wpmu_validate_blog_signup( string $blogname, string $blog_title, WP_User|string $user = '' ): array

Description

Compatibility

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

Parameters

$blognamestring

The site name provided by the user. Must be unique.

$blog_titlestring

The site title provided by the user.

$userWP_User|stringoptional

The user object to check against the new site name.
Default empty string.Default: ''

Return value

array

Array of domain, path, site name, site title, user and error messages.

• $domainstring

  Domain for the site.

• $pathstring

  Path for the site. Used in subdirectory installations.

• $blognamestring

  The unique site name (slug).

• $blog_titlestring

  Blog title.

• $userstring|WP_User

  By default, an empty string. A user object if provided.

• $errorsWP_Error

  WP_Error containing any errors found.

Performance profile

How much work a call to wpmu_validate_blog_signup() 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

Reaches the database via ->get_row().

Scaling

Constant

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

Instructions

101–204

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 240.

Plugin surface

3 hooks

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

Called by

2

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

What it touches

• optionnetwork optionget_site_option()called directly
• hookthird-party callbacksapply_filters()called directly
• sqldatabase query->get_row()called directly
• querycontent queryget_user_by()one call below wpmu_validate_blog_signup()

Further down the call graph this can also reach 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 · 598 distinct outcomes

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

This body has more branch combinations than are worth enumerating, so the table covers the outcomes found first rather than every one that exists.

Hooks and filters fired · 3

3 hooks fire while wpmu_validate_blog_signup() runs, in this order:

1. 1
   apply_filters( minimum_site_name_length )filterline 682 (+43 into the body)

   Filters the minimum site name length required when validating a site signup.

2. 2
   apply_filters( newblogname )filterline 709 (+70 into the body)

   Filters the new site name during registration.

3. 3
   apply_filters( wpmu_validate_blog_signup )filterline 785 (+146 into the body)

   Filters site details and error messages following registration.

Uses · 14

• get_network()Retrieves network data given a network ID or network object.
• get_site_option()Retrieve an option value for the current network based on name of option.
• add_site_option()Adds a new option for the current network.
• is_subdomain_install()Whether a subdomain configuration is enabled.
• get_subdirectory_reserved_names()Retrieves a list of reserved site on a sub-directory Multisite installation.
• __()Retrieves the translation of $text.
• apply_filters()Calls the callback functions that have been added to a filter hook.
• _n()Translates and retrieves the singular or plural form based on the supplied number.
• number_format_i18n()Converts float number to format based on the locale.
• wp_unslash()Removes slashes from a string or recursively removes slashes from strings within an array.
• domain_exists()Checks whether a site name is already taken.
• username_exists()Determines whether the given username exists.

Used by · 2

• validate_blog_form()Validates the new site sign-up.
• validate_blog_signup()Validates new site signup.

Source code

View on Trac ↗View on GitHub ↗

639function wpmu_validate_blog_signup( $blogname, $blog_title, $user = '' ) {640	global $wpdb, $domain;641 642	$current_network = get_network();643	$base            = $current_network->path;644 645	$blog_title = strip_tags( $blog_title );646 647	$errors        = new WP_Error();648	$illegal_names = get_site_option( 'illegal_names' );649 650	if ( ! is_array( $illegal_names ) ) {651		$illegal_names = array( 'www', 'web', 'root', 'admin', 'main', 'invite', 'administrator' );652		add_site_option( 'illegal_names', $illegal_names );653	}654 655	/*656	 * On sub dir installations, some names are so illegal, only a filter can657	 * spring them from jail.658	 */659	if ( ! is_subdomain_install() ) {660		$illegal_names = array_merge( $illegal_names, get_subdirectory_reserved_names() );661	}662 663	if ( empty( $blogname ) ) {664		$errors->add( 'blogname', __( 'Please enter a site name.' ) );665	}666 667	if ( preg_match( '/[^a-z0-9]+/', $blogname ) ) {668		$errors->add( 'blogname', __( 'Site names can only contain lowercase letters (a-z) and numbers.' ) );669	}670 671	if ( in_array( $blogname, $illegal_names, true ) ) {672		$errors->add( 'blogname', __( 'That name is not allowed.' ) );673	}674 675	/**676	 * Filters the minimum site name length required when validating a site signup.677	 *678	 * @since 4.8.0679	 *680	 * @param int $length The minimum site name length. Default 4.681	 */682	$minimum_site_name_length = apply_filters( 'minimum_site_name_length', 4 );683 684	if ( strlen( $blogname ) < $minimum_site_name_length ) {685		/* translators: %s: Minimum site name length. */686		$errors->add( 'blogname', sprintf( _n( 'Site name must be at least %s character.', 'Site name must be at least %s characters.', $minimum_site_name_length ), number_format_i18n( $minimum_site_name_length ) ) );687	}688 689	// Do not allow users to create a site that conflicts with a page on the main blog.690	if ( ! is_subdomain_install() && $wpdb->get_var( $wpdb->prepare( 'SELECT post_name FROM ' . $wpdb->get_blog_prefix( $current_network->site_id ) . "posts WHERE post_type = 'page' AND post_name = %s", $blogname ) ) ) {691		$errors->add( 'blogname', __( 'Sorry, you may not use that site name.' ) );692	}693 694	// All numeric?695	if ( preg_match( '/^[0-9]*$/', $blogname ) ) {696		$errors->add( 'blogname', __( 'Sorry, site names must have letters too!' ) );697	}698 699	/**700	 * Filters the new site name during registration.701	 *702	 * The name is the site's subdomain or the site's subdirectory703	 * path depending on the network settings.704	 *705	 * @since MU (3.0.0)706	 *707	 * @param string $blogname Site name.708	 */709	$blogname = apply_filters( 'newblogname', $blogname );710 711	$blog_title = wp_unslash( $blog_title );712 713	if ( empty( $blog_title ) ) {714		$errors->add( 'blog_title', __( 'Please enter a site title.' ) );715	}716 717	// Check if the domain/path has been used already.718	if ( is_subdomain_install() ) {

Changelog

Introduced in MU (3.0.0). 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

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