WP_REST_URL_Details_Controller::get_meta_with_content_elements( string $html ): array
- Since
- 5.9.0
- Source
wp-includes/rest-api/endpoints/class-wp-rest-url-details-controller.php:535
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
$htmlstring- The string of HTML to be parsed.
Return value
array- A multidimensional 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.
Performance profile
How much work a call to WP_REST_URL_Details_Controller::get_meta_with_content_elements() 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
- Scaling
- Constant
- Instructions
- 7
- Plugin surface
- None
- Called by
- 1
Touches nothing outside its own arguments.
No loop in the body: the same number of instructions runs whatever you pass in.
Executed per call on PHP 8.5. The body compiles to 7.
Nothing here hands control to plugin code.
1 place in core call this, so the cost is paid more often than your own code shows.
What it touches
- regexregular expression over the whole input
preg_match_all()called directly
What one call costs · 1 distinct outcome
One number would be a lie: the work depends on which branch runs. These are every distinct cost WP_REST_URL_Details_Controller::get_meta_with_content_elements() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
| always | 7 | preg_match_all() |
Across PHP versions
Compiles the same on PHP 7.4, 8.1, 8.2, 8.3, 8.4, 8.5 and 8.6-dev: 7 instructions, 7 executed per call, 0 branches. The work does not change between versions.
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 · 1
- WP_REST_URL_Details_Controller::parse_url_details()Retrieves the contents of the title tag from the HTML response.
Source code
private function get_meta_with_content_elements( $html ) { /* * Parse all meta elements with a content attribute. * * Why first search for the content attribute rather than directly searching for name=description element? * tl;dr The content attribute's value will be truncated when it contains a > symbol. * * The content attribute's value (i.e. the description to get) can have HTML in it and be well-formed as * it's a string to the browser. Imagine what happens when attempting to match for the name=description * first. Hmm, if a > or /> symbol is in the content attribute's value, then it terminates the match * as the element's closing symbol. But wait, it's in the content attribute and is not the end of the * element. This is a limitation of using regex. It can't determine "wait a minute this is inside of quotation". * If this happens, what gets matched is not the entire element or all of the content. * * Why not search for the name=description and then content="(.*)"? * The attribute order could be opposite. Plus, additional attributes may exist including being between * the name and content attributes. * * Why not lookahead? * Lookahead is not constrained to stay within the element. The first <meta it finds may not include * the name or content, but rather could be from a different element downstream. */ $pattern = '#<meta\s' . /* * Allows for additional attributes before the content attribute. * Searches for anything other than > symbol. */ '[^>]*' . /* * Find the content attribute. When found, capture its value (.*). * * Allows for (a) single or 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. */ 'content=(["\']??)(.*)\1' . /* * Allows for additional attributes after the content attribute. * Searches for anything other than > symbol. */ '[^>]*' . /* * \/?> searches for the closing > symbol, which can be in either /> or > format. * # ends the pattern. */ '\/?>#' . /* * These are the options: * - i : case-insensitive * - s : allows newline characters for the . match (needed for multiline elements) * - U means non-greedy matching */ 'isU'; preg_match_all( $pattern, $html, $elements ); return $elements; }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.