atom_enclosure()
- Since
- 2.2.0
- Source
wp-includes/feed.php:519
Description
Uses the global $post to check whether the post requires a password and if the user has the password for the post. If not then it will return before displaying.
Also uses the function get_post_custom() to get the post's 'enclosure' metadata field and parses the value to display the enclosure(s). The enclosure(s) consist of link HTML tag(s) with a URI and other attributes.
Compatibility
- WordPress
- since 2.2.0
- 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.
Performance profile
How much work a call to atom_enclosure() 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
- Heavy
- Scaling
- Scales with input
- Instructions
- 4–10
- Plugin surface
- 1 hook
- Called by
- 0
Reaches the database via get_post().
The body loops, so the work grows with how much data it finds.
Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 83.
Third-party callbacks on 'atom_enclosure' run inside this call, and their cost is not bounded by anything here.
Nothing in core calls this; the cost is only what you spend yourself.
What it touches
- hookthird-party callbacks
apply_filters()called directly - querycontent query
get_post()one call below atom_enclosure()
Further down the call graph this can also reach option, cache, serialize and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.
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 atom_enclosure() can have, taken from its control-flow graph on PHP 8.5.
| When | Instructions | Calls it makes |
|---|---|---|
post_password_required() | 4 | post_password_required() |
!post_password_required() | 9–10 | post_password_required(), get_post_custom() |
Across PHP versions
| PHP | Compiled | Executed | Branches | Notes |
|---|---|---|---|---|
| 8.6-dev | 83 | 4–10 | 12 | |
| 8.5 | 83 | 4–10 | 12 | |
| 8.4 | 83 | 4–10 | 12 | 9 fewer instructions than PHP 8.3 |
| 8.3 | 92 | 4–10 | 12 | |
| 8.2 | 92 | 4–10 | 12 | |
| 8.1 | 92 | 4–10 | 12 | |
| 7.4 | 92 | 4–10 | 12 |
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.
Hooks and filters fired · 1
One hook fires while atom_enclosure() runs, in this order:
- apply_filters( atom_enclosure )filterline 565 (+46 into the body)
Filters the atom enclosure HTML link tag for the current post.
Uses · 6
- post_password_required()Determines whether the post requires password and whether a correct password has been provided.
- get_post_custom()Retrieves post meta fields, based on post ID.
- get_allowed_mime_types()Retrieves the list of allowed mime types and file extensions.
- esc_url()Checks and cleans a URL.
- esc_attr()Escaping for HTML attributes.
- apply_filters()Calls the callback functions that have been added to a filter hook.
Source code
function atom_enclosure() { if ( post_password_required() ) { return; } foreach ( (array) get_post_custom() as $key => $val ) { if ( 'enclosure' === $key ) { foreach ( (array) $val as $enc ) { $enclosure = explode( "\n", $enc ); $url = ''; $type = ''; $length = 0; $mimes = get_allowed_mime_types(); // Parse URL. if ( isset( $enclosure[0] ) && is_string( $enclosure[0] ) ) { $url = trim( $enclosure[0] ); } // Parse length and type. for ( $i = 1; $i <= 2; $i++ ) { if ( isset( $enclosure[ $i ] ) ) { if ( is_numeric( $enclosure[ $i ] ) ) { $length = trim( $enclosure[ $i ] ); } elseif ( in_array( $enclosure[ $i ], $mimes, true ) ) { $type = trim( $enclosure[ $i ] ); } } } $html_link_tag = sprintf( "<link href=\"%s\" rel=\"enclosure\" length=\"%d\" type=\"%s\" />\n", esc_url( $url ), esc_attr( $length ), esc_attr( $type ) ); /** * Filters the atom enclosure HTML link tag for the current post. * * @since 2.2.0 * * @param string $html_link_tag The HTML link tag with a URI and other attributes. */ echo apply_filters( 'atom_enclosure', $html_link_tag ); } } }}Changelog
Introduced in 2.2.0. 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/feed.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.