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function is not described

get_active_blog_for_user() WP 3.0.0

Get one of a user's active blogs

Returns the user's primary blog, if they have one and it is active. If it's inactive, function returns another active blog of the user. If none are found, the user is added as a Subscriber to the Dashboard Blog and that blog is returned.

No Hooks.

Return

WP_Site/null. The blog object

Usage

get_active_blog_for_user( $user_id );
$user_id(int) (required)
The unique ID of the user

Changelog

Since 3.0.0 Introduced.

Code of get active blog for user: wp-includes/ms-functions.php WP 5.2.2

<?php
function get_active_blog_for_user( $user_id ) {
	$blogs = get_blogs_of_user( $user_id );
	if ( empty( $blogs ) ) {
		return;
	}

	if ( ! is_multisite() ) {
		return $blogs[ get_current_blog_id() ];
	}

	$primary_blog = get_user_meta( $user_id, 'primary_blog', true );
	$first_blog   = current( $blogs );
	if ( false !== $primary_blog ) {
		if ( ! isset( $blogs[ $primary_blog ] ) ) {
			update_user_meta( $user_id, 'primary_blog', $first_blog->userblog_id );
			$primary = get_site( $first_blog->userblog_id );
		} else {
			$primary = get_site( $primary_blog );
		}
	} else {
		//TODO Review this call to add_user_to_blog too - to get here the user must have a role on this blog?
		$result = add_user_to_blog( $first_blog->userblog_id, $user_id, 'subscriber' );

		if ( ! is_wp_error( $result ) ) {
			update_user_meta( $user_id, 'primary_blog', $first_blog->userblog_id );
			$primary = $first_blog;
		}
	}

	if ( ( ! is_object( $primary ) ) || ( $primary->archived == 1 || $primary->spam == 1 || $primary->deleted == 1 ) ) {
		$blogs = get_blogs_of_user( $user_id, true ); // if a user's primary blog is shut down, check their other blogs.
		$ret   = false;
		if ( is_array( $blogs ) && count( $blogs ) > 0 ) {
			foreach ( (array) $blogs as $blog_id => $blog ) {
				if ( $blog->site_id != get_current_network_id() ) {
					continue;
				}
				$details = get_site( $blog_id );
				if ( is_object( $details ) && $details->archived == 0 && $details->spam == 0 && $details->deleted == 0 ) {
					$ret = $details;
					if ( get_user_meta( $user_id, 'primary_blog', true ) != $blog_id ) {
						update_user_meta( $user_id, 'primary_blog', $blog_id );
					}
					if ( ! get_user_meta( $user_id, 'source_domain', true ) ) {
						update_user_meta( $user_id, 'source_domain', $details->domain );
					}
					break;
				}
			}
		} else {
			return;
		}
		return $ret;
	} else {
		return $primary;
	}
}