WP_REST_URL_Details_Controller::get_metadata_from_meta_element( array $meta_elements, string $attr, string $attr_value ): string
- Since
- 5.9.0
- Source
wp-includes/rest-api/endpoints/class-wp-rest-url-details-controller.php:618
Compatibility
- WordPress
- since 5.9.0
- PHP
- 7.4–8.6-dev
- 6.7.7
- 6.8.8
- 6.9.7
- 7.0.4
- 7.1.0
Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.
Parameters
$meta_elementsarray- A multi-dimensional indexed array on success, else empty array.
$0string[]Meta elements with a content attribute.$1string[]Content attribute's opening quotation mark.$2string[]Content attribute's value for each meta element.
$attrstring- Attribute that identifies the element with the target metadata.
$attr_valuestring- The attribute's value that identifies the element with the target metadata.
Return value
string- The metadata on success. Empty string if not found.
Performance profile
How much work a call to WP_REST_URL_Details_Controller::get_metadata_from_meta_element() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.
- Cost class
- Light
- Scaling
- Scales with input
- Instructions
- 6–34
- Plugin surface
- None
- Called by
- 2
Touches nothing outside its own arguments.
The body loops, so the work grows with what you pass in.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 35.
Nothing here hands control to plugin code.
2 places in core call this, so the cost is paid more often than your own code shows.
What one call costs · 2 distinct outcomes
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_REST_URL_Details_Controller::get_metadata_from_meta_element() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 6–15 | none |
!empty($meta_elements) && !$meta_elements && !empty($match) | 26–34 | preg_match() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 35 | 6–34 | 6 | |
| 8.5 | 35 | 6–34 | 6 | |
| 8.4 | 35 | 6–34 | 6 | 2 fewer instructions than PHP 8.3 |
| 8.3 | 37 | 6–36 | 6 | |
| 8.2 | 37 | 6–36 | 6 | |
| 8.1 | 37 | 6–36 | 6 | |
| 7.4 | 37 | 6–36 | 6 |
An instruction is not a fixed amount of time, so a matching count is not necessarily the same speed; what it rules out is a difference in the work itself.
Used by · 2
- WP_REST_URL_Details_Controller::get_description()Parses the meta description from the provided HTML.
- WP_REST_URL_Details_Controller::get_image()Parses the Open Graph (OG) Image from the provided HTML.
Source code
private function get_metadata_from_meta_element( $meta_elements, $attr, $attr_value ) { // Bail out if there are no meta elements. if ( empty( $meta_elements[0] ) ) { return ''; } $metadata = ''; $pattern = '#' . /* * Target this attribute and value to find the metadata element. * * Allows for (a) no, single, double quotes and (b) whitespace in the value. * * Why capture the opening quotation mark, i.e. (["\']), and then backreference, * i.e \1, for the closing quotation mark? * To ensure the closing quotation mark matches the opening one. Why? Attribute values * can contain quotation marks, such as an apostrophe in the content. */ $attr . '=([\"\']??)\s*' . $attr_value . '\s*\1' . /* * These are the options: * - i : case-insensitive * - s : allows newline characters for the . match (needed for multiline elements) * - U means non-greedy matching */ '#isU'; // Find the metadata element. foreach ( $meta_elements[0] as $index => $element ) { preg_match( $pattern, $element, $match ); // This is not the metadata element. Skip it. if ( empty( $match ) ) { continue; } /* * Found the metadata element. * Get the metadata from its matching content array. */ if ( isset( $meta_elements[2][ $index ] ) && is_string( $meta_elements[2][ $index ] ) ) { $metadata = trim( $meta_elements[2][ $index ] ); } break; } return $metadata; }Changelog
Introduced in 5.9.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
About this page
- Parsed data
- Generated from the wordpress-develop 7.0.4 tag, from
src/wp-includes/rest-api/endpoints/class-wp-rest-url-details-controller.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it. - Corrections
- Something wrong on this page? Report it and it gets fixed in the next regeneration.