define structured content schemas with an intuitive interface and ACF-like template functions. Perfect for theme developers who want flexible, schema-based content management without the complexity.
<h4>Features</h4>
<ul>
<li>Define YAML schemas for page templates and template partials</li>
<li>15+ field types including string, rich-text, images, blocks, taxonomies, data objects, and more</li>
<li>Easy-to-use admin interface for managing schemas and data</li>
<li>Three-level data hierarchy:
<ul>
<li>Per-page data for individual customization (stored in post meta)</li>
<li>Per-template global data shared across all posts using the same template</li>
<li>Site-wide global data for partials like headers and footers</li>
</ul>
</li>
<li>Per-field global/local toggle: Each field can independently use template global data or page-specific data</li>
<li>Visual dual-field interface: See both template global and page-specific values side-by-side</li>
<li>Data Objects for managing structured, reusable data (universities, companies, etc.)</li>
<li>Data Validation page for reviewing imported content</li>
<li>Consolidated Export/Import page for all data types (settings, page data, data objects)</li>
<li>Simple template functions with ACF-like syntax and auto-merge behavior</li>
<li>Administrator-only access for security</li>
<li>Clean uninstall removes all database records</li>
<li>WordPress Coding Standards compliant</li>
</ul>
<h4>Supported Field Types</h4>
<ul>
<li>String – Single-line text with min/max length</li>
<li>Text – Multi-line textarea</li>
<li>Rich Text – WordPress WYSIWYG editor</li>
<li>Code – Code editor with syntax highlighting</li>
<li>Boolean – Checkbox for true/false values</li>
<li>Number – Number input with min/max constraints</li>
<li>Date – Date picker with optional time</li>
<li>Select – Dropdown with single/multiple selection</li>
<li>Taxonomy – WordPress categories, tags, or custom taxonomies with single/multiple selection</li>
<li>Post Type – Dropdown to select registered post types (Post, Page, custom post types)</li>
<li>Data Object – Reference to structured data objects managed independently (universities, companies, team members, etc.)</li>
<li>Image – WordPress media uploader for images</li>
<li>File – WordPress media uploader for any file</li>
<li>Object – Nested group of fields</li>
<li>Block – Repeatable blocks for flexible page builders</li>
</ul>
<h4>Usage Example</h4>
In your theme template:
<pre><code><?php
$hero_title = ycf_get_field('hero_title');
$hero_image = ycf_get_image('hero_image', null, 'full');
$category = ycf_get_term('category');
$post_type = ycf_get_post_type('content_type');
$university = ycf_get_data_object('university');
$features = ycf_get_field('features');
?>

<div class="hero">
 <?php if ($hero_image): ?>
 <img src="<?php echo esc_url($hero_image['url']); ?>" alt="<?php echo esc_attr($hero_image['alt']); ?>">
 <?php endif; ?>
 <h1><?php echo esc_html($hero_title); ?></h1>
 <?php if ($category): ?>
 <?php echo esc_html($category->name); ?>
 <?php endif; ?>
 <?php if ($university): ?>
 <?php echo esc_html($university['name']); ?>
 <?php endif; ?>
</div>
</code></pre>
<h3>Developer Documentation</h3>
<h4>Template Functions</h4>
Get a single field value:
<pre><code>$value = ycf_get_field('field_name');
$value = ycf_get_field('field_name', 123); // Specific post ID
$value = ycf_get_field('logo', 'partial:header.php'); // From partial
$value = ycf_get_field('title', null, $block); // From block context
</code></pre>
Get image field with details:
<pre><code>$image = ycf_get_image('field_name', null, 'full');
$image = ycf_get_image('field_name', 123, 'thumbnail'); // Specific post ID
$image = ycf_get_image('icon', null, 'medium', $block); // From block context

// Returns: array('id', 'url', 'alt', 'title', 'caption', 'description', 'width', 'height')
</code></pre>
Get file field with details:
<pre><code>$file = ycf_get_file('field_name', null);
$file = ycf_get_file('field_name', 123); // Specific post ID
$file = ycf_get_file('document', null, $block); // From block context

// Returns: array('id', 'url', 'path', 'filename', 'filesize', 'mime_type', 'title')
</code></pre>
Get taxonomy field (term or terms):
<pre><code>$term = ycf_get_term('field_name', null);
$term = ycf_get_term('field_name', 123); // Specific post ID
$term = ycf_get_term('category', null, $block); // From block context

// Returns: WP_Term object or array of WP_Term objects (for multiple selection)
</code></pre>
Get post type field:
<pre><code>$post_type = ycf_get_post_type('field_name', null);
$post_type = ycf_get_post_type('field_name', 123); // Specific post ID
$post_type = ycf_get_post_type('content_type', null, $block); // From block context

// Returns: WP_Post_Type object or null
</code></pre>
Get data object field:
<pre><code>$university = ycf_get_data_object('field_name', null);
$university = ycf_get_data_object('field_name', 123); // Specific post ID
$university = ycf_get_data_object('university', null, $block); // From block context

// Returns: Array with data object entry fields or null
</code></pre>
Get all entries of a data object type:
<pre><code>$all_universities = ycf_get_data_objects('universities');
foreach ($all_universities as $entry_id => $university) {
 echo esc_html($university['name']);
}

// Returns: Array of all entries for the specified data object type
</code></pre>
Get all fields:
<pre><code>$fields = ycf_get_fields();
$fields = ycf_get_fields(123); // Specific post ID
$fields = ycf_get_fields('partial:footer.php'); // From partial
</code></pre>
Check if field exists:
<pre><code>if (ycf_has_field('hero_title')) {
 echo ycf_get_field('hero_title');
}
</code></pre>
Working with Block fields:
<pre><code>$blocks = ycf_get_field('features');

if (!empty($blocks)) {
 foreach ($blocks as $block) {
 // Access nested fields using context_data parameter
 $title = ycf_get_field('title', null, $block);
 $icon = ycf_get_image('icon', null, 'thumbnail', $block);
 $category = ycf_get_term('category', null, $block);

 echo '<h3>' . esc_html($title) . '</h3>';
 if ($icon) {
 echo '<img src="' . esc_url($icon['url']) . '">';
 }
 if ($category) {
 echo '' . esc_html($category->name) . '';
 }
 }
}
</code></pre>
<h4>Sample YAML Schema</h4>
<pre><code>fields:
 - name: hero_title
 label: Hero Title
 type: string
 required: true
 options:
 maxlength: 100
 - name: hero_image
 label: Hero Image
 type: image
 - name: category
 label: Category
 type: taxonomy
 options:
 taxonomy: category
 - name: tags
 label: Tags
 type: taxonomy
 multiple: true
 options:
 taxonomy: post_tag
 - name: content_type
 label: Content Type
 type: post_type
 - name: university
 label: University
 type: data_object
 options:
 object_type: universities
 - name: features
 label: Features
 type: block
 list: true
 blockKey: type
 blocks:
 - name: feature
 label: Feature Block
 fields:
 - name: title
 label: Title
 type: string
 - name: icon
 label: Icon
 type: image
 - name: description
 label: Description
 type: text
</code></pre>
<h4>Working with Partials</h4>
For custom partials, add the @ycf marker in the file header:
<pre><code><?php
/**
 * Custom Navigation Partial
 * @ycf
 */
</code></pre>
Then click “Refresh Template List” in the YAML Custom Fields admin page.
<h4>Template Global Fields</h4>
Template Global Fields allow you to define default values that are shared across all posts using the same template, while still allowing individual posts to override specific fields.
Setting up Template Global:
<ol>
<li>Go to YAML Custom Fields admin page</li>
<li>Enable YAML for your template (e.g., page.php)</li>
<li>Click Add Template Global to define the template global schema</li>
<li>Define fields that should have shared default values</li>
<li>Click Manage Template Global Data to set the default values</li>
</ol>
Using Template Global in Posts:
When editing a post that uses a template with Template Global fields, you’ll see a dual-field interface for each field:
<ul>
<li>Template Global (All Pages) – Read-only display showing the default value (with Edit link)</li>
<li>Page-Specific Value – Editable field for this post only</li>
<li>Checkbox – “Use template global for this field” – Toggle per field</li>
</ul>
Benefits:
<ul>
<li>Consistency: Set default values once, use across all posts</li>
<li>Flexibility: Override any field on any post individually</li>
<li>Clarity: See both global and local values side-by-side</li>
<li>Efficiency: Update template global to affect all posts at once</li>
</ul>
Data Priority (when using template functions):
When a field uses template global, <code>ycf_get_field()</code> returns data in this priority order:
<ol>
<li>Page-specific value (if “use template global” is unchecked)</li>
<li>Template global value (if “use template global” is checked)</li>
<li>Site-wide global value (if template has site-wide global enabled)</li>
<li>null (if no value exists)</li>
</ol>
<h4>Data Storage</h4>
<ul>
<li>Page/Post data: Stored in post meta with key <code>_yaml_cf_data</code></li>
<li>Template Global preferences: Stored in post meta with key <code>_yaml_cf_use_template_global_fields</code> (per-field array)</li>
<li>Template Global schemas: Stored in options table with key <code>yaml_cf_template_global_schemas</code></li>
<li>Template Global data: Stored in options table with key <code>yaml_cf_template_global_data</code></li>
<li>Site-wide global schema: Stored in options table with key <code>yaml_cf_global_schema</code></li>
<li>Site-wide global data: Stored in options table with key <code>yaml_cf_global_data</code></li>
<li>Partial data: Stored in options table with key <code>yaml_cf_partial_data</code></li>
<li>Schemas: Stored in options table with key <code>yaml_cf_schemas</code></li>
<li>Data Object Types: Stored in options table with key <code>yaml_cf_data_object_types</code></li>
<li>Data Object Entries: Stored in options table with keys <code>yaml_cf_data_object_entries_{type_slug}</code></li>
</ul>
<h3>Privacy Policy</h3>
YAML Custom Fields does not collect, store, or transmit any user data outside of your WordPress installation. All data is stored locally in your WordPress database.
<h3>Third-Party Libraries</h3>
This plugin includes the following third-party libraries:
<ul>
<li>Symfony YAML Component (v6.4) – Licensed under MIT License (GPL-compatible)
<ul>
<li>Homepage: https://symfony.com/components/Yaml</li>
<li>License: https://github.com/symfony/yaml/blob/7.3/LICENSE</li>
</ul>
</li>
</ul>
<h3>Credits</h3>
<ul>
<li>Author: <a href="https://www.silvestar.codes" rel="nofollow ugc">Silvestar Bistrovic</a></li>
</ul>
<h3>Support</h3>
For documentation, examples, and support, visit: 
* <a href="https://github.com/maliMirkec/yaml-custom-fields" rel="nofollow ugc">Plugin Documentation</a> 
* <a href="https://github.com/maliMirkec/yaml-custom-fields/issues" rel="nofollow ugc">Report Issues</a>

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