wp_kses_allowed_html( string|array $context = '' ): array

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$contextstring|arrayoptional

The context for which to retrieve tags. Allowed values are 'post', 'strip', 'data', 'entities', or the name of a field filter such as 'pre_user_description', or an array of allowed HTML elements and attributes.Default: ''

Return value

array

Array of allowed HTML tags and their allowed attributes.

Performance profile

How much work a call to wp_kses_allowed_html() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Trivial

Touches nothing outside its own arguments.

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

13–33

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 84.

Plugin surface

1 hook

Third-party callbacks on 'wp_kses_allowed_html' run inside this call, and their cost is not bounded by anything here.

Called by

7

7 places in core call this, so the cost is paid more often than your own code shows.

What it touches

• hookthird-party callbacksapply_filters()called directly

What one call costs · 2 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_kses_allowed_html() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 7

7 hooks fire while wp_kses_allowed_html() runs, in this order:

1. 1
   apply_filters( wp_kses_allowed_html )filterline 1083 (+20 into the body)

   Filters the HTML tags that are allowed for a given context.

2. 2
   apply_filters( wp_kses_allowed_html )filterline 1089 (+26 into the body)

   Filters the HTML tags that are allowed for a given context.

3. 3
   apply_filters( wp_kses_allowed_html )filterline 1106 (+43 into the body)

   Filters the HTML tags that are allowed for a given context.

4. 4
   apply_filters( wp_kses_allowed_html )filterline 1118 (+55 into the body)

   Filters the HTML tags that are allowed for a given context.

5. 5
   apply_filters( wp_kses_allowed_html )filterline 1122 (+59 into the body)

   Filters the HTML tags that are allowed for a given context.

6. 6
   apply_filters( wp_kses_allowed_html )filterline 1126 (+63 into the body)

   Filters the HTML tags that are allowed for a given context.

7. 7
   apply_filters( wp_kses_allowed_html )filterline 1131 (+68 into the body)

   Filters the HTML tags that are allowed for a given context.

Uses · 1

• apply_filters()Calls the callback functions that have been added to a filter hook.

Used by · 7

• WP_Widget_Custom_HTML::render_control_template_scripts()Render form template scripts.
• filter_block_core_template_part_attributes()Sanitizes the value of the Template Part block's `tagName` attribute.
• gallery_shortcode()Builds the Gallery shortcode output.
• wp_get_code_editor_settings()Generates and returns code editor settings.
• wp_kses_attr()Removes all attributes, if none are allowed for this element.
• wp_kses_one_attr()Filters one HTML attribute and ensures its value is allowed.
• wp_kses_split2()Callback for `wp_kses_split()` for fixing malformed HTML tags.

Source code

View on Trac ↗View on GitHub ↗

1063function wp_kses_allowed_html( $context = '' ) {1064	global $allowedposttags, $allowedtags, $allowedentitynames;1065 1066	if ( is_array( $context ) ) {1067		// When `$context` is an array it's actually an array of allowed HTML elements and attributes.1068		$html    = $context;1069		$context = 'explicit';1070 1071		/**1072		 * Filters the HTML tags that are allowed for a given context.1073		 *1074		 * HTML tags and attribute names are case-insensitive in HTML but must be1075		 * added to the KSES allow list in lowercase. An item added to the allow list1076		 * in upper or mixed case will not recognized as permitted by KSES.1077		 *1078		 * @since 3.5.01079		 *1080		 * @param array[] $html    Allowed HTML tags.1081		 * @param string  $context Context name.1082		 */1083		return apply_filters( 'wp_kses_allowed_html', $html, $context );1084	}1085 1086	switch ( $context ) {1087		case 'post':1088			/** This filter is documented in wp-includes/kses.php */1089			$tags = apply_filters( 'wp_kses_allowed_html', $allowedposttags, $context );1090 1091			// 5.0.1 removed the `<form>` tag, allow it if a filter is allowing it's sub-elements `<input>` or `<select>`.1092			if ( ! CUSTOM_TAGS && ! isset( $tags['form'] ) && ( isset( $tags['input'] ) || isset( $tags['select'] ) ) ) {1093				$tags = $allowedposttags;1094 1095				$tags['form'] = array(1096					'action'         => true,1097					'accept'         => true,1098					'accept-charset' => true,1099					'enctype'        => true,1100					'method'         => true,1101					'name'           => true,1102					'target'         => true,1103				);1104 1105				/** This filter is documented in wp-includes/kses.php */1106				$tags = apply_filters( 'wp_kses_allowed_html', $tags, $context );1107			}1108 1109			return $tags;1110 1111		case 'user_description':1112		case 'pre_term_description':1113		case 'pre_user_description':1114			$tags                = $allowedtags;1115			$tags['a']['rel']    = true;1116			$tags['a']['target'] = true;1117			/** This filter is documented in wp-includes/kses.php */1118			return apply_filters( 'wp_kses_allowed_html', $tags, $context );1119 1120		case 'strip':1121			/** This filter is documented in wp-includes/kses.php */1122			return apply_filters( 'wp_kses_allowed_html', array(), $context );1123 1124		case 'entities':1125			/** This filter is documented in wp-includes/kses.php */1126			return apply_filters( 'wp_kses_allowed_html', $allowedentitynames, $context );1127 1128		case 'data':1129		default:1130			/** This filter is documented in wp-includes/kses.php */1131			return apply_filters( 'wp_kses_allowed_html', $allowedtags, $context );1132	}1133}

Changelog

Introduced in 3.5.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/kses.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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