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 1080 (+20 into the body)

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

2. 2
   apply_filters( wp_kses_allowed_html )filterline 1086 (+26 into the body)

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

3. 3
   apply_filters( wp_kses_allowed_html )filterline 1103 (+43 into the body)

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

4. 4
   apply_filters( wp_kses_allowed_html )filterline 1115 (+55 into the body)

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

5. 5
   apply_filters( wp_kses_allowed_html )filterline 1119 (+59 into the body)

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

6. 6
   apply_filters( wp_kses_allowed_html )filterline 1123 (+63 into the body)

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

7. 7
   apply_filters( wp_kses_allowed_html )filterline 1128 (+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 ↗

1060function wp_kses_allowed_html( $context = '' ) {1061	global $allowedposttags, $allowedtags, $allowedentitynames;1062 1063	if ( is_array( $context ) ) {1064		// When `$context` is an array it's actually an array of allowed HTML elements and attributes.1065		$html    = $context;1066		$context = 'explicit';1067 1068		/**1069		 * Filters the HTML tags that are allowed for a given context.1070		 *1071		 * HTML tags and attribute names are case-insensitive in HTML but must be1072		 * added to the KSES allow list in lowercase. An item added to the allow list1073		 * in upper or mixed case will not recognized as permitted by KSES.1074		 *1075		 * @since 3.5.01076		 *1077		 * @param array[] $html    Allowed HTML tags.1078		 * @param string  $context Context name.1079		 */1080		return apply_filters( 'wp_kses_allowed_html', $html, $context );1081	}1082 1083	switch ( $context ) {1084		case 'post':1085			/** This filter is documented in wp-includes/kses.php */1086			$tags = apply_filters( 'wp_kses_allowed_html', $allowedposttags, $context );1087 1088			// 5.0.1 removed the `<form>` tag, allow it if a filter is allowing it's sub-elements `<input>` or `<select>`.1089			if ( ! CUSTOM_TAGS && ! isset( $tags['form'] ) && ( isset( $tags['input'] ) || isset( $tags['select'] ) ) ) {1090				$tags = $allowedposttags;1091 1092				$tags['form'] = array(1093					'action'         => true,1094					'accept'         => true,1095					'accept-charset' => true,1096					'enctype'        => true,1097					'method'         => true,1098					'name'           => true,1099					'target'         => true,1100				);1101 1102				/** This filter is documented in wp-includes/kses.php */1103				$tags = apply_filters( 'wp_kses_allowed_html', $tags, $context );1104			}1105 1106			return $tags;1107 1108		case 'user_description':1109		case 'pre_term_description':1110		case 'pre_user_description':1111			$tags                = $allowedtags;1112			$tags['a']['rel']    = true;1113			$tags['a']['target'] = true;1114			/** This filter is documented in wp-includes/kses.php */1115			return apply_filters( 'wp_kses_allowed_html', $tags, $context );1116 1117		case 'strip':1118			/** This filter is documented in wp-includes/kses.php */1119			return apply_filters( 'wp_kses_allowed_html', array(), $context );1120 1121		case 'entities':1122			/** This filter is documented in wp-includes/kses.php */1123			return apply_filters( 'wp_kses_allowed_html', $allowedentitynames, $context );1124 1125		case 'data':1126		default:1127			/** This filter is documented in wp-includes/kses.php */1128			return apply_filters( 'wp_kses_allowed_html', $allowedtags, $context );1129	}1130}

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 6.9.7 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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